JPH0545105Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a linear motor, and more specifically, in a linear motor that conveys a load in the vertical direction, that is, in the vertical direction, when moving the movable part, The present invention relates to a linear motor configured such that the influence of the mass of the parts can be almost ignored.

[Prior Art] Linear motors can be roughly classified according to the type of thrust: linear direct current motors (LDM), linear induction motors (LIM), and linear pulse motors (LPM).
The main products are linear vibration actuators, linear synchronous motors, MHD pumps, etc.

Regarding the direction of thrust, in most cases the load is conveyed vertically, but in some cases it is moved up and down along an inclined surface.Also, as the applications of linear motors are expanding, the load is conveyed vertically. It is also increasingly being used for transportation.

In this way, when using a linear motor to move a load in the vertical direction, the force in the direction of gravity, which is the weight L of the load plus the linear motor's own weight M, must be constantly supported for transportation. It is necessary to apply a thrust of

In this way, if the required thrust increases, not only the structure of the linear motor itself for generating the thrust but also the size of related parts will increase, which increases the manufacturing cost and power consumption of the linear motor transfer device as a whole. It is inevitable.

As a measure to prevent increases in manufacturing costs and power consumption, as shown in FIG.
The pulley 1 is mounted on top of the
A method is adopted in which the motor is balanced with the linear motor 10 via the motor 6 or the like.

[Problem to be solved by the invention] In the above method, the weight of the linear motor is balanced, but the movable part 10 of the linear motor and the counterweight 10', which has almost the same mass, are connected by wire etc. and have the same inertia. Since it belongs to the system,
The mass of the linear motor 10 is approximately twice the mass M of the linear motor 10, which increases the inertia of the movable part. The structure of will inevitably become larger.

[Means for solving the problem] In solving the above-mentioned problem, the main goal is to minimize the increase in inertia without significantly increasing the space of the entire transport device. did.

A solution that meets this goal is to apply a tension in the direction opposite to gravity to the moving part of a linear motor that moves up and down, enough to cancel out the mass of the moving part or reduce it to a negligible value. As a specific tensioning means, the free end of a constant tension spring is connected to the movable part of the linear motor, and the fixed core part of the constant tension spring is always above the movable part on the fixed part of the linear motor. For example, it is set at an appropriate position on the upper surface of the fixing part.

[Operation] A constant tension spring has a constant tension spring, regardless of the length of the spring component such as a leaf spring drawn out from a fixed core.
Since the linear motor is constructed so that a constant tension is always applied to the point of application, the weight of the moving part of the linear motor is kept canceled by the constant tension spring, regardless of its position on the fixed part. The effects of inertia can be kept to a minimum.

This is similar to when a human body is submerged in water, and the buoyancy provided by the water makes the human body almost weightless.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic side view showing one embodiment of the present invention, showing a roller for maintaining a constant distance from a fixed part. Reference numeral 10 is the moving part of the linear motor,
A roller 15 is provided on the side surface that contacts the fixed part to maintain a constant distance from the fixed part.

11 is the secondary side of the linear motor, that is, the fixed part, which is a permanent magnet and iron in a linear DC motor (LDM), aluminum and iron in a linear induction motor (LIM), and a comb called a scale in a linear pulse motor (LPM). Consists of tooth-shaped magnetic material.

Reference numeral 12 denotes a fixed tension take-up spring consisting of a fixed core 14 and a spring material 13 such as a spiral spring wound around the fixed core 14. The fixed core 14 is attached to the secondary side of the linear motor, that is, the upper surface of the fixed part 11, The tip portion drawn out from the fixed core 14 is connected to the movable portion 10 of a linear motor.

The mass of the load to be transported is almost constant,
When the load is used in a state where the load is conveyed to the movable part 10 while maintaining a substantially constant value, the tension of the constant tension take-up spring may be set to include the mass of the load. .

[Effects] Since such a fixed tension winding spring generally has a simple structure, its two masses can be extremely light compared to the moving part of a linear motor, and the winding that is unwound from the fixed core 14 can be Regardless of the length of the take-up spring, that is, the position of the movable part 10 on the fixed part 11, it is possible to balance the movable part 10 by applying an upward traction force in the opposite direction to the gravitational field, so the thrust force is extremely small. This makes it possible to transport loads.

The constant tension take-up spring can be installed on the top surface of the fixed part 11, and there is no need to arrange a balance weight or the like on the side of the fixed part 11 opposite to the movable part 10, so the entire conveying device can be made smaller. It is also effective for reducing the size and weight.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing a preferred embodiment of the present invention, and FIG. 2 is a schematic side view of a conventional linear motor conveyance device employing a counterweight system. Reference numerals in the drawings: 10...Movable part of linear motor, 11...Fixed part of linear motor, 12...Constant tension take-up spring, 12'...Free end of take-up spring, 13...Spring material, 14 ...Fixed core,
15... Laura.

Claims (1)

[Scope of utility model registration request] A vertical linear motor conveying device that moves vertically to convey a load, comprising a movable part and a constant tension winding spring connected to the movable part and applying tension to the movable part in the opposite direction to the gravitational field sufficient to offset the mass of the movable part or reduce it to a negligible value.