JPS5997857A - Tools consisting of shape memory metal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to tools made of so-called shape memory metals.

In shape-memory metals, the internal phase at high temperatures passes through a transformation region upon cooling; for example, a metal that forms a γ phase at high temperatures maintains a stable α phase at room temperature.When a metal is cooled, it transforms into martensite. The structure is changed to memorize the specific shape at that high temperature without undergoing complete in-phase transformation, and then an appropriate heat treatment is performed to form a deformed molded body, which is then cooled and maintained at room temperature. If it is processed and deformed into an appropriate shape at room temperature within a certain temperature range, and later heated and maintained at a certain temperature, it will return to the shape it had at the originally memorized high temperature. In addition to this, there are many phenomena of shape memory and restoration of metals, and compositions have been proposed that take advantage of the phenomenon of reincarburizing the shape under appropriate conditions.

Further, development is underway to utilize the restoration characteristics of this memorized shape in practical applications, such as springs, bimetals, switch contacts, hooks, and hooks.

Such metals include gold-cadmium, copper-zinc,
Nickel-aluminum, nickel-titanium, etc. are known. From these, at least one type is arbitrarily selected and used depending on the purpose of use.

The present invention provides these so-called shape memory metals whose material composition is TixNil-x, Ti) (Nio, o
Regarding items such as xOuo and x+Ou Zn AJ7, we effectively utilize their attributes to create accurate practical products.
The purpose is to provide practical tools. To achieve this object of the invention, a shape memorized metal is deformed at room temperature to give it the desired shape and then heated to a temperature suitable for decarburizing the memorized shape. In this case, "during room temperature deformation processing, restoration by heating to recarburize to the memorized shape, and subsequent cooling (this case is called unidirectional restoration)", and "during room temperature deformation processing and restoration to the memorized shape" At the time of heating restoration for restoration and subsequent cooling, followed by heating restoration shape and subsequent cooling (this case is called bidirectional restoration).

)” exists. For example, the example shown in FIG. 3 belongs to the former type, which is unidirectional, and the example shown in FIG. 4, for example, belongs to the latter type, which includes the unidirectional type.

When implementing the present invention, the most important implementation conditions in these cases will be determined, and the embodiment of the technical problem to achieve the purpose of the present invention will be clarified.

Next, one embodiment of the present invention will be explained based on the drawings. 1A, 1B and 10 are side sectional views of the bin set. Figures 2A, 2B and 20
The figure is a side sectional view of a scraping tool of another embodiment. Figures 3 and 4 are relationship diagrams between elongation (deformation amount) and temperature.

The bottle sets shown in FIGS. 1A, 1B, and 1C were made of T1Ni shape memory metal wire with a diameter of 0.05 m. Attach both left and right ends IN and I to tip 1 of the bottle set.
B is fixed to an abrasive material such as carbide, and a shape memory alloy is used for the extended portion 4. The two joints of the shape memory alloy and 2B are heated and deformed into a memorized shape and bent so that the tips IA and 1B match.

Three fixing members and 3B were fixed to the other fixed end 3 of the bin set. The two parts of alloy 4 and 2B are processed to memorize the shape shown in FIG. 1B, and after cooling, the shape shown in FIG.
It is used after being transformed into the shape shown in FIG. 1C. The configuration shown in FIG. 1B can be restored by heating the fixed ends 313A and 3B of FIG. 1C and heating the shape memory metal 4 to bend the two joints 2B to the memorized shape.

For example, insert a bottle set with the tip 1 extended in a straight line as shown in the IC diagram deep into the pore, set it so that it is holding the item you want to take out, and in that state, tighten the fixed end 3. It can be heated to restore the memorized shape as shown in Fig. 1B, and then be used to firmly grip and pull out an item at the bent tips IA and IB at the joints 2A and 2B (3). The claw member at the tip is made of carbide, so it won't wear out or slip.

Figures 2A to 20 show other embodiments, in which 11 is a scraping tool made of a shape memory alloy, the tip of which changes from 912 to 12B, or from 120 to 120, or from 120 to 12 when heated. . 11 people coated the tip with hard material.

11B and 110 are alms. 13A, 13B,
Each 130 is a pattern. When using this tool, insert the tool in the state shown in Fig. 2A with a straight tip of 12A,
heating the handle portion 13A and bending the tip into a memorized shape 120;
If you pull it out in the state shown in Figure 2C, the contents will be bent at the tip 1.
20 and can be taken out. In this case, when inserting the tool, the tip is inserted in the straight state 12A, so it can be easily inserted, and since it is pulled out in the bent state 120, the contents can be easily scraped off. 11 people covered the part where items are hung with carbide, IIB, 110
It is wear resistant because it is coated.

(4) Of course, when corrosion resistance is required for the covering material, a corrosion-resistant material can be used.

Figure 1A, Figure 1B, Figure 1C, Figure 2A, Figure 2B,
In one example shown in FIG. 2C, the shape is deformed depending on the purpose of the article, the usage conditions, the type of shape memory metal used and the conditions in the treatment process, and at room temperature. Important elements are determined in advance based on applicable empirical rules according to the conditions, so that appropriate effects can be achieved during use.

Among these, there are those shown in FIGS. 3 and 4 in terms of models that should be particularly noted.

FIG. 3 is an example of a unidirectional configuration. When the memory shape is model M2 shown in the figure, when Ml, which is deformed D shown in the figure at low temperature T1 (in this case deformed to 8% by the elongation coefficient), is heated to the shape recovery temperature T2 of T2) TI, Even if the temperature changes shown in A2 and A3 occur, model M2
The shape will be as shown in . At T2, the deformation is not the D deformation but the memorized shape. When this is further cooled, for example, by cooling along the C1 curve, the shape changes close to the shape before the D deformation, but it does not completely restore, and a certain strain as shown in d in the figure occurs. This distortion needs to be confirmed.

FIG. 4 is an example of a bidirectional one. When the memory shape is model N2 shown in the figure, when the deformation D1 shown in the figure is 8% elongated at low temperature T1, when heated to the temperature T2 which is T2) TI for restoration, it becomes A2 as shown in the figure. Even if there is a temperature change of A3, cooling will reduce the temperature to T3 (TI≦
When T3<T2), deformation appears along curve C1, and then when heated from temperature T3 to temperature T4 (T2t in T4 or T4 (T2), it deforms and becomes a memory shape close to model N2. However, the deformation occurs as shown by the hysteresis curve shown in Figure 4. Thus, the deformation, temperature, and hysteresis characteristics of these elements must be carefully confirmed.Compared to the unidirectional case shown in Figure 3, , distortion occurs quickly, and restoration to the memorized shape is not complete.These must be determined in advance as empirical rules.

In both cases of Fig. 3 and Fig. 4, the amount of restoration that can be reproduced even if the D deformation, in which the memory shape is deformed by low-temperature deformation, is added again to make the amount of deformation constant, and the same deformation is applied repeatedly. It is impossible for the shape to be the same, but it may cause distortion and may not be restored to the same shape as the original memory shape, so it is necessary to reliably determine the presence or absence of this phenomenon and the amount of distortion.

For example, in the case of NiTi metal, the unidirectional recovery amount is about 5 to 6 factors when deformed by 8 inches,
The temperature gradient when the D-deformed one deformed into the memorized shape was 0.3 to Q, 5 mx/°C. Since bidirectional reconstruction is extremely complex, it is necessary to check reproducibility on a case-by-case basis.

As already explained, the present invention makes use of the characteristics of shape memory metal to create a relationship diagram between temperature, amount of deformation, and amount of memory shape recovery when repeatedly reproducing the memory shape, for example, in a unidirectional manner. It is necessary to accurately determine the hysteresis curve, measure the degree of strain, and determine the temperature gradient.

In short, for one memory shape, shape memory (7) is determined by determining the metal, the amount of deformation, the amount of recovery, the heating temperature, and the temperature gradient, and performing the process under one determined condition with a certain amount of recovery of the memory shape. It can be used extremely effectively for tools such as tweezers. Since the required parts are coated or partially attached with wear-resistant or corrosion-resistant materials, it can be applied to any tool.

[Brief explanation of the drawing]

1A, 1B, and 1C are side sectional views of an embodiment of the present invention. FIGS. 2A, 2B, and 2C are partially enlarged side cross-sectional views of another embodiment of the present invention. FIG. 3 and FIG. 4 are relationship diagrams of the relationship between the amount of deformation, temperature, and amount of memory shape recovery, and the model. 1 End 1 person, IB Wear-resistant member 3 Fixed end 2A, 2B Joint deformation part 4 Shape memory metal ÷A72-B-hard-]fB-Tl, T2. T3
．． T4 Temperature D, d Deformation Ml, M2 Model Nl, N2. N3 model patent applicant
Representative of Inoue Japax Institute Co., Ltd. Patent attorney
Nakanishi - (9) -327- (8) Fig. 3 Rad unfilled θC Fig. 2B Fig. 2A Fig. 4 1 Geki-shi

Claims (1)

[Claims] 1 A shape memory metal of a predetermined composition memorizes a predetermined shape by processing from a high temperature, deforms it into an arbitrary shape at a low temperature, and is heated or cooled during use, or is used by repeating the process, and is used as a wear-resistant or corrosion-resistant material. Tools made of shape memory metal, characterized by being coated with or partially attached to a metal.