JPS6043646B2 - electromagnetic solenoid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electromagnetic solenoid suitable for driving a type cup or the like of a printing device such as an electronic typewriter.

Conventional Structure and Problems When moving a rotating object in the direction of its rotational axis, a mechanism that combines an electromagnetic solenoid and a link has conventionally been used.

FIG. 1 shows a printing section of a printing device, which has a mechanism for moving a rotating type cup up and down using an electromagnetic solenoid. In the figure, 10 is a platen holding printing paper 11, 12 is a type cup, and on the outside of the tip of the spoke, type letters 14a and 14b are arranged in two rows, upper and lower. A printing hammer 16 is arranged on the back side of the printing type 14a, 14b, and when a signal is input, the printing hammer 16 moves the printing type 14a or 14b onto the printing paper 1.
Hit 1. Type 14a or 14b and printing paper 1
There is an ink ribbon 17 between the two, and printing is performed. The type cup 12 is fixed to a type holding member 18, and since the convex portion 19 of the type holding member 18 fits into a notch 15 formed in the bottom of the type cup 12, rotational movement can be transmitted. can. The type holding member 18 and the type cup 12 are supported on a rotating shaft 19a of a motor 19 so as to be rotatable and movable up and down. A rotation transmission member 20 is fixed to the rotation shaft 19a of the motor 19,
The pin 21 fixed to the rotation transmitting member 20 and the protrusion 22 of the type holding member 18 are connected to the rotation shaft 19 of the motor 19.
Because they are interlocked so that they can be moved in the longitudinal direction of a,
The rotation of the motor 19 is transmitted to the type cup 12 via the type holding member 18. Reference numeral 23 designates an electromagnetic solenoid, and its movable core 24 is connected to one end of a shift lever 26 rotatably attached to a fixed portion by a pin 25.

The other end of the shift lever 26 is connected to the groove 1 of the type holding member 18.
A roller 27 that fits into 8a is rotatably attached. The vertical movement of the movable core 24 causes the type cup 12 to move up and down via the type holding member 18. The electromagnetic solenoid 23 includes a yoke 28 that forms a magnetic path together with the movable core 24, a coil 29 that generates magnetic flux in the magnetic path to attract the movable core 24 to the yoke 28, and a guide vibe 30 that guides the movement of the movable core 24. A coil spring 31 is attached to the movable core 24 to urge the movable core 24 upwardly. The conventional configuration described above requires a complicated mechanism to move the rotating type cup up and down, so it is not suitable for downsizing the device, and has low reliability due to high frictional force and rattling due to wear. Furthermore, in order to hold the movable iron core in an adsorbed state, electricity must be constantly supplied, resulting in increased power consumption and problems such as temperature rise due to heat generation.

Purpose of the Invention The purpose of the present invention is to provide an electromagnetic solenoid that can directly move a rotating object, which is a driven body, in the axial direction, and that can operate with low friction and inertial loads and with low drive energy. It is about providing.

Structure of the Invention The electromagnetic solenoid of the present invention includes a rotor including a magnetic material rotatably disposed, and a first position rotatable coaxially with the rotor and spaced apart from the rotor by a required distance. and a second position in contact with or close to the rotor; A yoke made of a magnetic material disposed in close proximity to the rotor and the movable core, respectively, generates magnetic flux in the magnetic circuit when energized, and generates a magnetic attraction force between at least the rotor and the movable core. magnetic flux generating means including a coil for moving the movable iron core from the first position to the second position; and generating a magnetic flux between the movable iron core brought to the second position and the rotor. a permanent magnet that holds the movable iron core at the second position, the movable iron core is capable of rotating a driven object (such as a type cup in a printing device), and the longitudinal axis of the rotation axis is It can be supported movably in any direction.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a side view of essential parts showing an embodiment in which the electromagnetic solenoid according to the present invention is used in a printing device.

In the figure, 10 is a platen that holds printing paper 41. 42 is a type force 7, which is generated by applying a plurality of spokes 44 vertically at predetermined intervals from near the outer periphery of the disk portion 43.
is extended, and letters 45a and 45b are formed in two upper and lower stages at the outer tip of each spoke 44.

A gear 46 is formed on the outer periphery of the disk portion 43 of the type cup 42, and a gear 48 is fixed to the rotating shaft of a motor 47.
They are interlocked. Further, the disk portion 43 is provided with holes or notches 43a, and these holes or notches 43a
, there is a convex portion 5 such as a pin implanted in the type mounting member 49.
0 is inserted, so that the type mounting member 49 and the type cup 42 can rotate and move up and down as one unit.
An operating body 51a of a printing hammer 51 disposed on a fixed base 60 is located on the back side of the type 45a (or 45b).

When a signal is applied to the printing hammer 51, the actuating body 51a
is made to protrude to the right in FIG.
b) Push toward the printing paper 41. Then spoke 44
has an appropriate elastic force, so that the printed characters 45a (or 45b) are pressed against the printing paper 41. An ink ribbon 52 is placed between the type 45a (or 45b) and the printing paper 41.
Since this is provided, printing is performed. 47 is a motor for controlling the rotational position of the type cup 42, and the rotational position of this motor is controlled by a control circuit (not shown). A gear 48 attached to the motor 47 connects the type cup 4
2 shifts in the vertical direction, the gear 46 of the type cup 42
It has a thickness that maintains interlocking. Reference numeral 53 designates an electromagnetic solenoid for vertically moving the type cup 42, and when a shift signal is input, this solenoid attracts and moves the armature 54 having the type type mounting member 49 attached to its lower end upwardly by electromagnetic force.

As a result, as shown in FIG. 2, the type cup 42 is lowered to a position (hereinafter referred to as the first
position) to a position where the type cup 42 is raised so that the lower type type 45a faces the tip of the actuating body 51a of the printing hammer 51 (hereinafter referred to as the second position). Ru. Although the details will be described later, in this embodiment, after the armature 54 has been moved by suction, the armature 5 is configured to maintain the type cup 42 at the second position even if the supply of the shift signal to the electromagnetic solenoid 53 is cut off.
4 in the upward shift position. Further, when a reset signal is supplied to the electromagnetic solenoid 53, the armature 54 is released from being held at the shift position and returns downward, and accordingly, the type cup 42 also returns from the second position to the first position. It's getting old. FIG. 3 is a sectional view of an embodiment of the present invention that is effective when used as the electromagnetic solenoid 53. A shaft 61 is fixed to the center of a fixed base 60, and a cylindrical rotor is attached to the shaft 61. 62 and armature 54 which is a movable iron core.
are supported in a vertical positional relationship.

The rotor 62 is made of a magnetic material, and a slip bearing 63 is press-fitted into the center thereof. Therefore, rotor 6
2 can freely rotate on a shaft 61. Further, although the rotor 62 can also move in the axial direction, normally the flange portion 61a provided on the shaft 61 is moved by its own weight.
It's parked on top. The armature 54 is also made of magnetic material and has slide bearings 55, 5 in its center.
6 is press-fitted. Therefore, the armature 54 is rotatable on the shaft 61 and movable in the longitudinal direction of the shaft. A coiled spring 64 is provided between the armature 54 and the collar portion 61a of the shaft 61, and urges the armature 54 to move downward so as to bring the type cup 42 to the first position. The armature 54 is stopped at a position where its lower end contacts an E-ring 65 attached to the shaft 61 by the biasing force of a coiled spring 64. In this position, the slider washer 66 is sandwiched between the underbelly bearing 56 and the E-ring 65, so the rotational resistance of the armature 54 is very small.

The upper portion 54a of the armature 54 is tapered and the upper portion 54a of the armature 54 is tapered.
The same tapered recess 62a as the upper part of the armature 54 is formed in the lower part of the rotor 62 facing the .

Yokes 68 and 68 are made of a magnetic material and have substantially inversely convex and concave cross sections, respectively, and are coupled and arranged so as to surround the coil 69.

The yoke 67 has a through hole 67a in its center that is large enough to accommodate the rotor 62 in a non-contact manner and to allow the upper part 54a of the armature 54 to enter and exit the recess 62a of the rotor 62 from below. The yoke 67
, 68, the inner circumferential portions 67a, 68a of the through holes 68 are provided with appropriate gaps 70,
He holds 71 and faces the opponent. On the other hand, a cylindrical (or ring-shaped) permanent magnet 72 is fixed to the lower surface portion 67c of the yoke 67.

This permanent magnet 72 is magnetized in the thickness direction, and a ring-shaped core 73 made of a magnetic material is fixed to the lower surface. The core 73 has an inner circumferential surface 73a that is connected to the armature 5.
It faces the outer circumferential surface of No. 4 with a required gap 74 in between. FIGS. 4 and 5 schematically show the magnetic flux generated inside the shift solenoid 53. FIG. 4 shows the armature 54 in the lowered return position, and FIG. 54 is in the upward shift position.

In FIG. 4, the solid line represents the magnetic flux generated by the permanent magnet 72, and the broken line and the dashed line represent the magnetic flux generated by the coil 69 when a shift signal is input.

As shown in FIG. 4, when the armature 54 is in the return position, the magnetomotive force of the permanent magnet 72 applies magnetic flux to the magnetic path from the core 73 to the gap 74 to the armature 54 to the gap 71 to the yoke 62 to the yoke 67. generate. Gap 74 and Gap 7
Since the direction of the magnetic flux passing through 1 is in the radial direction of the armature 54, no force is generated to move the armature 54 in the axial longitudinal direction. In addition, depending on the magnetic flux, a. A force is generated that pulls the armature 54 in the radial direction, but since the gaps 71 and 74 are axially symmetrical, they cancel each other out, and the armature 54 is not subjected to any force in the radial direction. Therefore, the sliding bearings 55 and 56 of the armature 54 do not receive lateral pressure! The rotational resistance is very small. In the state shown in FIG. 4, when a shift signal is input to the coil 69, a magnetic flux is generated in the magnetic path from the yoke 67 to the yoke 68 to the gap 71 to the armature 54.

When the distance between the armature 54 and the rotor 62 is large, most of the magnetic flux emitted from the armature 54 is transferred to the rotor 62.
It does not pass through the flange portion 67c of the lower part of the yoke 67. When the armature 54 begins to move upward as the coil 69 is energized and the distance from the rotor 62 becomes smaller, the magnetic flux emitted from the armature 54 flows from the rotor 62 to the gap as shown by the dashed line in FIG. 70 and enters the yoke 67. Armature 54 and yoke flange portion 67
d1 or the magnetic flux passing between the armature 54 and the rotor 62 generates a force that moves the armature 54 in the axial direction. In this case as well, the forces that pull the armature 54 in the radial direction cancel each other out, so no side pressure is generated, and the armature 54 can be smoothly moved and rotated in the axial direction.
Here, when the armature 54 is attracted to the rotor 62,
The magnetomotive force of the permanent magnet 72 generates a magnetic flux as shown by the solid line in FIG.

Permanent magnet 72 - core 73 - gap 74 - armature 54
- ~ Rotor 62 ~ Gap 70 ~ Yoke 67 ~ Permanent magnet 72
The armature 54 is magnetically attracted to the rotor 62 due to the magnetic flux passing through the magnetic path. Magnetic flux is also generated in another magnetic path from permanent magnet 72 to core 73 to gap 74 to armature 54 to gap 71 to yoke 68 to yoke 67 to permanent magnet 72, but no force is generated in armature 54.
Further, since this magnetic path has a larger magnetic resistance hole than the aforementioned magnetic path, most of the magnetomotive force of the permanent magnet 72 acts to attract the armature 54 to the rotor 62. Therefore, even if the coil 69 is de-energized, the armature 54 remains moved upward, and the type cup 42 remains in the second position. When a return signal (a signal flowing in the opposite direction to the shift signal) is applied to the coil 69 in order to return the armature 54 to the return position, a magnetic flux as shown by the broken line in FIG. 5 is generated.

Of the magnetic flux generated by the permanent magnet 72, the magnetic flux passing through the armature 54 to the rotor 62 is canceled out by this magnetic flux, and a portion of the magnetic flux is detoured from the armature 54 to the yoke flange portion 67d as shown by the dashed line. As a result, the armature 54 is no longer subjected to the attraction force in the longitudinal direction of the shaft due to the magnetic force of the permanent magnet 72, so it moves downward due to its own weight and the action of the coiled spring 64, returns to the return position, and stops. By energizing the coil 69 as described above, the armature 54 is attracted to the rotor 62 by electromagnetic force, and after being attracted, the attracted state is maintained by the magnetomotive force of the permanent magnet 72.

Then, when the coil 69 is energized in the opposite direction to that during shifting, the suction is released and the armature 54 returns to the return position. Therefore, by supplying a shift signal and a return signal to the coil 69, the type cup 42 is moved from the first position to the second position (selecting the type 45b) or from the second position to the first position. (select type 45a). As described above, according to the embodiment of the present invention shown in FIGS. 3 to 5, the armature connected to the type mounting member for attaching the type cup is moved up and down directly and without contact by magnetic force. becomes possible.

Therefore, the number of operating members is reduced, reliability is improved, and the device can be made smaller. Moreover, since the rotational resistance when rotating the type cup is small, effects such as a reduction in the load on the motor can also be obtained. Furthermore, no electrical energy is required to hold the type cup in the shift position, and the coil only needs to be energized when shifting and resetting, which is advantageous for power saving. Moreover, since there is a bypass in the magnetic path at the time of reset, it also has the effect that the excitation force that cancels the magnetic flux caused by the permanent magnet can be small.

Next, other embodiments of the present invention are shown in FIGS. 6 to 8 of the drawings.
This will be explained with reference to the figures.

In FIG. 6, a shaft 102 made of a magnetic material is fixed to the center of a fixed base 60, and a cylindrical rotor 103 and an armature 105 are supported on this shaft as in the previous embodiment. . The rotor 103 is made of a magnetic material, and an oil-impregnated belly bearing 104 made of iron-based sintered metal is press-fitted into the center. The rotor 103 is the shaft 1
Although it is rotatably supported on the shaft 102 and movable in the longitudinal direction of the shaft, it is normally stopped on the collar portion 102a of the shaft 102 due to its own weight. The armature 105 is also made of a magnetic material, and slide bearings 106 and 107 made of a non-magnetic material are press-fitted into the center thereof. The armature 105 is capable of rotation and vertical movement on the shaft 102. A cylindrical permanent magnet 108 magnetized in the radial direction is provided inside the center of the armature 105.
A type mounting member 49 is fixed to the lower end of the . The upper end 105a of the armature 105 is tapered, and the armature 10 is formed at the lower part of the rotor 103.
A tapered recess 103a is formed into which the upper end 105a of 5 can be inserted. The yokes 110 and 111 are made of a magnetic material and are arranged to surround a shift coil 113 and a reset coil 114 wound around a bobbin 112. The inner peripheral portions 110a and 111a of the yoke face the outer peripheral surfaces of the armature 105 and the rotor 103, respectively, with predetermined gaps 115 and 116 in between. An E-ring 117 that serves as a stopper for the armature 105 and a cap 118 made of a magnetic material are attached to the lower end of the shaft 102. The armature 105 has a coiled spring 119 at its lower end, and an E-ring 117 by the action of its own weight and magnetic force (described later).
It is stopped at a position (return position) where it comes into contact with the slider washer 120 sandwiched between the slider washer 120. Figure 7 shows armature 1
This figure shows the flow of magnetic flux generated by the permanent magnet 108 when the magnet 05 is in the return position.

A part of the magnetic flux generated by the permanent magnet 108 passes through the magnetic path from the permanent magnet 108 to the armature 105 to the cap 118 to the shaft 102 to the permanent magnet 108, as shown by the solid line in the figure, so the armature 105 applies downward force. receive.
Furthermore, as shown by the dashed line in the figure, some magnetic flux leaks to other magnetic paths. By adjusting the shape of the cap 118 and the distance from the armature 105, the force for holding the armature 105 in the return position can be adjusted. Here, when the solenoid 113 is energized when the armature 105 is at the lowest return position, magnetic flux is generated in the magnetic path from the yoke 110 to the armature 105 to the rotor 103 to the yoke 111, and the armature 105 receives an upward force. and is attracted to the rotor 103 by electromagnetic force.

FIG. 8 schematically shows the magnetic flux in the attracted state.

In the figure, the armature 105 is attracted to the rotor 103 by the magnetic flux generated by the permanent magnet 108 as shown by the solid line. l When the reset coil 114 is energized, a magnetic flux shown by a broken line in the figure is generated, canceling the magnetic flux generated by the permanent magnet 108, and a part of the magnetic flux passes through the bypass as shown by a dashed line.

Therefore, the attraction force between the rotor 103 and the armature 105 disappears, and the armature 105 moves downward by its own weight and the action of the coiled spring 119 to return to its original state. As described above, according to the embodiments shown in FIGS. 6 to 8, the shift mechanism can be made smaller and the reliability is improved, as in the previous embodiments.

Also, the load on the motor that rotates the type cup is reduced,
No electrical energy is required to maintain the shifted state. Furthermore, since there is a bypass in the magnetic path when resetting the shift, the excitation force required for resetting is small, and since there are dedicated coils for each shift and reset, it can be used with a single power supply voltage. have

In this embodiment, an iron-based sintered material is used for the rotor bearing, but a thin bearing material such as resin may also be used.

Effects of the Invention As is clear from the above description, the electromagnetic solenoid of the present invention has a structure that rotatably supports a driven body and moves and displaces the driven body directly in the longitudinal direction of the rotation axis. Therefore, the driven body can be reliably driven with a relatively simple and compact structure.

In addition, since the present invention can rotatably support a driven body without increasing rotational resistance or inertial load, when rotating a driven body with a motor, a small and inexpensive motor with low output can be used. It has the advantage that it can be used.
Furthermore, as shown in the above embodiment, the driven body is
If the magnetic force of a permanent magnet is used to hold the moved position, no special electrical energy is required to hold it, which is advantageous in terms of reducing power consumption. It has various excellent features, such as being able to drive with very little energy as it only requires changing the direction of the current flowing through the coil or energizing the reset coil.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view showing a conventional electromagnetic solenoid and its application example, Fig. 2 is a partially cutaway side view showing an application example of the present invention, and Fig. 3 is an embodiment of the electromagnetic solenoid of the present invention. , FIGS. 4 and 5 are enlarged side sectional views of essential parts of the same embodiment in various states, and FIG. 6 is a side sectional view of other embodiments of the electromagnetic solenoid of the present invention, and FIGS. FIG. 8 is an enlarged side sectional view of the main part in each state of the embodiment. 53... Electromagnetic solenoid, 54,105...
... Armature, 60 ... Fixed base, 61,1
02... Shaft, 62, 103... Rotor, 64, 119... Coiled spring, 67
,68,110,111...York,69,1
13,114... Coil, 72,108...
・Permanent magnet, 73...core.

Claims (1)

[Scope of Claims] 1. A rotor made of a magnetic material arranged to be rotatable, and a first position that is rotatable coaxially with the rotor and is spaced apart from the rotor by a required distance, and that contacts or contacts the rotor. a movable core that is movable between adjacent second positions, and at least a portion of which is adjacent to each of the rotor and the movable core so as to form a magnetic circuit including the rotor and the movable core; a yoke made of a magnetic material arranged to magnetic flux generating means including a coil that generates a magnetic attraction force between the rotor and the movable iron core to move the movable iron core from the first position to the second position; An electromagnetic solenoid comprising a permanent magnet that generates magnetic flux between the movable core and the rotor to hold the movable core at the second position. 2 The rotor is composed of a magnetic material with a cylindrical outer circumference,
The electromagnetic solenoid according to claim 1, characterized in that the electromagnetic solenoid has a structure in which the solenoid is accommodated in a non-contact state in a through hole provided in the center of the yoke. 3 The magnetic flux generating means has one coil, and moves the movable iron core from the first position to the second position according to the direction of the current flowing through the coil.
3. The electromagnetic solenoid according to claim 1, wherein the electromagnetic solenoid is configured to perform a shift operation to move the solenoid to the second position and a return operation to return from the second position to the first position. 4. The magnetic flux generating means has first and second coils that generate magnetic flux in opposite directions when energized, the first coil is energized to perform a shift operation, and the second coil is energized to perform a shift operation. The electromagnetic solenoid according to claim 1 or 2, wherein the electromagnetic solenoid is configured to perform a return operation. 5 The permanent magnet is magnetized in the thickness direction, one magnetized end surface is joined to the yoke, and the other magnetized end surface is
3. The electromagnetic solenoid according to claim 1 or 2, wherein a ring-shaped core whose inner peripheral surface faces the outer periphery of the movable iron core with a required gap is joined. 6 The rotor and the movable core are arranged on a shaft made of a magnetic material, and a cylindrical permanent magnet magnetized in the radial direction is used, and the permanent magnet is moved integrally with the movable core. 3. The electromagnetic solenoid according to claim 1, wherein the electromagnetic solenoid is disposed on the outer periphery of the shaft. 7. Claims characterized in that the rotor has a tapered concave portion in the portion facing the movable core, and the movable core has a tapered portion in the portion facing the rotor that fits into the concave portion. The electromagnetic solenoid according to item 1 or 2. 8. The electromagnetic solenoid according to claim 1 or 2, characterized in that a bypass is provided near the magnetic path formed by the rotor and the movable iron core for bypassing the magnetic flux passing through the magnetic path. .