JPH05199733A - Intermittent driving gear - Google Patents

Abstract

PURPOSE:To provide a small-sized and low-power-consumption intermittent driving gear by driving it accurately by the control of an open loop, and enabling it to stop the power supply to an actuator by fixing the slider with a stopping mechanism after positioning, concerning a low-power-consumption and ultrasmall intermittent driving gear which performs the intermittent driving of a micromachine. CONSTITUTION:Claw teeth 3 are made at the stator 2 of an intermittent driving gear 1, and a slider 4 is equipped with a claw 5, which engages with the claw teeth 3, and it shifts by one tooth of the claw teeth 3 being one intermittent driving unit while measuring the condition of the claw teeth 3, using a position measuring mechanism, and even if the power supply to a linear actuator 8 is stopped, it is fixed by the engagement between the claw tooth 3 and the claw 5 and the tension of a bias spring 10. At recovery to the initial position, the claw 5 is retained in the position of being jumped up at the final end 11, and the resetting is performed at the initial position with a recovery mechanism 14, so an intermittent driving gear, which performs the highly accurate positioning with low power consumption, can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low power consumption ultra-small intermittent drive device for intermittently driving a micromachine.

[0002]

2. Description of the Related Art In recent years, interest in micromachines has increased, and various actuators have been devised. The micromachine is required to be small, and when it is applied as a microrobot, it is absolutely necessary to operate with low power consumption.

In a relatively large machine, a linear drive for intermittent drive is realized in combination with a rotary actuator such as a stepping motor. However, in the case of a linear actuator when mounted on a micromachine,
It is difficult to maintain the self-position when intermittent driving is used, and it is often necessary to always energize.

Examples of conventional linear actuators include linear DC motors, linear induction motors, linear pulse motors, voice coil motors, and electrostatic linear motors. These actuators are described in detail in Practical Encyclopedia, Shota Miyairi, edited by Fuji Techno System (1988) P212-234.

FIG. 3 shows a conventional linear DC motor,
15A is a front view and FIG. 18B is a side view.
Is a coil, 16 is a magnet, and 17 is a yoke.

In the figure, when the coil 15 is energized,
Current I flowing through coil 15 in a magnetic field of magnetic flux density B (T)
Due to (A), the coil 15 receives the force F (N).

F = I · B (1) If the magnet 16 and the yoke 17 are used as a stator and the coil 15 is a slider 18, a linear actuator can be constructed by controlling the current flowing through the coil 15.

A linear scale 19 is used to control the position of the slider 18, and the resolution of the linear scale 19 is controlled to about ± 1 pulse. That is, when the movement target value is given, a current is passed through the coil 15 so that the measured value of the linear scale 19 and the movement target value match, and the vehicle moves to the target position while performing appropriate acceleration / deceleration. Further, since the slider 18 is displaced due to the disturbance and the measurement value of the linear scale 19 changes, the direction of the current flowing through the coil 15,
The size of the linear scale 19 is controlled so that the measured value of the linear scale 19 matches the movement target value again.

The voice coil motor has the same principle as that of the linear DC motor and is different only in form. That is, as seen in a speaker, the coil 15 has a cylindrical shape, and the magnet 16 and the yoke 17 are configured so as to enclose the coil 15.

FIGS. 4A to 4E show a conventional linear pulse motor, which is called a Sawyer type motor. Reference numeral 20 denotes a stator having teeth 21 with a pitch P formed therein. Two electromagnets 22 connected by the magnet 16 are installed on the slider 18 at intervals of 1.25P.

The electromagnet 22 has two poles 23 at an interval of 1.5P, and the winding directions of the coil 15 are opposite to each other. There are a total of four poles 23 on the slider 18, and when the coils 15a and 15b are energized alternately and while reversing their polarities ((e) in the same figure), the slider 18 becomes 0.
The movement is performed in steps of 25P ((a) in the same figure).
(D)). In this conventional example, the slider 18 is stabilized by the magnetic force between the teeth 21 carved on the stator 20 and the poles 23. Therefore, when the force acting from the outside is small, feedback control is not performed and use in an open loop is performed. Is also possible.

[0012]

However, the above-mentioned conventional configuration has the following problems. 1) A linear DC motor requires a position detector such as a linear scale or an encoder, and moreover, in order to fix the position detector at an arbitrary position, it is always necessary to supply electric power to the motor by feedback control. 2) In the linear pulse motor, the position is stabilized by the attraction force of the teeth engraved on the magnet and the stator.
When the power supply to the coil is stopped, the slider easily moves, so that power supply is necessary even in the stopped state. 3) In the linear pulse motor, further, the positioning accuracy is lowered due to the influence of tooth pitch deviation between magnetic poles, the difference in magnetic path length, the nonuniformity of the air gap length, the residual magnetism of the material, and the feeding speed is too fast. May cause step out, and it may not be possible to use it in an open loop.

The present invention solves the above-mentioned problems of the prior art. The position measuring mechanism measures the position and the stop mechanism fixes the position to the moving position. Guarantee the positioning accuracy of
An object of the present invention is to provide an intermittent driving device capable of eliminating power consumption other than during driving by performing intermittent driving.

[0014]

In order to achieve this object, an intermittent driving device of the present invention has a position measuring mechanism and a stopping mechanism on a slider of a linear driving device which receives a force in one direction by a bias spring. , Has an intermittent release mechanism that holds the stopper mechanism when the slider is driven to the final end.

Further, the stopping mechanism is composed of one or more claw tooth racks, a claw having a mirror surface that meshes with the rack, and a spring or a magnet for meshing the claws with the claw tooth rack.

The position measuring mechanism is composed of a light projector, two or more light receivers, and a mirror surface provided on the claw of the stopping mechanism.

Further, it has an intermittent releasing mechanism for holding the claw teeth of the stop mechanism when the slider is driven to the final end, and a returning mechanism for returning the claw teeth of the stop mechanism when the slider is returned to the initial position.

[0018]

According to the present invention, with this structure, the slider of the linear driving device is fed by one intermittent driving unit by one pawl tooth pitch, and the pawl rack is quickly engaged with the pawl tooth rack by the spring or magnet of the stop mechanism. As a result, the position is fixed by the reaction force between the claw and the bias spring that engage with each other when the energization is stopped.

The movement of one intermittent drive unit is measured by the position detection mechanism. That is, when the light emitted from the projector is reflected by the mirror surface provided on the claw teeth and the reflected light is detected by the light receiver, by providing two or more light receivers, the claws will be Light is received when the pawl is passed over the tooth rack and the pawl is held by the intermittent release mechanism.

When it is detected by the position detection mechanism that one tooth of the claw tooth rack has been passed over, the power supply to the drive mechanism can be stopped and the power consumption can be suppressed.

To return the slider to the initial position,
The intermittent release mechanism holds the stop mechanism at the final end of the linear drive, and the position detection mechanism detects the holding of the pawl teeth, and then returns the slider of the linear drive device to the initial position.

When the slider has returned to the initial position, the pawl is engaged with the pawl tooth rack by the function of returning the stop mechanism held by the intermittent release mechanism, and the stop mechanism is operated again to perform continuous intermittent drive.

Since the slider can be driven for each intermittent drive unit of the stopping mechanism and the electric power can be completely cut off at the time of stop, as a result, the power consumption becomes low, and moreover, the position measuring mechanism surely operates the pawl tooth rack. Since the stepping drive is performed pitch by pitch, position control is performed accurately by open loop drive.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first intermittent drive device according to the present invention.
FIG. 7A shows a state of an intermediate point of intermittent driving, FIG. 7B shows a state where the pawl is held at the final end, and FIG. 7C shows a state where it is returned to the initial position. Shows.

2A and 2B show a position measuring mechanism of an intermittent drive device according to the present invention. FIG. 2A shows a state in which a claw and a claw tooth are engaged with each other, and FIG. 2B shows a claw to a claw tooth. The state where the claw is held up at the final end is shown in the state (c) of FIG.

In the state shown in FIG. 1 (a), the stator 2 of the intermittent drive unit 1 has pawl teeth 3 formed thereon, and the pawls 5 of the slider 4 are rotated about the pins 6 on the slider 4 so as to mesh with the teeth. It is movably mounted and is pressed against the pawl teeth 3 of the stator 2 by a spring 7.

A mirror surface 24 is formed on a part of the claw 5, and the slider 4 has a light projector 25 and light receivers 27, 28, and 2.
9 is provided.

In the state where the claw 5 shown in FIG. 2 (a) is pressed against the claw teeth 3, the light 26 emitted from the projector 25 is a mirror surface 24.
And is detected by the light receiver 27.

The slider 4 is moved in the moving direction 9 by supplying electric power to the linear actuator 8. When the slider 4 moves, the pawl 5 slides along the slope of one tooth of the pawl tooth 3 and meshes with the next tooth.

The light 26 is detected by the light receiver 28 when it goes up the slope of the claw tooth 3 shown in FIG. 2B, and is again detected by the light receiver 27 when it is engaged with the next tooth. Here, when the power supply to the linear actuator 8 is stopped, the bias spring 10 tries to pull it back, the claw teeth 3 and the claw 5 mesh with each other, and the slider 4 is fixed. The bias spring 10 is composed of a coil spring, a mainspring or the like in an intermittent drive device having a small movement stroke, and a constant tension spring is used when the movement stroke is large.

In FIG. 1B, when the slider 4 reaches the final end 11, the holding mechanism 12 having a tooth height higher than that of the claw teeth 3 lifts the claw 5 and the magnet 13 holds the claw 5. Since the attraction force of the magnet 13 is larger than the pressing force of the spring 7, it does not come off naturally. At this time, as shown in FIG. 2C, the light 26 is detected by the light receiver 29, and it is confirmed that it is securely held.

While the claw 5 is attracted to the magnet 13,
When the amount of power supplied to the linear actuator 8 is temporarily reduced, the slider 4 is pulled by the bias spring 10 and returns to the initial position in the opposite direction to the moving direction 9.

FIG. 1C shows the initial state of the intermittent driving device. When the slider 4 returns from the state of FIG. 1B, the return mechanism 14 separates between the claw 5 and the magnet 13 and the claw 5 moves. Are again engaged with the claw teeth 3. The light 26 is again a light receiver 27
It is confirmed that the initial state has been restored.

If it is moved again from the initial position, continuous intermittent driving becomes possible. The linear actuator 8 is
It may be electrostatic or electromagnetic, and it may be a DC motor, a voice coil motor or the like that moves continuously or a pulse motor that moves intermittently. The pitch of the intermittent drive is the pitch of the claw teeth 3 regardless of which actuator is used.

When the light 26 is detected by the light receiver 27, the driving power may be turned off. Since the movement of one intermittent drive pitch is completed when the light receiver 27 receives the light after it is detected by the light receiver 28, if the energization is stopped at this timing, the reliable movement is performed.

If the pitch of the claw teeth 3 is set to a desired movement pitch, it is possible to perform extremely precise positioning by controlling the open loop.

[0038]

INDUSTRIAL APPLICABILITY As described above, the intermittent drive device of the present invention has the following advantages. 1) The positioning of the linear actuator is determined by the pitch of the claw teeth, and the pitch of the claw teeth is manufactured to have a required fine pitch, so that the linear actuator can be accurately moved only by controlling the open loop. 2) Since it can be confirmed that the pawl surely crosses the pawl tooth and drives the slider by one intermittent drive unit, an error due to step-out may occur even when the linear actuator for driving is a stepping motor. There is no. 3) Stopping at the position where it is positioned is performed by the engagement between the claw teeth and the claw and the tension by the bias spring, so that the slider will not be displaced even if there is a disturbance. 4) When the slider is stopped, power supply can be completely stopped, so that low power consumption is achieved. 5) Since it is not necessary to perform feedback control, the control circuit can be simplified and the device can be downsized, so that a micromachine can be realized. 6) Stopping the slider, releasing the stop mechanism, and returning the stop mechanism are easily and automatically performed. 7) Since the state of the pawl at the time of stopping the slider, releasing the stopping mechanism, and returning the stopping mechanism can be confirmed, trouble can be prevented in advance.

As described above, the intermittent driving device according to the present invention can be widely applied as a low power consumption, small-sized driving device which performs accurate intermittent driving with simple control.

[Brief description of drawings]

FIG. 1 is a side view of an intermittent drive device according to an embodiment of the present invention.

FIG. 2 is a side view of a position measuring mechanism which is a main part of the intermittent driving device.

FIG. 3 is a front and side view of a conventional linear DC motor.

FIG. 4 is a conceptual diagram of a conventional linear pulse motor.

[Explanation of symbols]

 1 Intermittent Drive Device 2 Stator 3 Claw Teeth 4 Slider 5 Claw 6 Pin 7 Spring 8 Linear Actuator 9 Moving Direction 10 Bias Spring 11 Final End 12 Holding Mechanism 13 Magnet 14 Return Mechanism 15 Coil 16 Magnet 17 Yoke 18 Slider 19 Linear Scale 20 Stator 21 Pitch P Teeth 22 Electromagnet 23 Poles 24 Mirror Surface 25 Emitter 26 Light 27 Light Receiver 28 Light Receiver 29 Light Receiver

Claims (3)

[Claims] 1. A slider, which receives a force in one direction by a bias spring, has a position measuring mechanism and a stopping mechanism, and when the slider is driven by one intermittent drive unit and a signal is detected by the position measuring mechanism. When the energization is stopped, the position is fixed by the stopping mechanism, and the slider is driven to the final end, the stopping mechanism is held by the intermittent release mechanism, and the position measuring mechanism detects a signal confirming the holding, and then the When the slider is returned to the initial position and the slider returns to the initial position, the stop mechanism held by the intermittent release mechanism is returned by the return mechanism, and the position measuring mechanism operates again after detecting a signal confirming the return. By doing so, the intermittent drive device is characterized by performing continuous intermittent drive. 2. The locking mechanism is constituted by one or more pawl tooth racks, a pawl having a mirror surface that meshes with the pawl tooth rack, and a spring or a magnet for engaging the pawl with the pawl tooth rack. The intermittent drive device according to claim 1, which is characterized in that: 3. The position measuring mechanism comprises a light projector, two or more light receivers, and a mirror surface provided on the claw of the stop mechanism according to claim 2, and the light emitted from the light projector is provided on the claw. The optical receiver is arranged so as to receive light when the pawl meshes with the pawl tooth rack, when the pawl crosses the pawl tooth rack, and when the pawl is held by the intermittent release mechanism. The intermittent drive device according to claim 1, which is characterized in that: