JPH01252156A - Braking gear for linear dc motor - Google Patents

Abstract

PURPOSE:To decrease the number of parts, and to reduce space in the lateral direction by oppositely installing a fixed and movable sections of a brake core at a predetermined interval while operating a permanent magnet and a back core for a linear DC motor for a brake gear in combination. CONSTITUTION:In normal operation, a coil 10c is excited by turning a power supply ON, an attracting force f1 produced by a coil 10c and acting on a moving core 10b becomes larger than another attracting force f2 produced by the magnetic flux of a permanent magnet 6, a gap g1 is formed between the moving core 10b and a back core 7, and a linear DC motor is operated in a specified manner. When an unexpected situation of service interruption is generated in such normal operation, the excitation of the coil 10c is stopped, and the attracting force f2 only due to the permanent magnet 6 acts on the moving core 10b, thus bringing the gap g1 to zero and attracting a brake core 10a to the back core 7, then applying an emergency brake to a motor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an emergency brake device used for linear DC motors mainly for factory automation, such as industrial robots.

[Prior Art] As shown in FIGS. 4 and 5, a conventional brake device for this type of linear DC motor has a non-excitation type brake device 2 in the width direction perpendicular to the running direction of the linear DC motor 1. It was configured in such a way that it was arranged. Although the details are omitted in the figure, the brake device is equipped with a dedicated permanent magnet and a mover, and when the mover is not energized due to power outage etc., it comes into close contact with the skewer plate 3 and acts as a brake, while during normal operation 2. During excitation, the gap g was widened and released as shown in the figure.

Note that 4, 5, 6, and 7 are the motor plate, stator, permanent magnet, and back core of the linear DC motor, respectively. Further, 8 is a back plate, and 9 is a linear bearing.

[Problems to be solved by the invention] Since the conventional brake device used a dedicated non-excitation type brake device, this configuration was required, and in order to install the brake device, a linear DC motor was required. There is also a drawback that space is required to provide the friction plates of the brake device along the entire stroke length in the width direction orthogonal to the running direction.

Means for Solving Problem E] The present invention uses a permanent magnet for the field of a linear DC motor as a non-excitation type brake device, and also uses a back core as a friction plate. The present invention relates to a brake device for a linear DC motor that eliminates the above-mentioned problems by dividing the brake device into a fixed part and a movable part.

[Example] An example of the present invention shown in FIGS. 1 to 3 will be described below. In the figure, structures corresponding to the conventional ones are designated by the same reference numerals as in FIGS. 4 and 5. 1
Liao is a brake device of the present invention in which a brake core is prepared separately into a fixed part 10a of the brake core having an E-shaped cross section and a movable part 10b of the brake core having a U-shaped cross section. If 10a is the length of the linear DC motor in the traveling direction as shown in the figure, then Lb, which is the same width as this, is the length (Lb).
L,>L,) and are placed side by side on the stator core 5a. Further, the movable part 10b of the brake core is disposed opposite to the fixed part 10a of the brake core with a gap g apart, and its central part S is opposed to the permanent magnet 6 with a gap g2 in the same way as the stator core 5a. Both ends T are configured to face the back core 7 with a gap g+ in between.

In this case, the relationship between each gap is.

They are arranged so that g2≧gs>gl. 10c is an excitation coil. In addition, in FIGS. 1 and 2, the brake core 10a is shown with hatching for convenience of explanation.

Further, FIG. 3 is a perspective view showing only the structure of the brake device 10 in order to explain the present invention in detail.

[Effect] Next, the operation of the present invention will be explained mainly with reference to FIG.

During normal operation, the coil 10c is excited when a power source (not shown) is turned on, and the attractive force f acting on the movable core 10b based on the magnetic flux generated by this coil is applied to the permanent magnet 5.
The attraction force based on the magnetic flux is larger than 2 (fl>fz),
, this attraction force f.

As a result, a gap g1 is created between the back core 7 and the brake, and the brake is in a released state, and the linear DC motor is operating in a predetermined manner.

When an unexpected situation such as a power outage occurs during normal operation, the excitation of the coil 10C is cut off and the attractive force f2 of only the permanent magnet 6 acts on the movable core 10b, so the gap g1 is reduced to zero and the brake core 10a is It is attracted to the back core 7 and an emergency brake is applied on the motor.

In addition, in the event of an unexpected situation other than a power outage, a sensor is provided to detect this emergency, and by turning off the power in conjunction with the operation of this sensor, the emergency brake is applied in the same way as above.

[Effects of the Invention] As described above, the present invention replaces the non-excitation type brake device that is provided in the width direction perpendicular to the direction of movement of the conventional linear DC motor.

A brake core equipped with an excitation coil is disposed in parallel with the stator core of the motor in the direction of movement, and the fixed part and movable part of the brake core are installed facing each other at a predetermined distance, and the permanent magnets and battery of the linear DC motor are , the core is configured so that it can also be used as a brake device.

Therefore, it has the following superior effects compared to the conventional one.

■The number of parts can be reduced because the permanent magnets and brake friction plates required in conventional models can be omitted.

■Since it is now possible to omit the brake friction plates that were conventionally provided across the entire length of the stroke at positions in the width direction perpendicular to the direction of travel, the space in the width direction of the equipment can be reduced accordingly.

■As a result, the entire device can be made small and inexpensive.

■Since the brake core is divided into a fixed part and a movable part, it is now possible to easily create the related parts for moving the movable part.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention, in which Figure 1 is a plan view, Figure 2 is a sectional view taken along line AA' in Figure 1, and Figure 3 is a perspective view. be. In addition, FIGS. 4 and 5 each show conventional examples,
FIG. 4 is a plan view, and FIG. 5 is a sectional view taken along the line AA° in FIG. 4. Engineering---Linear DC motor 1 pulling-m-Brake device 10a--Fixed part 10b of brake core--Movable part 10c of brake core--Coil 61--Permanent magnet 7--Back core applicant God *1 Representative of Ki Co., Ltd. Patent attorney Haruya Saito and 2 others 1. Rishii LIL Mikui Mo, Ri

Claims (1)

[Claims] 1. In a linear DC motor having field permanent magnets arranged in a straight line, a fixed part of the brake core with an excitation coil placed side by side in the direction of movement of the stator core is separated from this fixed part by a predetermined distance. The permanent magnet of the linear DC motor and the movable part of the back core are used for braking, and the attraction force based on the magnetic flux of the permanent magnet causes the brake core to move. The moving part is attracted to the back core to activate the emergency brake, while during normal operation when a power source is present, the attraction force based on the excitation of the brake coil cancels out the attraction force of the permanent magnet, and the movable part of the brake core A brake device for a linear DC motor, characterized in that a gap is formed between back cores to release the brake.