JPH0363308B2 - - Google Patents

Description

[Detailed description of the invention] "Technical field" The present invention relates to a linear pulse motor.

"Prior Art and its Problems" Conventionally, for example, the carriage feeding mechanism of printers and magnetic disk devices in OA-related equipment has been designed to control the rotation of the drive motor using gears and racks, pulleys and steel belts, or lead screws. A mechanism has been adopted in which the carriage is moved in a straight line using this linear motion. However, the motion conversion mechanism of this device is large and complicated, which hinders the miniaturization and cost reduction of the entire device.Furthermore, the wear and deterioration of the power transmission system parts progresses, causing problems with the carriage. There was also a problem with accuracy, which made positioning difficult.

Therefore, from this background, we have already developed an indirect power transmission mechanism using a conventional motion conversion mechanism.
A linear pulse motor that can directly move a carriage linearly is employed, and a mechanism is employed in which the mover of this linear pulse motor is used directly as a carriage.

FIG. 6 is an external view of this carriage moving mechanism using a linear pulse motor.A flat stator 10 has stator teeth 11 created at a constant pitch in the center, and running rails 12 are formed on the left and right sides. .
The movable element 20 has wheels 22 that are rotatable around an axis 21 and run on the traveling rail 12, and further includes:
A permanent magnet and an electromagnet 23 facing the traveling rail 12 and having teeth of a different pitch are mounted.

In the linear pulse motor described above, when a driving pulse is applied to the electromagnet 23 of the movable element 20, the wheels 22 of the movable element 20 move linearly in steps while rolling on the running rail 12 according to the well-known operating principle of a linear pulse motor. do. Therefore, it is possible to fix a magnetic head, a thermal head, etc. to the movable element 20 and use it as a carriage.

In this linear pulse motor, when the movable element 20 moves horizontally, the stop position does not deviate due to a difference in the moving direction. However, mover 20
If the direction of movement is inclined or vertical,
In principle, the stator 10 and the mover 20 are simply attracted to each other by the magnetic force of the permanent magnet, so the stopping position may be deviated depending on the direction of travel due to the influence of the weight of the mover 20. There was a problem. In FIG. 7, the mover 20 is arranged to move in the vertical direction, and is moved in the α direction and β direction in FIG.
Mover 20 when moved in the direction (up and down)
This is a graph showing actual measurements of changes in the stopping position of the vehicle.

``Object of the Invention'' In view of this problem of conventional linear pulse motors, the present invention provides a device that does not cause deviations in stop position accuracy due to the moving direction even if the stator (movable element) is installed in an inclined or vertical direction. The purpose is to obtain.

"Summary of the Invention" The present invention was made based on the idea of solving the above problems by using a balance weight that has approximately the same weight as the movable element. A pair of pulleys are disposed at the center, and a substantially endless belt is stretched between the pair of pulleys, and a movable element and a movable belt are disposed on each side of the belt in different running directions. It is characterized by a fixed balance weight that is approximately equal to the weight of the child.

"Embodiments of the Invention" The present invention will be described below with reference to illustrated embodiments. In FIGS. 1 to 4, a stator 10 and a movable element 20 are the same components as in the conventional device, and other same components are also given the same reference numerals. On the stator 10 , pulleys 14 , 14 are supported which are located on both ends of the movable element 20 in the moving direction and are rotatable about a shaft 13 . 15 is a locking word to prevent it from coming off. A substantially endless steel belt 17 including a balance weight 16 is wound between the pair of pulleys 14, 14. That is, both ends of the steel belt 17 wound around the pulleys 14, 14 are fixed to both ends of a balance weight 16 by fixing screws 18, and this balance weight 16 also serves as a part of the endless belt 17. Of course steel belt 1
7 is made into an endless shape, and a balance weight 1 is attached to it.
6 may be fixed.

The annular steel belt 17 has the movable element 20 attached to the fixing screw 24 on the side where the running direction is different from the side on which the balance weight 16 is fixed.
When the mover 20 moves in either direction α or β, the balance weight 16 moves in the opposite direction. The weight of the balance weight 16 is set equal to the weight of the mover 20.

Note that the wheels 22 of the mover 20 are connected to the running rail 12.
It has a flange 25 located inside. This flange 25 is always pressed into contact with the traveling rail 12 by a compression spring 26 fitted on the outer periphery of the shaft 21 between the wheel 22 and the mover 20, and the mover 20 is moved in a direction orthogonal to the α and β directions. Regulations are in place to prevent this from occurring.

This linear pulse motor with the above configuration has two electromagnets.
When no current is flowing through the magnet 3, the stator 10 and the movable element 20 are simply attracted to each other by the magnetic force of the permanent magnet, and the movable element 20 does not move. When a driving pulse is applied to the electromagnet 23, the movable element 20 moves stepwise in the α direction or the β direction based on the operating principle of a linear pulse motor. Then, the balance weight 16 connected to the movable element 20 by the steel belt 17 moves in the opposite direction to the movable element 20.

According to this device, the accuracy of the stop position of the movable element 20 can be improved regardless of whether the movable element 20 moves horizontally, vertically, or along an inclined surface. First, mover 20
It is clear that when moving in the horizontal direction, the weight of the movable element 20 and the balance weight 16 does not affect the accuracy of the stopping position, as in the conventional device. On the other hand, when the moving direction of the mover 20 is inclined or facing the vertical direction, the weight of the weight balance weight 16 of the mover 20 is set equal to that of the mover 20.
The influence of the weight of the movable element 20 does not affect the stopping accuracy. That is, regardless of whether the mover 20 moves in the α direction or the β direction, the balance weight 1
6 eliminates the influence of the weight of the movable element 20, so the movable element 20 can be stopped with exactly the same precision as when moving the movable element 20 horizontally.

FIG. 5 is a graph showing actual measured stopping positions when the apparatus shown in FIGS. 1 to 4 is arranged vertically and the movable element 20 is actually moved in the α direction and the β direction.
Comparing this graph with the graph of the conventional device shown in FIG. 7, it is clear that in the device of the present invention, the moving direction of the movable element 20 does not affect the stopping position accuracy.

"Effects of the Invention" As described above, the linear pulse motor of the present invention has
Even when the moving direction of the movable element is other than horizontal, the stop position accuracy will not be affected by the difference in the moving direction, so it can be used as a feeding mechanism for OA equipment, etc. without being subject to restrictions on the installation direction. This not only increases the degree of freedom in design and industrial design, but also has the effect that the OA equipment does not necessarily need to be placed horizontally, allowing for rough placement.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the linear pulse motor of the present invention, and FIGS. 2, 3, and 4 are
1 and an arrow view, respectively, and FIG. 5 is a graph showing the actual measurement of the stopping position by the device of the present invention.
FIG. 6 is a perspective view of a conventional linear pulse motor, and FIG. 7 is a graph showing actual measured stop positions in the conventional device shown in FIG. 10... Stator, 11... Stator tooth, 12...
Running rail, 14...pulley, 16...balance weight, 17...steel belt, 20...mover, 22...wheel, 23...electromagnet.

Claims (1)

[Claims] 1. In a linear pulse motor in which a movable element is supported so as to be linearly movable on a flat plate-shaped stator and the movable element is moved in steps by driving pulses applied to an electromagnet, the movable element is supported on the stator at both ends of the moving range of the movable element. A pair of pulleys are disposed at the same position, and a substantially endless belt is stretched between the pair of pulleys. A linear pulse motor characterized in that a balance weight having a weight approximately equal to the weight of the child is fixed.