JPH071729B2 - Temperature-sensitive actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a temperature-sensitive actuator that operates at a certain operating temperature to achieve a desired object, and more specifically, for example, a coating line for automobiles. The present invention relates to a temperature-sensitive actuator which is effectively used in the baking process.

(Prior Art) For example, in an automobile painting line, when spray painting, a large number of water drain holes formed on the lower surface of the body are sealed. This is to prevent the sprayed paint from clogging the drain holes. After this sealing, spray coating is carried out, then transferred to a baking process and the paint is baked at a temperature of 100 to 200 ° C. Prior to this baking work, the worker performs the plug removing work one by one.

(Problems to be Solved by the Invention) However, at present, the above-mentioned unplugging work is carried out manually by an operator who digs under the body. This is a labor-intensive work, and is also a complicated work that requires attention to the operator.

The present invention solves such a problem, and even when the body is heated to the baking temperature even if it is transferred to the baking process with the stopper tightly closed, the stopper is automatically removed from the drain hole and removed. An object is to provide a temperature-sensitive actuator that can be plugged.

[Structure of Invention] (Means / Action for Solving Problems) The present inventor, in the process of earnestly researching in order to achieve the above-mentioned object, is that the automobile body is made of an iron plate, That heat is applied to the stopper, and that each magnetic material has its own Curie point (Tc),
Based on the above idea, a temperature sensitive actuator of the present invention which operates at a predetermined temperature has been developed by combining these.

That is, the temperature-sensitive actuator of the present invention can generate a ferromagnetic material having a Tc higher than the operating temperature by 0 to 50 ° C. and a magnetic force capable of magnetizing the ferromagnetic material, and has a Tc higher than that of the ferromagnetic material. It is characterized by being combined with a permanent magnet having.

The temperature-sensitive actuator of the present invention has Tc of 0 to 0 depending on the operating temperature.
It consists of a ferromagnetic material that is 50 ° C higher and a permanent magnet that has a higher Tc than this ferromagnetic material.

Here, the working temperature is, for example, in the case of the above baking line,
A temperature that is slightly lower than the baking temperature, that is, a temperature before the paint is baked and solidified, at which you want the stopper to come off,
In other words, it means the temperature at which the temperature sensitive actuator should operate. Since this temperature is the operating temperature at which the temperature sensitive actuator is operated, it cannot be unconditionally determined.

The ferromagnetic material and the permanent magnet used are not particularly limited, but the Tc of the ferromagnetic material is 0 to 50 ° C. higher than the operating temperature, and the Tc of the permanent magnet must be higher than the Tc of the ferromagnetic material. And preferably 200 ° C from the Tc of the ferromagnetic material.
The above Tc is preferable. This is because the Tc of the permanent magnet must be sufficiently higher than the operating temperature and the magnetic force must not be too small at the operating temperature. If the Tc of the ferromagnetic material is lower than the operating temperature, the temperature-sensitive actuator will operate below the operating temperature, which is not desirable. If it is higher than 50 ° C, the ferromagnetic material will remain magnetized even after the operating temperature is exceeded. Since the temperature sensitive actuator does not operate smoothly, the above range is set.

At this time, when the usage mode is the baking process as described above, the baking temperature is usually about 120 ° C., and the desired temperature of the stopper is about 80 to 100 ° C. A material having a Tc of about 90 to 130 ° C. may be selected, and a material having a higher Tc, eg, about 500 to 700 ° C. may be selected as the permanent magnet.

In the case of such a relatively low operating temperature, examples of ferromagnetic materials include magnetic shunt alloys such as Ni-Zn ferrite; Co-Ni amorphous alloys, Co-Si-B amorphous. Amorphous magnetic alloys such as quality alloys are suitable, and rare earth magnets such as Sm—Co magnets are suitable as permanent magnets. These ferromagnetic materials and permanent magnets may be used alone or in the form of a composite with a resin.

In the temperature-sensitive actuator of the present invention, the above-mentioned ferromagnetic material and permanent magnet are bonded by a heat-resistant adhesive such as a silicone rubber adhesive, or mechanically integrated by using a means such as a bolt-nut. Composed and combined. If necessary, it may be coated with a fluororesin or the like.

A mode of an example in which the temperature-sensitive actuator of the present invention is used as the plug of the above-mentioned coating line will be described in more detail with reference to the drawings. In the figure, 1 is an iron plate on the lower surface of the body, and 2 is a drain hole. Reference numeral 3 denotes a ferromagnetic material having a stepped structure at its peripheral edge as shown in the figure. The central projection 3a closes the drainage hole 2, and the stepped portion 3b abuts the lower surface of the body 1. Four
Is a permanent magnet integrally combined with a ferromagnetic material.

First, at room temperature, the ferromagnetic body is magnetized by the permanent magnet, and the whole body is attracted to the lower surface of the body through the step portion 3b. That is, the sealed state is achieved.

After that, when the body is transferred to the baking process and the stopper is heated to a temperature around Tc of the ferromagnetic body, the ferromagnetic body loses its magnetism. As a result, the suction force with the body is reduced, and the plug body is unplugged from the drain hole by its own weight.

(Examples of the invention) A Co-Si-B amorphous alloy (Tc: 115 ° C) was selected as the ferromagnetic material, and a 2-17 series Sm-Co permanent magnet (Tc: 850 ° C) was selected as the permanent magnet. The ferromagnetic material was processed to form a protrusion having a diameter of 30 mm and a height of 3 mm and a step portion having a width of 3 mm and a thickness of 15 mm in the center. A disk with a diameter of 30 mm and a thickness of 2 mm was machined from the permanent magnet. Both were bonded with a silicone rubber adhesive (heat resistance of 180 ° C.) and coated with Teflon to obtain a plug.

This plug was inserted into the water drain hole of the car body. The plug was adsorbed to the body and the water drain hole was sealed.

Then, after spraying a predetermined amount on the upper surface of the body, the whole body was transferred to a baking process at 120 ° C. When the temperature of the body near the drainage hole increased to about 110 ° C, the plugs dropped one after another and were removed.

[Effects of the Invention] As is clear from the above description, the temperature-sensitive actuator of the present invention operates by itself without any input due to the loss or decrease of the magnetism of the ferromagnetic material at a certain operating temperature. For example, it is extremely useful when applied to a plug body that tightly plugs a drain hole in an automobile painting line.

[Brief description of drawings]

The figure is a schematic view showing a state in which the temperature-sensitive actuator of the present invention is applied as a stopper used in a coating line of an automobile. 1 ... Body, 2 ... Drainage hole 3 ... Ferromagnetic material, 3a ... Central protrusion 3b ... Step, 4 ... Permanent magnet

Claims (2)

[Claims] 1. A temperature sensitive actuator comprising a combination of a ferromagnetic material having a Curie temperature higher by 0 to 50 ° C. than an operating temperature and a permanent magnet having a Curie temperature higher than that of the ferromagnetic material. 2. The temperature sensitive actuator according to claim 1, wherein the Curie temperature of the permanent magnet is higher than the Curie temperature of the ferromagnetic body by 200 ° C. or more.