JP2003023796A - Method of calculating constraint current of dc motor, method of manufacturing dc motor and apparatus for manufacturing dc motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a DC motor which can easily obtain characteristics at a low cost, and moreover can easily manufacture the DC motor at a low cost. SOLUTION: In a rush current measuring process, the DC motor is driven with application of voltage, after assembling of motor components of measure the rush current, when the motor is driven. In a constraint current calculation process, a constraint current I1 is calculated with the rush current and prescribed constants obtained in advance. After the rush current measuring process, in a non-load current measuring process, when rotation is stabilized under the non-load condition, a non-load current I0 is measured. After the rush current measurement process, in a process of measuring the number of revolutions under the non-load condition, the number of revolutions N0 under the non-load condition is measured when the rotation is stabilized under the non-load condition. After the current measurement process and process to measure the number of revolutions under the non-load condition in an induced voltage measuring process, application of voltage is stopped and an induced voltage under this condition is measured. In a characteristic calculation process, a constraint torque T1 is calculated, based on the constraint current I1, a non-load current I0, number of resolutions under the non-load condition N0 and induced voltage is calculated, to obtain the characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for calculating a restricted current for a DC motor, a method for manufacturing a DC motor, and a manufacturing apparatus for a DC motor.

[0002]

2. Description of the Related Art A DC motor is tested at the time of its manufacture for each characteristic to meet the user's demand, and a product that passes the test is regarded as a product. Therefore, each characteristic of the DC motor is measured during manufacturing. The characteristics of this DC motor include the rotation speed / current value-torque characteristic (see FIG. 3). Then, as a method of obtaining this characteristic, after assembling the motor parts, a voltage is applied to start the motor, a mechanical load is applied to the rotating shaft, and a current value is measured by the current sensor, the rotation sensor, and the torque sensor, There is a method of measuring the rotation speed and the torque.

[0003]

However, the above method requires a load applying device (electromagnetic brake or the like) for mechanically applying a load, or a torque sensor (torque-voltage converter or the like). However, there is a problem that the measuring device becomes complicated and the cost becomes high.

Therefore, Japanese Unexamined Patent Publication No. 9-97027 discloses a technique capable of obtaining characteristics without requiring a load applying device (electromagnetic brake or the like) or a torque sensor (torque-voltage converter or the like). There is. In this method, the restraining current (current when restrained) is measured in a state before the stator magnetic poles are not magnetized (non-magnetized state), or the winding resistance is measured by the rotor alone and restrained using the resistance value. Calculate the current. Then, after the motor parts have been assembled (after magnetization), the no-load current, the no-load rotation speed, the induced voltage, etc. are measured and calculated from each value (including the restricted current) to obtain the characteristic (see FIG. 3) .

However, in the above method (Japanese Patent Laid-Open No. 9-197027), there is a step of measuring before assembling the motor parts (before magnetizing) and after assembling the motor parts (after magnetizing). It will be necessary. Therefore, there is a problem that the number of manufacturing steps of the DC motor increases and becomes complicated, and the manufacturing cost increases. or,
When re-measurement is performed after assembling the motor parts, disassembling and re-assembling are required.

A first object of the present invention is to provide a method of calculating a restricted current that can easily obtain a restricted current of a DC motor at low cost. A second object is to provide a DC motor manufacturing method and a DC motor manufacturing apparatus that can easily obtain characteristics at low cost and can easily manufacture a DC motor at low cost. It is in.

[0007]

According to a first aspect of the present invention, there is provided a method for calculating a restricted current of a DC motor, which calculates a restricted current of the DC motor based on an inrush current of the DC motor and a predetermined constant determined in advance. Use as a summary.

According to a second aspect of the present invention, in the method for calculating the restricted current of the DC motor according to the first aspect, the predetermined constant is obtained by measuring the inrush current and the restricted current from a plurality of DC motors of the same type and the same type, Obtained based on both of these measurements.

According to a third aspect of the invention, a step of measuring a rush current at the time of starting by applying a voltage after assembling the motor parts and measuring the rush current at the time of starting, the rush current, and a predetermined predetermined value A constraint current calculation step of calculating a constraint current with a constant, a no-load current measurement step of measuring a no-load current when the rotation under no load is stable after the inrush current measurement step, and the inrush current measurement step After that, the no-load rotation speed measurement step of measuring the no-load rotation speed when the rotation under no load is stable, and the application of voltage is stopped after the no-load current measurement step and the no-load rotation speed measurement step. Then, the induced voltage measurement step of measuring the induced voltage at the time of the stop, the constraint current is calculated based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage, and the characteristic to specify the characteristic. With calculation process And gist of the production method of the direct current motor.

According to a fourth aspect of the present invention, in the method of manufacturing a DC motor according to the third aspect, the predetermined constant is
The inrush current and the restraint current are measured from a plurality of DC motors of the same type and the same type, and obtained based on the both measured values.

The invention according to claim 5 is the invention according to claim 3 or 4.
In the method for manufacturing a DC motor according to the item [4], the no-load rotation speed measurement step calculates a no-load rotation speed from a current pulsation component of the no-load current.

According to a sixth aspect of the invention, a rush current measuring means for measuring a rush current at the time of starting by applying a voltage after assembling the motor parts, the rush current, and a predetermined predetermined value. A constraint current calculating means for calculating a constraint current by a constant and a no-load current measuring means for measuring a no-load current when the rotation is stable under no load after measuring the inrush current, and the inrush current is measured. After that, a no-load rotation speed measuring means for measuring the no-load rotation speed when the rotation under no load is stable, and after measuring the no-load current and the no-load rotation speed, stop the application of voltage, Induced voltage measuring means for measuring the induced voltage at the time of the stop, characteristic calculating means for calculating the restraint torque based on the restraint current, the no-load current, the no-load rotation speed, and the induced voltage to specify the characteristic Direct current And gist other manufacturing equipment.

According to a seventh aspect of the invention, in the DC motor manufacturing apparatus according to the sixth aspect, the predetermined constant is
The inrush current and the restraint current were measured from a plurality of DC motors of the same type and the same type, and obtained based on the measured values.

The invention according to claim 8 is the invention according to claim 6 or 7.
In the apparatus for manufacturing a DC motor described in (3), the no-load rotation speed measuring means calculates the no-load rotation speed from the current pulsation component of the no-load current.

(Operation) According to the invention described in claim 1,
Since the binding current of the DC motor is calculated by the inrush current of the DC motor and the predetermined constant obtained in advance, for example,
Even after assembling the motor components, it is possible to easily obtain the restricted current at low cost.

According to the second aspect of the present invention, since the predetermined constant is obtained based on the measured values of the inrush current and the restricted current from a plurality of DC motors of the same type and the same type,
It is possible to easily obtain a highly reliable constant.

According to the third aspect of the invention, in the inrush current measuring step, a voltage is applied and activated after the motor parts are assembled, and the inrush current at the time of activation is measured. Then, in the constraint current calculation step, the constraint current is calculated from the inrush current and the predetermined constant determined in advance. And
After the inrush current measurement step, in the no-load current measurement step,
The no-load current is measured when the rotation is stable under no load. Then, after the inrush current measurement step, in the no-load rotation speed measurement step, the no-load rotation speed when the rotation under no load is stable is measured. Then, after the no-load current measuring step and the no-load rotational speed measuring step, in the induced voltage measuring step, the voltage application is stopped, and the induced voltage at the time of the stop is measured. Then, in the characteristic calculation step, the constraint torque is calculated based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage, and the characteristic is specified. Therefore, it is not necessary to use a load applying device (electromagnetic brake or the like) or a torque sensor (torque-voltage converter or the like) for mechanically applying a load, and the characteristics can be obtained after the motor parts are assembled. Further, the characteristics can be obtained by only applying and stopping the voltage once after assembling the motor parts. Thus, according to this method, the characteristics can be easily obtained at low cost, and the DC motor can be easily produced at low cost.

According to the invention as set forth in claim 4, since the predetermined constant is obtained based on the measured values of the inrush current and the restricted current from a plurality of DC motors of the same type and the same type,
It is possible to easily obtain a highly reliable constant.

According to the fifth aspect of the invention, the no-load rotation speed is calculated from the current pulsation component of the no-load current in the no-load rotation speed measurement step. So with this method,
Each characteristic can be obtained at low cost without requiring a mechanical rotation sensor or the like.

According to the sixth aspect of the invention, the inrush current measuring means starts the application of a voltage after the motor parts are assembled, and the inrush current at the time of starting is measured. Then, the restraining current calculating means calculates the restraining current from the inrush current and the predetermined constant determined in advance. And
After the inrush current is measured, the no-load current measuring means measures the no-load current when the rotation under no load is stable. After the rush current is measured, the no-load rotation speed measuring means measures the no-load rotation speed when the rotation under no load is stable. Then, after the no-load current and the no-load rotation speed are measured, the induced voltage measuring means stops the application of the voltage, and the induced voltage at the time of the stop is measured. Then, the characteristic calculation means calculates the constraint torque based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage, and the characteristic is specified. Therefore, it is not necessary to use a load applying device (electromagnetic brake or the like) or a torque sensor (torque-voltage converter or the like) for mechanically applying a load, and the characteristics can be obtained after the motor parts are assembled. Further, the characteristics can be obtained by only applying and stopping the voltage once after assembling the motor parts. As a result, with this device, the characteristics can be easily obtained at low cost, and by extension, the DC motor can be easily manufactured at low cost.

According to the seventh aspect of the invention, the predetermined constant is obtained based on the measured values of the inrush current and the restricted current measured from a plurality of DC motors of the same type and the same type. , The constant reliability is high, and the constraint current can be calculated with high accuracy.

According to the eighth aspect of the present invention, the no-load rotation speed is calculated from the current pulsation component of the no-load current by the no-load rotation speed measuring means. Therefore, this manufacturing apparatus does not require a mechanical rotation sensor or the like, and each characteristic can be obtained at low cost.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, a DC motor manufacturing apparatus (characteristic measuring apparatus) includes a current sensor (ammeter) 1, a personal computer (hereinafter referred to as a personal computer) 2, a power supply 3, and a switch 4. The personal computer 2 includes a current measuring unit 5, a calculating unit 6, a voltage measuring unit 7, and an output unit 8.

In the present embodiment, the current sensor 1, the personal computer 2 (specifically, the current measuring unit 5 and the arithmetic unit 6), and the switch 4 constitute inrush current measuring means. Further, in the present embodiment, the current sensor 1 and the personal computer 2 (specifically, the current measuring unit 5 and the calculating unit 6) constitute a no-load current measuring means and a no-load rotation speed measuring means. Further, in the present embodiment, the personal computer 2 (specifically, the calculation unit 6) constitutes the constraint current calculation means and the characteristic calculation means.
In addition, in the present embodiment, the personal computer 2 (specifically, the arithmetic unit 6 and the voltage measuring unit 7) and the switch 4 constitute an induced voltage measuring means.

The power source 3 has its low potential side power source connected to the first terminal 11 via the current sensor 1 and its high potential side power source connected to the second terminal 12 via the switch 4.
The current sensor 1 is connected to the personal computer 2 (current measuring unit 5). The first and second terminals 11 and 12 are connected to the personal computer 2 (voltage measuring unit 7).

The current sensor 1 sends an analog signal S1 (voltage signal) corresponding to the current value to the personal computer 2 (current measuring section 5).
Output to. The personal computer 2 performs various processes by performing a predetermined operation.

In the personal computer 2, the current measuring section 5 converts the signal S1 into a digital current value signal S2 and outputs the current value signal S2 to the computing section 6. Further, in the personal computer 2, the voltage measuring unit 7 has the first and second terminals 11, 12
The digital voltage value signal S3 corresponding to the voltage between
Output to.

Further, in the personal computer 2, the arithmetic unit 6 has predetermined constants α and β inputted in advance, performs various arithmetic operations, and outputs the arithmetic results to the output unit 8. The calculation of the calculating unit 6 will be described in detail in a method of manufacturing a DC motor (characteristic measuring method) described later, and a detailed description thereof will be omitted here.

Further, in the personal computer 2, the output unit 8 is connected to an external monitor (not shown) to display the calculation result on the monitor. A DC motor manufacturing method (characteristic measuring method) performed by the DC motor manufacturing apparatus (characteristic measuring apparatus) configured as described above will be described.

In the present embodiment, the inrush current It and the restraint current Il are measured in advance from 30 completed DC motors of the same type and same type (characteristics of which are determined to meet the demands of users, etc.), and both measured values are measured. The predetermined constants α and β are calculated based on The constants α and β are constants for calculating the constraint current Il from the inrush current It (so-called regression analysis), and are calculated so as to satisfy the following formula (A).

Il = α × It + β Equation (A) Then, as shown in FIG. 1, first and second terminals 1
The power source input terminals of the DC motor M are connected to 1 and 12.
The DC motor M described here is one in which motor parts are assembled (the magnetic poles of the stator are magnetized),
Its properties have not been measured.

[Inrush current measuring step] Next, in the "inrush current measuring step", the current sensor 1 and the personal computer 2 (more specifically, the current measuring section 5 and the calculating section 6) and the switch 4 which constitute the inrush current measuring means are connected. Then, a voltage is applied to the DC motor M to start it, and the inrush current It at the time of starting is measured.

Specifically, the switch 4 is turned on to start the DC motor M with no load. Then, as shown in FIG. 2, the computing unit 6 measures the maximum inrush current It from the current value (current value signal S2) immediately after the start input through the current sensor 1 and the current measuring unit 5. .

"Binding current calculating step" Next, in the "binding current calculating step", the calculating unit 6 constituting the binding current calculating means uses the inrush current It and the predetermined constants α and β to set the binding current. Calculate Il.

More specifically, the computing unit 6 solves the equation (A) based on the measured inrush current It and the predetermined constants α and β to calculate the constraint current Il. "No-load current measurement process" Next, "No-load current measurement process"
Then, the current sensor 1 and the personal computer 2 (specifically, the current measuring unit 5 and the arithmetic unit 6) that constitute the no-load current measuring means measure the no-load current Io when the rotation is stable under no load.

More specifically, as shown in FIG. 2, in the calculation unit 6, the current value when the current value (current value signal S2) input via the current sensor 1 and the current measurement unit 5 is stable is not calculated. It is measured as the load current Io.

"No-load rotational speed measuring step" Next, in the "no-load rotational speed measuring step", the current sensor 1 and the personal computer 2 (more specifically, the current measuring section 5) constituting the no-load rotational speed measuring means.
And the calculation unit 6) measures the no-load rotation speed No when the rotation under no load is stable.

More specifically, the calculation unit 6 calculates the no-load rotation speed No from the current pulsation component of the no-load current Io.
Here, since the current pulsation component is generated in correspondence with the number of slots of the armature core of the DC motor M, no load is generated by dividing (dividing) the number of times of current pulsation per unit time by the number of slots. The rotation speed No is calculated.

"Induced voltage measuring step" Next, in the "induced voltage measuring step", the personal computer 2 constituting the induced voltage measuring means is constructed.
(Specifically, the calculating unit 6 and the voltage measuring unit 7) and the switch 4
At, the application of the voltage to the DC motor M is stopped, and the induced voltage Eo at that time is measured.

More specifically, the switch 4 is turned off to stop the voltage application to the DC motor M. The voltage value (voltage value signal S3) input through the voltage measuring unit 7 at that time
Then, the calculation unit 6 measures the induced voltage Eo.

"Characteristic calculation step" Next, "Characteristic calculation step"
Then, in the calculation unit 6 which constitutes the characteristic calculation means, the constraint current Il, the no-load current Io, the no-load rotation speed N.
The constraint torque Tl is calculated based on o and the induced voltage Eo, and the characteristic (see FIG. 3) is specified.

More specifically, the calculation unit 6 calculates the no-load rotation speed N.
The angular velocity ωo at no load is calculated from o and the following formula (B), the angular velocity ωo, the induced voltage Eo, and the induced voltage constant Ek are calculated from the formula (C) below, and the characteristic (see FIG. 3) is calculated. Identify.

Ωo = 2π × No / 60 (rad / Sec) (B) Formula Ek = ωo / Eo (C) Formula Here, the induced voltage constant Ek is the current value-torque characteristic in the characteristic diagram shown in FIG. The current value-torque characteristic is specified from the fact that it is a value corresponding to the slope in and that the no-load current Io and the constraint current Il have already been obtained. Since the torque at the time of the restraint current Il is the restraint torque Tl, the restraint torque Tl is obtained from the current value-torque characteristic.
Is obtained. That is, the calculation unit 6 can calculate the constraint torque Tl from the constraint current Il, the no-load current Io, the induced voltage constant Ek, and the following equation (D).

Tl = (Il-Io) / Ek (D) Formula Further, as shown in FIG. 3, since the no-load rotational speed No is already obtained, the rotational speed-torque characteristic is specified. Therefore, the characteristic of the DC motor M (see FIG. 3) is specified.

Next, the output unit 8 outputs the calculation result, that is, the data of the characteristic (see FIG. 3) to an external monitor (not shown) and displays the characteristic on the monitor. Therefore, it is possible to specify the torque (rated torque, etc.) in an arbitrary state from the characteristics (see FIG. 3). Then, it is determined whether or not the characteristics and the value (rated torque, etc.) obtained by the characteristics satisfy the user's demand, and the product that is determined to satisfy the demand is set as a product.

Next, the characteristic effects of the above embodiment will be described below. (1) In particular, since the restraining current Il of the DC motor M is calculated from the inrush current It of the DC motor M and the predetermined constants α and β obtained in advance, load application for mechanically applying a load Characteristics (see FIG. 3) can be obtained by concentrated measurement (calculation) after assembly of motor parts without requiring equipment (electromagnetic brake, etc.) and torque sensor (torque-voltage converter, etc.). . As a result, with this method and apparatus, the characteristics can be easily obtained at low cost,
As a result, the DC motor can be easily manufactured at low cost. Also, when re-measurement of characteristics, disassembly /
The characteristics can be easily obtained at low cost without reassembling or the like.

(2) The characteristic is measured (calculated) and the characteristic (see FIG. 3) is obtained by simply applying the voltage once and then stopping the application of the voltage. Can be obtained.

(3) Since the inrush current It and the restraint current Il are measured in advance from 30 direct current motors of the same type and the same type, and the predetermined constants α and β are obtained based on the both measured values,
It is possible to easily obtain highly reliable constants α and β, and to calculate the highly reliable constraint current Il.

(4) The no-load rotation speed No is set to the no-load current I
Since it is calculated from the current pulsation component of o, it is possible to obtain each characteristic at low cost without requiring a mechanical rotation sensor or the like.

The above embodiment may be modified as follows. In the above-described embodiment, the DC motor manufacturing apparatus and method (characteristic measuring apparatus and method) have been described. However, if there is a demand to measure the binding current Il of the DC motor after the motor parts are assembled, the above-mentioned method is used. It may be performed using a part of the method. For example, when it is desired to re-measure only the restraint current of the completed DC motor, the restraint current may be calculated by the same method (restraint current calculation method) as the above-mentioned method “restraint current measuring step”. By doing so, a load applying device (electromagnetic brake, etc.) for mechanically applying a load.
In addition, a torque sensor (torque-voltage converter, etc.) is not required, and disassembly / reassembly is not required, and a restrained current can be easily obtained at low cost.

The DC motor manufacturing apparatus of the above embodiment has the same functions (inrush current measuring means, constraint current calculating means, no-load current measuring means, no-load rotation speed measuring means, induced voltage measuring means, and characteristic calculation). Means), the device may be configured by another device. For example, instead of the personal computer 2, a DC motor manufacturing apparatus may be configured by using a personal computer that does not include the current measuring unit 5 and the voltage measuring unit 7 and an A / D converter connected to the personal computer. .

In the above-mentioned embodiment, the output unit 8 is connected to an external monitor (not shown) and the characteristic which is the calculation result is displayed on the monitor. However, information based on the calculation result is transmitted to the information transmission means other than the monitor. It may be transmitted to. For example, a pass / fail judgment lamp is connected to the output unit 8. Then, the calculation unit 6 determines whether or not the characteristics satisfy the preset user demand. That is, the output unit 8 transmits the determination result, which is the calculation result of the calculation unit 6, to the outside by lighting the pass / fail determination lamp. Even with this,
It is possible to obtain the same effect as that of the above-described embodiment. Further, if the pass / fail judgment lamp is displayed in this way, it becomes easy for the operator to judge the pass / fail,
It is possible to further improve the production efficiency of a DC motor in a factory or the like.

In the above embodiment, the DC motor M is previously set.
The inrush current It and the confining current Il were measured from 30 completed DC motors of the same type and the same type, and predetermined constants α and β were obtained based on the measured values.
The method of obtaining β may be changed. For example, the number of DC motors to be measured in advance may be changed to other than 30, for example, 40 or 50. Further, for example, predetermined constants α and β corresponding to the DC motor M of the present embodiment may be obtained by regression analysis from predetermined constants of various types (different sizes, etc.) of DC motors. .

In the above embodiment, the no-load rotation speed No.
Was calculated from the current pulsation component of the no-load current Io, but the no-load rotation speed No may be obtained by another method. For example, the unloaded rotation speed No may be measured by a mechanical rotation sensor. Even in this case, the same effects as the effects (1) to (3) of the above embodiment can be obtained.

In the above embodiment, all the values necessary for obtaining the characteristics were measured (calculated) in the flow of once applying the voltage and stopping the application of the voltage. If each step can be performed under the same conditions as in the above embodiment, the voltage may be applied or stopped between the steps.
If the steps can be performed under the same conditions as in the above embodiment, the order in which the steps are performed may be appropriately changed. Even in this case, the effect (1) of the above-described embodiment,
The same effects as (3) and (4) can be obtained.

Next, the technical ideas that can be understood from the above-described embodiment will be described below along with their effects. (A) Inrush current measurement step of starting by applying a voltage after assembling the motor parts and measuring the inrush current at the time of starting, and a constraint for calculating the constraint current by the inrush current and a predetermined constant number obtained in advance. A current calculation process and a no-load current measurement process that measures the no-load current when the rotation under no load is stable,
A no-load rotation speed measurement step for measuring the no-load rotation speed when the rotation under no load is stable, and an induced voltage measurement step for stopping the application of voltage and measuring the induced voltage at that stop,
A method of manufacturing a DC motor, comprising: a characteristic calculation step of calculating a constraint torque based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage to specify a characteristic. Even in this case, the same effects as the effects (1), (3), and (4) of the above-described embodiment can be obtained.

(B) After the motor parts have been assembled, a voltage is applied to the motor to start it, and the inrush current measuring means for measuring the inrush current at the time of starting, the inrush current, and a constant constant determined in advance generate a constraint current. Restraint current calculating means for calculating, no-load current measuring means for measuring no-load current when rotation is stable under no load, no-load measuring speed for no-load when rotation is stable under no load Rotation speed measurement means, induced voltage measurement means for stopping the application of voltage and measuring the induced voltage when the voltage is stopped, and the constraint current, the no-load current, the no-load rotation speed, and the constraint based on the induced voltage A DC motor manufacturing apparatus, comprising: a characteristic calculating unit that calculates a torque and specifies a characteristic. Even in this case, the same effects as the effects (1), (3), and (4) of the above-described embodiment can be obtained.

[0058]

As described in detail above, according to the inventions described in claims 1 and 2, it is possible to provide a method of calculating a restricted current which can easily obtain a restricted current of a DC motor at low cost. .

According to the invention described in claims 3 to 5,
It is possible to provide a method of manufacturing a DC motor, which can easily obtain the characteristics at low cost and can easily manufacture the DC motor at low cost.

According to the invention described in claims 6 to 8,
It is possible to provide a DC motor manufacturing apparatus that can easily obtain characteristics at low cost and can easily manufacture a DC motor at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining a DC motor manufacturing apparatus of the present embodiment.

FIG. 2 is a characteristic diagram for explaining a current value of a DC motor after voltage application.

FIG. 3 is a rotational speed / current value-torque characteristic diagram of a DC motor.

[Explanation of symbols]

1 ... Current sensor, 2 ... Personal computer, 4 ... Switch, 5 ... Current measurement unit, 6 ... Calculation unit, 7 ... Voltage measurement unit, It ... Inrush current, Io ... No load current, Il ... Restricted current, No ... None Load speed, T1 ... Restraint torque.

Continued front page    F term (reference) 2G016 BA04 BB01 BB02 BB07 BC05                       BD05 BD06 BD09 BD16 BE03                 5H571 BB10 CC02 FF01 FF06 JJ03                       JJ16 KK06 LL22                 5H623 AA09 AA10

Claims (8)

[Claims] 1. A method of calculating a restricted current of a DC motor, comprising calculating a restricted current of the DC motor based on a rush current of the DC motor and a predetermined constant determined in advance. 2. The method for calculating a restricted current of a DC motor according to claim 1, wherein the predetermined constant is obtained by measuring an inrush current and a restricted current from a plurality of DC motors of the same type and the same type, and based on the both measured values. A method of calculating a restricted current of a DC motor, comprising: 3. An inrush current measuring step of measuring the inrush current at the time of starting by applying a voltage after assembling the motor parts, and calculating a restraining current by the inrush current and a predetermined constant determined in advance. After the inrush current measuring step, a no-load current measuring step of measuring a no-load current when the rotation under no load is stable, and a no-load current measuring step after the inrush current measuring step. No-load rotation speed measurement step of measuring the no-load rotation speed when the rotation is stable, after the no-load current measurement step and the no-load rotation speed measurement step, stop the application of voltage, induction at the time of the stop An induced voltage measurement step of measuring a voltage, and a characteristic calculation step of calculating a constraint torque based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage to specify a characteristic are provided. Characterized by Manufacturing method of the motor. 4. The method of manufacturing a DC motor according to claim 3, wherein the predetermined constant is obtained based on a measured inrush current and a restricted current from a plurality of DC motors of the same type and the same type. A method for manufacturing a DC motor, characterized by: 5. The method for manufacturing a DC motor according to claim 3, wherein the no-load rotation speed measuring step calculates a no-load rotation speed from a current ripple component of the no-load current. DC motor manufacturing method. 6. An inrush current measuring means for starting a voltage by applying a voltage after assembling the motor parts and measuring the inrush current at the time of starting, and a constraint current calculated by the inrush current and a predetermined constant determined in advance. Restraint current calculating means to, after measuring the inrush current, no-load current measuring means for measuring the no-load current when the rotation at no load is stable, and after measuring the inrush current, no load No-load rotation speed measuring means for measuring the no-load rotation speed when the rotation is stable, after measuring the no-load current and the no-load rotation speed, stop the application of voltage, the induced voltage at the time of the stop An induced voltage measuring unit for measuring, and a characteristic calculating unit for specifying a characteristic by calculating a constraint torque based on the constraint current, the no-load current, the no-load rotation speed, and the induced voltage. Direct current motor Manufacturing equipment. 7. The DC motor manufacturing apparatus according to claim 6, wherein the predetermined constant is obtained based on a measured inrush current and a restricted current from a plurality of DC motors of the same type and same type. An apparatus for manufacturing a DC motor, which is characterized in that 8. The DC motor manufacturing apparatus according to claim 6, wherein the no-load rotation speed measuring means calculates a no-load rotation speed from a current pulsation component of the no-load current. DC motor manufacturing equipment.