JPH03183104A - Solenoid drive apparatus - Google Patents

Abstract

PURPOSE:To shorten the delay of the operating time of a solenoid by a method wherein a high voltage is applied to the solenoid at the beginning of driving the solenoid and, after that, a low voltage is applied. CONSTITUTION:A solenoid 1 is provided with the following: a voltage-application circuit 2 which supplies application voltages to two stages of different voltage values for drive use to the solenoid 1; and a timing circuit 3 which controls the voltage-application circuit 2 in terms of time and which applies application voltages of two stages to the solenoid 1 at the prescribed timing. A power supply +V for operation use is supplied to the solenoid 1 via either of transistors Q1, Q2 of the voltage-application circuit 2. A high voltage V2 1s applied to the solenoid 1 at the beginning of its drive; after that, a required voltage is applied to the solenoid 1. Thereby, at the beginning of operating the solenoid 1, its speed is increased; in a halfway part, it is suppressed that its movement speed is increased more than required; the operating time of the solenoid 1 is shortened and shock noise can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a solenoid drive device that is designed to muffle operating noise during operation.

[Prior Art] In recent years, as the office environment has improved, there has been a strong desire for lower noise from office equipment. There are various sources of noise generated from office equipment, such as printers, but solenoids are also a source, and the noise generated by these is caused by the fixed movable iron core being fixed to the yoke during the suction operation of the solenoid. This is the impact sound that occurs when the iron core collides with the iron core, and is one of the most unpleasant noises.

In order to suppress this impact noise, a stopper 12 is attached to the movable iron core 11 as shown in FIG. A shock member 13 is provided so that a gap α remains between the movable iron core 11 and the fixed iron core 14 even when the movable iron core 11 is attracted by the stopper 12 and the buffer member 13. A noise-muffling type solenoid is known, and such a structure prevents the movable iron core 11 and the fixed iron core 14 from directly colliding with each other during operation and suction, and can suppress impact noise to a low level.

Such a so-called noise-muffling type solenoid can certainly reduce the sound during operation compared to a normal solenoid, but when suctioning, the movable iron core 11 and the fixed iron core 14
It is necessary to configure the structure so that a gap α remains between the
To obtain the same suction force as a normal solenoid, it is necessary to apply a higher voltage, which increases the power supply capacity, which poses problems in terms of speed and cost.

In addition, the solenoid itself needs to be made large because it consumes a lot of power, which has been a major obstacle in design, especially in desktop equipment where miniaturization is strongly required.

Furthermore, if a silent type solenoid is used, the sound of the solenoid itself will be reduced, but when the solenoid is activated, the movable iron core 11 will be accelerated in the same way as a normal solenoid.
There is also a problem in that the sliding noise of a movable part such as a head lever of a tail recorder, which is driven by the movable iron core of the solenoid, cannot be reduced.

FIG. 7 is a characteristic diagram of the attraction force of the solenoid and its load for explaining the problems of the conventional solenoid drive device including this problem, and the figure shows the voltage v1. FIG. 4 is a diagram showing respective suction force curves when V2 is applied, and a load curve when the head lever of the tail recorder is used as the load as an example of the load.

In the load curve in the same figure, ■ is the point at which the paddle lever begins to move, ■ is the point at which the pinch roller contacts the cab stan and the spring for applying pinch pressure begins to move, and ■ is the point at which the solenoid operation is completed and the movable iron core is moved. It shows the load at the point where it is stopped in the suction state.

As you can see from the figure, the most severe condition for the solenoid is at point 0, but since this load condition exists, an applied voltage of V2 or higher is required to drive the rudder lever. , Since the load from point ■ to point 0 is light, when driven with applied voltage V2, the attraction force of the solenoid becomes excessive compared to the load in this section, so the movable iron core is accelerated more than necessary, and the movable iron core is Not only the impact noise when stopping, but also the sliding noise of movable parts such as the head lever when the movable iron core is in operation becomes louder.

[Problem to be Solved by the Invention 1] This invention was made to solve these problems, and the purpose of this invention is to reduce the operating noise of the solenoid itself and the movement associated with it, regardless of whether the solenoid is a normal type solenoid or a silent type solenoid. The purpose of the present invention is to provide a solenoid drive system that can suppress the sliding noise of parts.

[Means for Solving the Problems] The present invention provides a voltage application method in which a first applied voltage is applied to the solenoid at the initial stage of driving the solenoid, and a second applied voltage higher than the first applied voltage is applied after a predetermined period of time has elapsed. It is characterized by having the means.

Further, a first applied voltage is applied to the solenoid at the initial stage of its drive, a second applied voltage lower than the first applied voltage is applied after the first predetermined time has elapsed, and then the second applied voltage is applied again after the second predetermined time has elapsed. It is also characterized in that it includes a voltage application means for applying one applied voltage.

Furthermore, the above-mentioned solenoid drive devices are characterized in that the lower of the first applied voltage and the second applied voltage is the same as the solenoid holding voltage applied to the solenoid at the timing of completion of solenoid operation. It is said that

[Function] By configuring the solenoid drive device in this way, it is possible to apply an appropriate solenoid drive voltage to the solenoid according to the load.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. Fig. 1 shows a configuration circuit for explaining the solenoid drive device of this embodiment, in which 1 is a solenoid and 2
3 is a voltage application circuit that supplies two levels of applied voltage with different driving voltage values to the solenoid 1, and 3 temporally controls this voltage application circuit 2 to apply two levels of applied voltage to the solenoid at a predetermined timing. 1, and this timing circuit 3 controls the voltage application circuit 2 via base terminals bl and b2.

Solenoid 1 is connected to transistor Q1 of voltage application circuit 2. Q
2, and the circuit on the transistor Ql side is controlled by the timing circuit 3, and when the base terminal b1 reaches the "L" potential, a resistor is connected to the base of the transistor Q1. Base current flows through R1, turning transistor Q1 on, but since resistor R2 is inserted into the collector, a voltage Vl is applied to solenoid 1, which is obtained by subtracting the emitter-collector voltage and the voltage drop across resistor R2 from the power supply +V. It is now possible to do so.

On the other hand, in the circuit on the transistor Q2 side, when the base terminal b2 is controlled by the timing circuit 3 and reaches the "L" potential, a base current flows to the base of the transistor Q2 through the resistor R3, turning the transistor Q2 on, and the operating power supply +
A high voltage V2, which is almost close to the operating power supply +V excluding the emitter-collector voltage, is applied to the solenoid 1.

Each of the base terminals bl and b2 changes from "H" potential to "L" potential at the required timing by the timing circuit 3.
Alternatively, the solenoid 1 is driven from the "L" potential to the "H" potential to apply a necessary voltage to the solenoid 1.A specific example of the driving method of this embodiment is shown in FIGS. 2 and 3 (
aHb). FIG. 2 shows the load curve of the tape recorder paddle lever as an example of the load to be driven in this specific example, the suction curve of the solenoid 1 according to this embodiment for driving this load, and the suction curve of the solenoid 1 according to this embodiment for driving this load. The curve is generated by the timing circuit 3 in FIG.
) It is created at the timing shown in (b).

FIG. 3(a) shows the base terminals bl and b2 of the voltage application circuit 2.
FIG. 3(b) is a driving time chart of the voltage applied to the solenoid 1 at the timing shown in FIG. 3(a).

As you can see from the load curve in Figure 2, the load state ■ is lighter than the load state ■, and the load state ■ is lighter than the load state ■.
The gap between them is getting heavy.

In order to cope with such a load, the base terminal b1 is set to "L" from timing t1 to t2 as shown in FIG. 3(a).
potential, and at this timing t1 as shown in the same figure (b).
Therefore, voltage V1 is applied to solenoid 1 during t2, and from timing 2 onwards, voltage V2 is applied to solenoid 1 by setting base terminal b2 to "L" potential.

By applying such an operating voltage to the solenoid 1, the suction curve of the solenoid 1 has a characteristic as shown in FIG. According to this suction curve, the load condition ■ is better than the load condition ■
During the operating period up to this point, a low voltage V1 is applied to the solenoid 1, so the head lever is attracted and the pinch roller is moved at a slow speed until it touches the capstan. However, since the voltage V1 does not provide enough suction force to the solenoid to press the pinch roller against the capstan, the head lever temporarily stops at this position. Thereafter, at timing t2, the applied voltage is increased to V2, and the suction force is set to the suction force necessary for the load after the load state ①, and the pinch roller is pressed against the capstan via the spring. At this time, a high voltage ■2 is applied to the solenoid 1, but the moving stroke of the movable iron core is very short (usually 1 m+ or less) and -
Since the movement is from a stopped state, it reaches the final suction position in load state (3) without being accelerated.

By using such a solenoid drive device, it is possible to reduce the sliding noise during the suction process and the impact noise when stopping.

In the embodiment whose timing charts are shown in FIGS. 4(a) and 4(b), the voltage applied to the solenoid when the solenoid is in the load state (■) of the embodiment described above, that is, when the solenoid is in the holding state, is To prevent this, at timing t3 from the timing circuit 3, the base terminal bl is set to the "I,' potential again, and the base terminal b2 is set to the "H' potential, and the voltage is set to V.
It lowers it to l.

By adopting such a drive method, the power supplied to the solenoid during recording and playback can be reduced.
This can be done at the appropriate timing.

According to this driving method, since the holding voltage is 1, there is no need to provide a special circuit for applying the holding voltage.

The embodiment whose timing charts are shown in FIGS. 5(a) and 5(b) is for shortening the operating time of the solenoid 1, in which the base terminal b1 is set to the "T" potential for a predetermined period from timing t11 to t12. Also, set base terminal b2 to “L”
potential, apply a high voltage V2 to the solenoid 1 to accelerate the movable iron core, and from time t12 when it is accelerated to a predetermined value until timing t2, the base terminal b1 is set to "L" potential, and the base terminal b2 is set to the "L" potential. The voltage applied to the solenoid 1 is set to "H" potential and the voltage applied to the solenoid 1 is lowered to 1 to reduce the acceleration speed of the movable iron core.
At timing t2, the base terminal b1 is set to “H” potential again.
This is also an embodiment in which the base terminal b2 is set to the "L" potential and the voltage V2 is applied to the solenoid 1 to obtain the required suction force.

According to IPI, the speed of solenoid 1 is increased at the beginning of its operation, and during the middle of its operation, the movement speed is suppressed so that it does not increase more than necessary, thereby shortening the operation time of solenoid 1 and reducing impact noise. I can do it. Further, in this embodiment as well, the holding voltage may be set to vl as in the embodiment shown in FIG.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be modified and implemented without changing the gist.

For example, in the embodiment, a two-stage voltage was described as the voltage applied to the solenoid, but a multiple-stage voltage or one in which the voltage is continuously changed can be implemented as necessary.

Moreover, the applied voltage and timing can be combined in various ways depending on the load to be driven.

[Effects of the invention J According to this invention, the following effects can be expected.

a9 Even with a normal type solenoid, the impact noise and sliding noise associated with the operation of the movable iron core can be reduced.

b. Furthermore, if a high voltage is applied to the solenoid at the beginning of the solenoid's drive, and then a low voltage is applied thereafter, the delay in the activation time (rise) of the solenoid can be shortened.

C1 Furthermore, if the holding voltage of the solenoid is set to be the same as the lower applied voltage applied by the voltage applying means, there is no need to newly provide a circuit for applying the holding voltage, so that there is no increase in cost.

[Brief explanation of drawings]

Fig. 1 is a configuration circuit diagram of a solenoid drive circuit for explaining an embodiment of the present invention, and Fig. 2 is a load curve of a heel lever of a tape recorder used as a load for specifically explaining this embodiment. , a characteristic diagram of the suction curve of the solenoid that drives this load with the drive device of this embodiment, and FIGS. 3(a) and 3(b) respectively show the driving time of the base terminals b1 and b2 of the voltage application circuit 2 shown in FIG. 1. Chart and time chart of voltage applied to solenoid 1, Figure 4 (
a) and (b) are the drive time chart of the base terminals bl and b2 of the voltage application circuit 2 and the time chart of the voltage applied to the solenoid 1 shown in FIG. 1 for explaining the second embodiment, respectively; Figures (a) and (b) respectively show the voltage application circuit 2 shown in Figure 1 for explaining the third embodiment.
The driving time chart of the base terminals bl and b2 and the time chart of the voltage applied to the solenoid 1, Fig. 6 is a cross-sectional view of the solenoid to explain the conventional noise-reducing type solenoid, and Fig. 7 is the suction curve of the solenoid. It is a characteristic diagram explaining the relationship between and load. l... Solenoid 2... Voltage application circuit 3
...timing circuit

Claims (3)

[Claims] (1) A solenoid characterized in that it is equipped with a voltage application means that applies a first applied voltage to the solenoid at the initial stage of its operation, and after a predetermined period of time has passed, applies a second applied voltage that is higher than the first applied voltage. Drive device. (2) Apply a first applied voltage to the solenoid at the initial stage of its drive, apply a second applied voltage lower than the first applied voltage after the first predetermined time has elapsed, and further apply a second applied voltage after the second predetermined time has elapsed. A solenoid drive device comprising voltage application means for applying the first applied voltage again. (3) The lower of the first applied voltage and the second applied voltage is the same as the solenoid holding voltage applied to the solenoid at the timing of completion of solenoid operation. 2. The solenoid drive device according to 2.