JPH0323662Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention relates to a fastener for reinforcing connection parts of electronic parts, etc., and in particular, a fastener for reinforcing cylindrical reinforcement fasteners made of a NiTi-based shape memory alloy to facilitate installation at low temperatures. The opening amount of the fastener slit is ensured.

[Conventional technology]

In recent years, connections between high-density fine pattern electrodes such as LCDs, LEDs, and ELs and flexible printed circuits have been
Chemical connectors such as anisotropic conductive films and elastomer connectors have come into use. This connection method improves reliability at low temperatures compared to conventional fixing methods, and allows equipment to be made smaller and thinner. However, this method has the disadvantage of poor reliability in high temperature ranges, and to improve this, the connection parts are hardened with resin or tightened with metal fittings, but those hardened with resin cause volume deformation depending on the environmental temperature. Therefore, the contact resistance at high temperatures fluctuates, and those that are fastened with metal fittings require a considerable amount of space, making it difficult to reduce the thickness.

In view of this, the inventors of the present invention proposed a method of covering the joint with a cylindrical fastener made of a NiTi-based shape memory alloy and having slits formed in the axial direction, and sandwiching the joint between the slits by restoring the shape of the fastener. For example, as shown in FIG. 3, an electrode glass substrate 2 of a liquid crystal 1 forming a high-density fine pattern electrode
A flexible printed circuit 4 is superimposed thereon via a chemical connector, for example, an anisotropic conductive film 3,
Electrical connections are made by heat fusion. to this connection
A cylindrical reinforcing fastener 5 made of a NiTi-based shape memory alloy and having slits 6 formed in the axial direction is placed on top, and the connection portion is sandwiched between the slits 6 as the fastener 5 recovers its shape for reinforcement.

[Problems that the invention aims to solve] NiTi-based shape memory alloys are alloys mainly composed of the intermetallic compound NiTi, or alloys in which Ni and Ti are partially replaced with other elements, and undergo martensitic transformation at around room temperature. When a certain shape is memorized at a temperature above the transformation point, even if it is deformed at a temperature below the transformation point, it returns to the memorized shape simply by heating above the transformation point. It is also known that it exhibits a superelastic effect at temperatures above its transformation point. The shape recovery temperature varies depending on the alloy composition, processing conditions, and shape memory treatment.

Therefore, a reinforcing fastener with zero slit opening is used, which has a shape recovery temperature of room temperature or lower than room temperature, has a slit formed in the axial direction, and is subjected to shape memory treatment to suppress the opening of the slit. Therefore, in order to attach the slit to a connector connection portion, etc., it is necessary to open the slit at a low temperature and maintain the temperature at that temperature until attachment, but this has the drawback that opening the slit requires a lot of work.

[Means for solving problems]

In view of this, as a result of various studies, the present invention has developed a fastener for reinforcing joints that makes it easy to open the reinforcing fastener made of a NiTi shape memory alloy. A slit opening for covering the connection part with the fastener at low temperature in a fastener in which a provided cylindrical fastener is placed over the connector connection part at low temperature, and the connection part is sandwiched between the slits and reinforced by the shape recovery of the fastener by heating. This is characterized in that a spacer to ensure the amount of opening is inserted between the slits in advance and combined.

That is, as shown in FIG. 1, the present invention is a cylindrical fastener 5 made of a NiTi-based shape memory alloy with slits 6 formed in the axial direction, in a state where the opening of the slit 6 is suppressed at a temperature above the martensitic transformation point. Shape memory treatment is performed, and after that, a spacer 7 is inserted into the slit 6, preferably at a temperature below the martensitic transformation point, to ensure an opening amount for fitting the fastener 5 over the connection part, etc. (not shown in the figure). It is.

The cross-sectional shape of the cylindrical fastener may be circular, oval, horseshoe, or the like.

[Effect]

A fastener made of NiTi-based shape memory alloy recovers its shape near room temperature and shows the memorized slit spacing. Even when it is cooled, the slit spacing does not open, but when external force is applied, it opens and connects the connector. It becomes easy to attach it to the parts, etc. Moreover, if the shape is restored while being placed over the connection part, the connection part is held between the slits. Therefore, after shape memory treatment, by using the superelasticity of the fastener or by opening the opening at low temperature and inserting a spacer into the slit part to ensure the opening amount to cover the connection part, it is possible to attach the connector to the connector connection part. This makes it easy to install.

That is, since the fastener for reinforcing the connection portion according to the present invention pinches the spacer by recovering its shape at room temperature, the spacer does not fall off from the slit portion. When installing, the fastener is cooled and the plastic spacer, which has been inserted into the slit in advance, is removed.At this time, the opening is opened by the thickness of the spacer, so the fastener is cooled and removed before the temperature rises and the shape recovers. The opening part is placed over the electrical connection part at a low temperature, the fastener is allowed to recover its shape by natural temperature rise or heating, and is then held between the slits and the connection part.

〔Example〕

NiTi alloy strip (Ni50at) with plate thickness 0.3mm and plate width 9.5mm
%, Ti50at%) into a tube with a diameter of 3 mm by roll forming, fixed on a jig so that the interval between butts is 0, and then subjected to shape memory treatment to form slits in the axial direction. I created a fuasuna for. Next, this fastener was cooled to a temperature at which it could be easily deformed (-30°C), and a spacer with a width of 7 mm, a thickness of 1.5 mm, and a length of 220 mm was inserted into the slit part of the fastener while sliding it in the longitudinal direction. A fastener for reinforcing the connection portion shown in the figure was obtained.

Next, to attach the fastener, the spacer 7 is inserted between the slits 6 as shown in FIG.
is inserted into the concave groove on the cooling guide plate 8 attached to the cooler 9, the fastener 5 is cooled to -30°C, and the spacer 7 is pulled out in the longitudinal direction and removed. At this time, the opening is opened by the thickness of the spacer, so before the temperature rises and the shape recovers, the fastener 5 is placed over the electrical connection part as shown in FIG. 5 was restored to its shape and the connecting portion was sandwiched between the slits 6. As a result, it was extremely easy to attach the fastener, and there was no change in the contact state of the connection portion, indicating that good reinforcement was achieved.

Although the slit portion of the fastener is slightly deformed when the spacer is retracted, if it is held as it is, the shape will recover as the temperature rises and it will return to the memorized shape.

[Effect of idea]

According to the present invention, when manufacturing a NiTi-based shape memory alloy fastener for reinforcing the connection of electronic components, etc., by installing a spacer in advance to ensure a desired opening between the slits, the opening when the fastener is installed is improved. Since there is no need for an opening operation and no need to apply an external force to open the mouth, it is extremely easy to install the fastener, and the connection part can be stably reinforced without damaging the slit surface that holds the connection part. It has remarkable industrial effects, such as the ability to

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the fastener of the present invention;
FIG. 2 is an explanatory view showing an example of removing a spacer from the fastener of the present invention, and FIG. 3 is a perspective view showing an example of reinforcing the connection portion by the fastener. 1...Liquid crystal, 2...Substrate, 3...Conductive film, 4...
... Printed circuit, 5 ... Fastener, 6 ... Slit, 7 ... Spacer, 8 ... Cooling guide plate, 9 ... Cooling device, 10 ... Control unit, 11 ... Power cord.

Claims (1)

[Scope of utility model registration request] A fastener in which a cylindrical fastener made of a NiTi-based shape memory alloy with slits in the axial direction is placed over a connector connection part at low temperature, and the connection part is sandwiched between the slits and reinforced by the shape recovery of the fastener by heating. A fastener for reinforcing a connecting part, characterized in that a spacer is inserted between the slits in advance to secure the slit opening amount for covering the fastener over the connecting part at low temperatures.