JPS6048991B2 - stepping motor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a stepping motor.

More specifically, the present invention is directed to improved performance as a stepper motor designed for immediate starting and stopping. The acceleration capabilities of stepper motors often limit the motion that can be achieved in point-to-point positioning systems.

Transformer A entitled ``Characteristics of induction synchronous motors'' by A. E. Snowden et al.
IEE (Applications and Industries), March 1962, Volume 81, No. 1
With respect to conventional stepper motors of the type described on pages 5 to 5, such operation is limited, for example, by the large inertia of the rotor. In other conventional motors of construction such as that described in U.S. Pat. No. 3,169,200, such operation is particularly limited by the high reluctance of the flexible armature. When high-speed stepping of about 2000 steps per second is achieved using a permanent magnet or variable magnetic resistance stepping motor, which is typical at the current technological stage,
When starting and stopping the motor, the drive pulses are spaced apart,
It was necessary to use acceleration and deceleration circuits to prevent acceleration demands beyond the motor's capabilities.

For such special circuits, contact Icon Corporation of Cambridge, Massachusetts.
``Discrete Feedback Dynamic Control of Stepping Motors'' by D., W. Kennedy, published by
eedbackDynamjcControlofSt
eppingMotor).

However, this method is inconvenient because, in addition to complicating the motor control logic, additional conditions must be incorporated into the program to issue numerical commands to such a control system. According to the present invention, by giving the stepping motor a sufficiently large acceleration capacity,
The motion of the motor's output shaft can be controlled simply by turning on and off a pulse train at a constant frequency, avoiding the complications of special acceleration circuits and additional conditions that must be incorporated into the system programming as mentioned earlier. I'm here.

The main object of the present invention is therefore to provide a new and improved stepper motor which has the best performance within the limits defined by the materials of construction and which avoids the disadvantages of the prior art as mentioned above. It is to provide. In July 1971, the Institute of Electrical and Electronics Engineers (Institute of Electrical and Electronics Engineers) was established.
calandElectrOnjcEngineers
) published by the Joint Conference on Automatic Control (JOintAu
tOmaticCONtrOlCONference)
In a paper by the present inventor titled ``Performance Characterization of Point-to-Point Position Adjustment of Stepping Motors,'' which is a preliminary document for
The overall problem is to find reasonable criteria for the characterization of stepper motors, in order to be able to use a suitable device for driving a particular load. There is.

Solutions have been found for motors used for incremental adjustment, point-to-point positioning, and open-loop positioning;
There, the drive circuit used is capable of producing a motor current that is substantially square wave, and the motor must remain synchronized against abruptly applied changes in stepping frequency. It is assumed. Under these conditions, the motor has a work load per step Ws and a start/stop step when operated with no load. It has been found that it is characterized by two parameters: the upper limit of the twisting frequency Nuf. Considering these two parameters and load conditions as a measure, a method for determining the size of the motor can be determined. The load is specified in terms of its inertia, maximum required rotational speed, maximum allowable step size, and limits on the magnitude of frictional torque. Another result of this method is that after motor selection, the appropriate ratio of gears and links used to connect the motor to the load is determined. Further analysis of the above-mentioned paper reveals that, for the most part, the relative importance of the amount of work per step and the upper limit of the stepping frequency is a function of load, and that there is an obvious interchange between these two parameters. You can see that they are trying to avoid this. The load is poorly characterized by inertia and is represented by frictional torque, but by the product of the work per step and the upper limit of the stepping frequency (Wsl-
Nuf) completely determines the load driving capability of the motor. This product then provides a rough evaluation of the merits of the stepping motor. Note that the step size Sml, the torque rating Fml, and the inertia amount Mm are not important in themselves, but they become important if they are incorporated into the upper limit of the amount of work per step and the stepping frequency for starting and stopping. Designers of stepper motors should first try to obtain large values for work per step and upper limit of stepping frequency, but they should also try to obtain large values for the work per step and the upper limit of the stepping frequency, but not for other motors with comparable values for the first two parameters. The problem remains of obtaining another suitable design parameter for differentiation.

These other characteristics include motor size, heat loss due to I2R dissipation in the motor windings, inductance or energy stored in the windings (particularly that which cannot be converted into mechanical work), etc. , as well as other factors including longevity and reliability. A further object of the invention is therefore to minimize the size of the equipment required to obtain the desired level of work per step and upper limit of the stepping frequency, while at the same time achieving the other characteristics mentioned above. The aim is to keep it within a satisfactory range, in particular to prevent overheating of the motor and to keep the energy stored in the motor windings as low as possible (the latter being related to the voltage-current rating of the semiconductor drive components).

Another important factor in the operation of stepper motors is the time required for the output member and the load coupled thereto to come to its rest position after each step. This required time is correlated with the braking characteristics of the motor. In addition to the normal braking characteristics inherent in a motor with a particular configuration, it is often necessary to provide for other braking actions through external or internal means. A further object of the invention is therefore to provide a stepper motor with improved braking in an effective and simple manner. Further comparative studies have been conducted to see how the two key parameters, work per step and upper limit of stepping frequency, vary as a function of motor magnitude.

This research was based on the inventor's ``Point-to-point position control'' published by the American Society of Mechanical Engineers as a preparatory material for the 5th general meeting of the International Federation for Automatic Control (Bali, 2019). Performance of Variable Reluctance Stepper Motors for Adjustment. The conclusion of this paper is that the performance of a motor with an armature running perpendicular to the air gap is better than that of a motor with an armature running parallel to the air gap, allowing direct drive of electromechanical devices from the smallest device. It has been shown to be superior, even down to motor sizes that are much larger than those intended for use. In particular, this comparative study shows significant advantages of 1-5 for motion perpendicular to the air gap in a motor of dimensions representative of a stator diameter of about 10 cm (4 inches). Motion perpendicular to the air gap has been discovered to offer such advantages, so for commercial applications very small armature movements perpendicular to the air gap, such as vibrations, are required. It is important to find a practical solution to the inherent problem of converting the output elements of the device into unidirectional movements. Here, "perpendicular to one air gap" refers to a direction perpendicular to the air gap formed between the stator and armature from the armature to the stator, and perpendicular to one air gap. In short, the expression "move to" means that the armature is attracted in the direction of the stator due to the excitation of the stator. Furthermore, as can be seen in the explanation of the embodiments described below, if the output element is a rotating shaft, unidirectional motion refers to rotation of the shaft in one direction, either clockwise or counterclockwise. It is. In order to reduce the effects of armature inertia at the upper end of the stepping frequency, the practical design of stepper motors with motion perpendicular to the air gap has an armature displacement of 0.013 to 0.024 wt.
(stomach). 0.005 to 0.010 inch). However, to date, the full potential of the variable reluctance principle using motion perpendicular to the air gap over such a small range of displacement has not been practically realized. This is due to the lack of suitable means to convert such small displacements into unidirectional movement of the output element.
Some of the proposals according to the prior art use so-called harmonic drives with flexible gears, for example as already disclosed in US Pat. No. 3,169,200.
Such a structure is not useful for the purpose intended by the present invention.

This is because the relatively large air gap inherent in this construction occurs as the armature moves, at least at the reduction ratios used in many systems. There have also been proposals to use special gears in the form of gear loaders (gear rotors) as illustrated in U.S. Pat. However, substantial eccentricity results in a correspondingly large air gap. Therefore, this does not meet the intent of the present invention. Involute gear (U.S. Patent No. 3,585,425, 3)
No. 585,426) to control the output shaft at a reduced speed by the use of a nutating armature motion (U.S. Pat.
22984) and plate armatures for armature operation. Previous proposals, such as those implementing a bent armature driving a rotating swashplate, may likewise be used to determine the desired degree of gear reduction (in the case of a bent armature shaft) or form the basis of the present invention. In some cases, excessive armature movement is required relative to the desired optimal performance criteria. From this point of view, it cannot be applied to solving the problem of the present invention. The use of a rotating armature (such as that described in U.S. Pat. No. 2,437,904) also limits the size of the air gap relative to the ratio of gears and the size of the device. becomes excessive.

In a device of the type disclosed in U.S. Pat. 5 is required. According to the invention, unlike these devices with large air gaps and attendant disadvantages, the armature moves at right angles to the air gap and is substantially in contact with the stator at its closest location. It has an oscillatory motion that is amplified by a mechanism arranged to operate in parallel, part of which is connected non-rigidly or flexibly to the armature, thus meeting the performance criteria underlying the present invention. , with significantly improved performance, along with the smallest air gap and other dimensions.

Another object of the invention is therefore to provide a device which advantageously solves the problem of effectively converting the movement of the armature into the movement of the output element.

As will be seen below, this conversion involves first amplifying the armature motion using a suitable link, which in turn provides a device for converting the armature motion into a unidirectional motion of the output element. drive Other further objects of the invention are set forth below and particularly pointed out in the appended claims.

That is, the present invention provides a housing, a stator having a plurality of magnetic poles fixed to the housing,
a winding connected to a power source to magnetize the magnetic poles of the stator; and an armature that is attracted to the magnetic poles and moves within the stator in a direction that substantially changes the thickness of the air gap between the magnetic poles. an armature arranged such that its axis moves about a stator axis; an output element supported by the housing; and an output element non-rigidly coupled to and responsive to the armature. It consists of a rotating shaft that moves in a conical manner, and a conversion member that has a set of gears and converts the movement of the rotating shaft into rotation of the output element in one direction. The stepping motor is configured such that the thickness of the stepper motor varies from substantially zero to a few thousandths of a centimeter. A detailed description of the preferred embodiment follows. The present invention will be described below with reference to the accompanying drawings.

To explain the embodiment of the present invention shown in FIG.
The figure shows a cross-sectional view of a portion of the device of the present invention and a side view of the other portion.

In the figure, the stator 1 has a slot 1A in which a winding 13
have. The current flowing through these windings 13 magnetizes the stator teeth such as 1B. An armature 2 having an outer diameter smaller than the inner diameter of the stator 1 is provided inside the stator 1.
The output element of the device is a shaft 8 which is held by bearings 9 and 10 contained in the leftmost bell 12. The shaft 8 is tilted according to the deflection of the thin metal washer, and is driven by an internal gear 5 via an off-axis rotating shaft 4 and a universal joint 7. The armature 2 is attracted to the side of the stator which excites one or more windings. The excitation is carried out by means of suitable circuits and connections of the windings with phases derived therefrom, such that the positions of the magnetic poles are successively shifted along the circumferential surface of the stator, as will be explained later. This in turn attracts the armatures to the sides of the stator, causing the interior of the stator to rotate. The armature axis will therefore move around the stator axis. Then, the rotating shaft 4 non-fixedly connected to the armature by a bearing 3 disposed inside the armature 2 performs a conical movement with the joint 7 as the apex, and the internal gear 5 is connected to the inner circumference of the external gear 6. is engaged with the same gear 6 at the point where it rotates. The external gear is fixedly held on the bell 11 on the opposite side, that is, on the right end, and since the internal gear 5 has fewer teeth than the external gear 6, the movement of the rotating shaft causes the internal gear to move between these two gears. It will rotate at an angle j corresponding to the difference in the number of teeth. Therefore, this causes the rotating shaft 4 to rotate, and this rotation is transmitted to the output shaft 8 via the universal joint 7. This engagement and disengagement of the internal and external gears must not occur even if the magnetic force acts to separate this engagement at a time when the output'' element is significantly delayed from the angle commanded by the magnetic force.

This is because if disengagement occurs, synchronization will be lost. To this end, the tooth profile of the external and internal gears 6, 5 and the number of teeth on each gear are such that the internal gear can be disengaged by the support (bridging effect) provided by the teeth of either of the engagement points or meshing points. Selected to be prevented. In another method, engagement and disengagement can be prevented by attaching to the rotating shaft 4 a tip 4A that moves around a similar stationary tip 4B provided on the end bell 11. These chips must be made very small in real devices;
It is also preferable that it be made of a very hard material such as diamond or sapphire. The third way to prevent disconnection is to
The gear is shaped so that the tip of the tooth of the internal gear at a location directly opposite the engagement point of the gear passes the tip of the tooth of the external gear at that location with almost no gap between them. The internal gear is thus supported in this case by the contact between the tips of these two teeth and moves slightly in the direction of engagement when a force is applied. The above-mentioned "gear rotor" type gear is one of the gears whose engagement and disengagement are prevented by this method.In the embodiment shown in Fig. The thickness varies approximately sinusoidally on the side of its average value as a function of the angle of the tangent of the rotating contact between armature 2 and the internal surface of stator 1, and the relative difference between the stator and armature diameters The smaller the difference, the more accurate the approximation.

For each rotation of the tangent of the contacts and corresponding rotation of the point of engagement between the inner and outer gears, there is a full cycle of change in the thickness of the air gap under each pole. For this reason, gear 5
and 6 cooperate with the rotating shaft 4 and the universal joint 7 to change the thickness of the air gap transmitted through the armature 2, shaft, and receiver 3 and amplified by the rotating shaft 4 to a single output shaft 8. Convert to unidirectional rotation. In particular, the conversion means represented by components 5, 6, 4 and 7 convert the oscillatory movement of the armature 2 after being amplified by the rotary shaft 4 into a unidirectional movement of the output shaft 8. The unidirectionality persists for at least 112 cycles of armature oscillatory motion. It can be seen from FIG. 1 that the rotating shaft 4 functions as a lever and its fulcrum is located at the center of the universal joint 7.

This lever mechanically amplifies the radial movement of the armature 2, i.e. the movement perpendicular to the air gap, to produce a sufficient displacement so that a sufficient movement of the internal gear 5 is achieved. The combination of the two gears 5 and 6 is the output shaft 8
Converting the vibrational motion of the rotating shaft 4 represented by the rotation of an axis protruding from a cross section or other surface including the axis into a rotational motion,
The rotational movement of is then transmitted to the output element.

In the simplest embodiment of the device, the windings 13 passing through several slots in the stator are connected to four phases.

The drive circuit operates so that the phase currents are either ozo or ob. In response to pulses sent to the drive circuit, two phases are always energized, or on, and two phases are always off. For example, when phases ゛゜1゛ and ゜゜2゛ were initially energized, a pulse corresponding to forward rotation is formed in these two phases. When received, phase ゜゜1゛ is turned off and phase ゜゜3゛ is turned on. The next forward rotation pulse turns off phase ``゜゜゛ and turns on phase ``゜゛.'' And so on. Such a succession of phase currents advances the equilibrium position of the rotation line of the armature-stator contacts in 90 degree steps, and the engagement points between the internal and external gears move accordingly. A circuit suitable for continuously passing a winding current is described, for example, in U.S. Pat.
No. 402,334. As another example, the number of phases used may be three for unidirectional phase current, or
The number is greater than four.

Note that the number of phases that can be excited simultaneously at any time is at least one, and may be two or more.
In order to allow the armature 2 to rotate smoothly inside the stator 1 despite the gaps in the cylindrical inner surface due to the slots, it is desirable to provide rollers 14 and 14A at both ends of the armature.

These rollers have a diameter slightly larger than the outer surface of the ferromagnetic portion of the armature. These rollers of the armature are
It makes contact with races 16 and 16A attached to end pieces 17 and 17A of stator 1. The roller and lace materials may be the same or dissimilar;
Generally not ferromagnetic. Plastic materials may be used to reduce the weight and noise of these parts. The second part forms a smooth path for rotating the armature.
The method is to fill the stator slots with a suitable material after inserting the windings and then machine or grind the stator bore into a perfectly round cylindrical surface.

However, in this case, care should be taken to avoid distortion of this surface due to temperature changes, such as by using a filler material with a coefficient of thermal expansion close to that of the magnetic material of the stator.
Yet another way to achieve smooth rotational movement of the armature is to bend the laminated slot so that the rotational tangent closes it.

A suitable device for doing this is such as shown in the exploded view of the bore of the stator 1 in FIG. Contains a double bent slot 1A. The 7-slot bend allows the rotational tangent to proceed smoothly, which is particularly advantageous when the winding is excited using complex methods such as the use of non-square wave currents.

In the configuration of FIG. 1, it is important that the rotation of the armature per revolution of the line of contact with the stator is smaller than the rotation of the internal gear 5 and the output element 8.

This is due to the amplification of the radial movement caused by the rotating shaft 4. For this purpose, the bearing 3 must provide angular freedom of the rotating shaft 4 with respect to the armature 2 as well as relative rotation. Since the radial movement of the electric bar is small compared to the distance from the center of the universal joint 7 to the center of the bearing 3, the angular movement of the rotating shaft 4 is sufficient to allow a conventional ball bearing to be used as the bearing 3. It's getting smaller.
The stator 1 and the armature 2 can be made from solid or laminated ferromagnetic material or by molding from powder.

For various applications, these parts are most preferably laminates of high quality magnetic material. However, for applications that do not require maximum performance, using a laminated material for the stator and a solid material for the armature will help reduce costs. When driving certain types of loads, especially loads with large inertia, the braking action of the stepping motor itself shown in Figure 1 is suitable for rapidly damping the transient vibrations of the output element that occur immediately after a sudden start or stop. is insufficient. Therefore, another braking action is introduced by the means shown in FIG. 2, in which the external gear 6 is provided inside an elastomer cup 6A, and this elastomer cup
It is attached to 1. Such a non-permanent mounting method of the external gear 6 reduces the cyclic fluctuations of the output element under transient conditions of starting or stopping. With proper selection of the elastomer material, sufficient energy is used as a result of this slight movement to substantially increase the effective braking force of the device. If the braking force obtained in this way is still insufficient, the alternative is to suspend the external gear 6 on a flexible or other J-type bearing and connect it to an auxiliary electromagnetic or mechanical coupling. Or it may be connected to a viscous friction braking mechanism. FIG. 3 shows another form or modification of the invention in which the inertia of the armature is even lower, and in some respects the performance is better than that obtained with the arrangement of FIG.

Instead of a cylindrical armature, the configuration specified in FIG.
using two armature segments. One of them is designated as 19, and its paired armature is shown in an axial sectional view 4. These armatures have a flexure pivot of 20
supported above. Stator 18 consists of four magnets of two poles each, one of which is designated 19A. Third
Figure A is a sectional view of the stator and armature on a cross section perpendicular to the axis of the device. Each pole has an excitation winding, such as winding 34. The free end of each armature is extended 7 such that the armature and its extension constitute a lever for mechanically amplifying the movement of the armature. These motions are transmitted by push rods 24 or the like to a rotating shaft 33, which further amplifies the armature motion as it transmits the rotary motion to an internal gear 28 provided at its end. This internal gear 2
8 is the outer 9-part gear 27 at the hollow end of the output element 26
interlock with each other. The shaft of the output element 26 is supported in bearings 35 and 36 in the end bell 23. The internal gear 28 is prevented from rotating by a lug provided on the hub 29.
The hub 29 engages a slotted ring 30 which is gripped by lugs on a stationary reaction member 31 fixed to the central support 32. This mechanism for preventing rotation of the internal gear is shown in detail in FIG. The internal gear 28 is arranged axially by a rotating shaft 33 with a spherical pivot 25 so as to be able to rotate under the influence of forces transmitted from the armature via the push rod 24. Lubricating oil for all these parts is provided by a flexible boot 3 held by clamps 37A and 38.
7 and shaft seal 39, it is confined in a central portion surrounding gears 27 and 28. The central support 32 is installed between the bells 21 and 23 after all the parts associated with the armature have been provided. Figures 3, 3A and 4
The operation of the stepper motor according to the illustrated embodiment of the invention is similar to the operation of the embodiment of FIG. 1 as far as the overall transmission of force from the winding current to the rotation of the output element is concerned.

The operational difference is that the armature oscillates rather than rotating as a cylinder inside the stator. By amplifying using the lever principle, the vibration of the armature is reduced to the push rod 2.
4, etc., into a rotational motion of the rotating shaft 33. This rotational movement is further amplified by the rotating shaft 33 to drive the internal gear 28. Since the internal gear is configured to be non-rotatable, each rotation of the external gear 27 at the point of engagement must be rotated by the difference in the number of teeth on these two gears. The engagement and disengagement of these gears is prevented by suitable means as previously described in connection with the first embodiment of FIG. FIG. 5 shows an alternative means for configuring internal gear 28 to be non-rotatable. In this case, rotation of the gear 28 is prevented by meshing with another internal gear 40 and another external gear 41. gear 28
The teeth of gears 40 and 41 have a modified shape, unlike conventional involute or gerotor teeth or other suitable tooth profiles used in gears 40 and 27. In other words, these gears are
Despite the difference in pitch diameter, they have the same number of teeth. Here, the external gear 41 is fixedly arranged. Since gears 40 and 41 have the same number of teeth, even if their meshing points rotate, the rotation of internal gears 40 and 28 is zero. The embodiment of FIG. 6 shows another form of electromagnet and armature that may be used in various forms of the invention.

By extending the pole pieces of the electromagnet shown earlier,
An electromagnet 57 having the shape shown in FIG. 6 is obtained. This electromagnet is energized by windings such as coils 59 and 60.
Furthermore, the armature 58 has a trapezoidal cross section and is designed to close the gap between the magnetic poles 61 and 62 when it is fully shifted upward. This electromagnet and armature configuration is preferred for applications requiring high performance because the armature has little inertia. 7th
The figure is a cross-sectional view of an embodiment of the invention similar to FIG. It has been modified so that it can be driven by the end extending from the bell 11 without the need for gearing from the bell.

This configuration through which the shaft passes can be achieved by using a hollow rotating shaft 4 as shown in FIG. 7 in place of the hollow shaft shown in FIG. The modified configuration of Figure 7 does not use rollers or races to provide a smooth path for the rotating armature, but instead fills the slots in the stator or as in the type shown in Figure 1A. It uses double-folded laminations. Also, in place of the universal joint 7 of the configuration of FIG. 1, the configuration of FIG. 7 uses a diaphragm type flexible coupling 7 to perform this function. In some applications of the invention, it is ensured that the armature does not tilt and become rotated with an axis that is not parallel to the axis of the output shaft.

This is because there is an axial force or noise resulting from the tendency to thread the armature axially along the stator bore.
In an example of preventing such tilting of the armature, two methods for preventing it are shown in FIGS. 8 and 9. 8th
In the configuration shown, the problem of armature tilting is avoided by not rotating the armature over the stator bore.

Armature 2 is restrained by another hanging element and stator 1
rotates without touching the This is done by extending the tubular extension 2A to the support for the armature stack, which terminates in a diaphragm-type flexible pivot 2B. If the stator bore is cylindrical, the armature surface is conical, and vice versa, and the substantially parallel surfaces of these two are the most It is designed to be obtained in close proximity. Another way to eliminate the ambiguity of the armature axis position associated with support by a single bearing 3 of FIGS. A modification of the configuration of FIG. 8 may be used using ball bearings or other bearings designed to accommodate small angular movements.

According to this embodiment, the armature can rotate while pivoting, and the air gap can be zero for at least one point of contact with the stator bore. In Figure 8, if the air gap across the contact points can be minimized,
Although the noise increases slightly, the mechanical performance of the entire device is improved. If the armature is supported for both pivoting and rotation, the armature surface is designed in relation to the stator bore and in rolling contact over a narrow annular band, preferably bearing 3. It must be ensured that no unnecessary slip occurs due to contact near the plane of the surface. This can be accomplished by using a cylindrical stator bore and a slightly crowned, generally conical armature. In the embodiment of FIG. 9, the central portion of the armature is formed in the form of a ring 63 of solid material with an internal groove, thereby allowing rotation while preventing the armature from tilting.

The stator 1 also includes a central member 64 supporting a plurality of equally spaced pins. These pins have flattened ends 66 which act as keys to engage grooves in the armature ring 63. This configuration allows the armature to rotate but is restrained from tilting. Lubrication can be accomplished by placing the wick 67 in a hole drilled in a pin with a small groove to allow oil to flow to the end 66. Also, the gears 5 and 6 are lubricated by a plurality of felt plugs 68 arranged so as to be in contact with the internal gear 5. Lubricating these parts is done with grease or other suitable lubricating oil. In summary, all embodiments employing the techniques of the present invention utilize an electromagnet and an armature in which the motion of the armature is perpendicular to the air gap or has components perpendicular to the air gap. , the thickness of the gap can be changed.

These electromagnets and armatures are the means for converting electrical energy into mechanical motion. To be useful in stepper motors, these electromagnets and armatures must have a small armature motion compared to the normal motion of the armature of a common relay or similar device. It is. In order to effectively convert this small armature movement into a unidirectional movement of the output element, the small oscillatory movement of the armature is first amplified by the use of a lever or the like, and then this amplified movement is converted into a unidirectional movement of the output element. is converted into unidirectional motion. An apparatus constructed according to the embodiment of FIG.
When operated and tested using the two-phase off method, the following results were obtained.

Resistance, 21 for each of the 4 phases Inductance, 21 for each of the 4 phases, C, L0.027H Number of stator poles 16 Step size Sm6 Moment of inertia Mm67.8grTl/
Current per d phase: 12.0A. At low step speeds for torque, friction loads, Fm l. 4×10-6dyn/CTft Upper limit of stepping frequency, start-stop, Nllf 8O(g)Ec-1 Work amount per step, WSO. Ol5J production power,
WSNUfl2W maximum continuous stepping frequency, slow acceleration 1330sec-
1 Maximum stepping frequency, start-stop, inertia load 21
At 0grr1/d, the power per step for the stored magnetic energy per phase of the present device is 0.28.

This is higher than many other current technology devices and means that the new device is easier to drive than other devices with comparable power per step. The above data assumes that the motor power supply voltage is 58 novolts,
Connect a 25 ohm resistor in series to each phase of the motor and R.
A. Written by R.A. Yacke as preparatory material for a symposium and published by B.C.
“Incremental Motion Control Systems and Devices 2’ (Incremental Motion Control Systems and Devices 2’) edited by Professor KuO and published by the University of Illinois Department of Electronic Engineering in March with 197 reviews.
'6 Step Motors and Controls'3 of Part 1 of the paper entitled SystemandDevice)
15 of (StepMOtOrandCONtrOls)
The data was obtained using a standard transistor circuit for driving a device of the type shown in Figure 3 on page 5. A 125 ohm snapping resistor was used to develop a collector peak voltage of 250 volts to the output power transistor.

The outer diameter of the armature is approximately 3C7T1 (1.629 inches),
Length is 2.7 cm (1.310 inches), thickness is 0.2
cm(4). 100 inches). The maximum and minimum amplitude of armature movement was 0.025 crfL (0.017 inch). The amplification factor provided by the lever action of the rotary shaft 4 was 5.18. External gear 5 has (1) teeth, and internal gear 6 has 64 teeth. These gears were involute tooth type gears with a diametric pitch of 64 and a pressure angle of 20 degrees. It goes without saying that many other variations in the design of the amplifier, converter, and the like are possible, and the invention is not limited to the specific embodiments shown here. It is intended that the scope and spirit of the invention be understood by the appended claims, including all such modifications and changes as may occur to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a preferred configuration of a motor incorporated in the present invention using an armature rotating inside a stator. FIG. 1A is a developed view of the inner surface of the stator used to obtain smooth rotational movement of the armature; FIG. 2 is a sectional view of the braking means used to provide the internal gear structure of FIG. 1;
FIG. 3 is a longitudinal cross-sectional view of a modified motor configuration with a segmented armature, and FIG. 3A is another cross-sectional view of the modified motor of FIG. 3, viewed perpendicular to the longitudinal axis of the device. Figure, 4th
Figure 5 is a perspective view of a mechanism for preventing rotation of the internal gear of a vibrating unidirectional motion conversion device, and Figure 5 is a perspective view showing a modified means for keeping the internal gear stationary against rotation. , FIG. 6 is a cross-sectional view of the magnetic components used to obtain the low armature inertia useful in the embodiment of the configuration of FIG. 3, and FIG. 7 is similar to FIG. 1 but with the axis passing through. FIG. 8 is a cross-sectional view of another embodiment of the invention using the "rotating armature" configuration of the present invention and equipped with an output member. Sectional View, FIG. 9 is a cross-sectional view of an alternative configuration similar to the embodiment of FIG. 1, but with an anti-tilt mechanism for the armature: 1 . . . stator, 1
A...Slop, 1B...Tooth, 2...
Armature, 2B...Flexible pivot, 3...
Bearing, 4...Rotating shaft, 4A, 4B...
・Tip, 5... Internal gear, 6... External gear, 6A... Elastomer cup, 7... Universal joint, 8... Shaft, 9...・・・・・・
Bearing, 10... Bearing, 11... Bell, 12... Bell, 13... Winding, 18... Stator, 19... Armature , 19A...Electromagnet, 20...Bending pivot, 21...Bell, 23...Bell, 24...Push rod, 25...
... Spherical pivot, 26 ... Output element, 27.
... External gear, 28 ... Internal gear, 29 ... Hub, 30 ... Ring, 31 ... Stationary reaction member, 3
2... Central support, 33... Rotating axis, 34
...Winding, 37...Flexible boots, 37A,
38... Clamp, 39... Shaft seal, 40... Internal gear, 41... External gear,
43-46... Magnet, 47, 48... Push rod, 47A, 48A... Lever, 49A, 50A
...Push rod, 49,50 ...Ball bearing, 51,52 ...Bearing, 53 ...Shaft, 54 ...Zenion, 55 ...Rack, 56A,
56B... Armature, 57... Magnet, 58.
... Armature, 59, 60 ... Coil, 61,
62...Magnetic pole, 63...Ring, 64...
...Central center member, 66...End part, 67...
...Toshin.

Claims (1)

[Claims] 1 Thickness of the air gap between a housing, a stator with a plurality of magnetic poles fixed to the housing, a winding connected to a power source to magnetize the magnetic poles of the stator, and a magnetic pole attracted by the magnetic poles. an armature for movement within the stator in a direction that substantially changes the height of the stator; the armature is disposed such that its axis moves about an axis of the stator; an output element, a rotating shaft that is non-fixedly connected to the armature and moves in a conical manner in response to the armature, and a set of gears to direct the movement of the rotating shaft in one direction of the output element. 1. A stepping motor comprising a conversion member for converting rotation into rotation, and configured such that the change in the thickness of the air gap due to displacement of the armature is from substantially zero to several thousandths of a centimeter.