JPH0717039B2 - Buffer body and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a buffer that is attached to a precision instrument that requires heat resistance and cold resistance and that buffers vibrations and shocks even in a wide temperature range from low temperature to high temperature. Regarding the body

[Conventional technology]

As is well known, a cushioning body is attached to a required place in a precision device such as a CD player, a precision balance, and a measuring machine, whose function is easily damaged by vibration or shock. As such a buffer, a rubber material molded into a predetermined shape,
Some have silicone oil sealed in a container.
It has also been practiced to directly attach a silicone gel alone to a required portion of a precision instrument.

[Problems to be Solved by the Invention]

However, according to the above-mentioned conventional technique, the rubber material does not buffer minute vibrations and shocks, and the silicone oil enclosed in the container is complicated in structure of the container, and hence it takes time to manufacture, In addition, in order to attach silicone gel directly to precision equipment, the high adhesiveness of the silicone gel surface is unsuitable for handling, and in addition, the silicone gel alone has low mechanical strength such as tensile strength and strength against compressive load. There is a problem in that it cannot be attached to support a part of the device. Further, it may be considered that a buffer body is formed by combining a thermoplastic elastomer and a silicone gel or a thermoplastic resin and a silicone gel, but in this case, the heat resistance as the buffer body is poor, especially at a temperature of 100 ° C or higher. Its use is difficult in the area. Further, among the rubber materials, the crosslinked silicone rubber has different properties from the above-mentioned thermoplastic elastomer or thermoplastic resin and is difficult to be welded to each other, so that it is difficult to use it as a constituent member of the buffer body.

[Means for Solving the Problems]

This inventor has completed various aspects of the present invention as a result of various considerations in view of the above-mentioned drawbacks of the conventional cushioning body.
A sheet made of 80Hs silicone rubber with a bulge on one side, a silicone gel cured body with a penetration of 50 to 150 filled in the bulge, and a silicone rubber made of silicone rubber with a rubber hardness of 20 to 80Hs. A flat plate-like thin plate which is joined to the other side of the sheet via an adhesive layer made of rubber and encloses the silicone gel cured body between the sheet and a surface of the thin plate opposite to the joining surface with the sheet. And a flat portion substantially parallel to the thin plate on the surface of the bulging portion of the sheet, and a hollow bulging portion on one side of the sheet made of silicone rubber. After opening a sheet on the other side of the sheet to form a plurality of sheets, the hollow portion of the bulging portion is filled with liquid silicone gel, and the liquid silicone gel is cured to obtain a cured silicone gel product having a penetration of 50 to 150. And provided separately A plurality of thin sheets made of silicone rubber are coated with an adhesive material, and the other side of the thin sheet is adhered to the other side of the sheet with liquid silicone rubber so as to seal the silicone gel cured body. The purpose is to form a jacket, and then cut and separate each jacket to manufacture a cushioning body.

[Action]

According to the above-mentioned means, the hollow bulging portion of the sheet made of silicone rubber is filled with the liquid silicone gel, and then the liquid silicone gel is cured to have a penetration of 50 to 150.
The thin plate made of silicone rubber, which is a cured body of silicone gel, is firmly adhered and integrated with the liquid silicone rubber on the sheet to form a sealed envelope body. A buffer filled with a gel hardened body can be easily obtained. In addition, this buffer
It has an outer jacket made of silicone rubber with excellent heat and cold resistance, and has improved mechanical strength such as tensile strength and strength against compressive load compared to the case of silicone gel alone, and the adhesion of the surface of cured silicone gel. The handling difficulty related to sex is eliminated. When minute vibrations and shocks are transmitted to the cured body of silicone gel through the outer cover, the silicone gel disperses energy in all directions and also deforms to buffer the vibrations and shocks. . Also,
The operating temperature range is wider than when a thermoplastic elastomer or a thermosetting resin is used as the outer cover.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1 and FIG. 2, the buffer body 1 is a hollow casing body 2 made of silicone rubber having JIS A rubber hardness of 20 to 80 Hs.
A silicone gel hardened body 3 having a penetration of 50 to 150 according to a petroleum / asphalt penetration test JIS K2530 is filled and sealed in the inside of the container. The outer cover 2 includes a sheet 4 made of the silicone rubber having a bulged portion 4a formed on one side, and a layer 13a formed by curing a liquid silicone rubber 13 applied as an adhesive on the other side of the sheet 4. A thin plate 5 formed of a silicone rubber having the same rubber hardness as described above and adhered to the sheet 4 with the liquid silicone rubber 13, and one surface of the thin plate 5 has an adhesive 6 and a peeling sheet. 7
Are wearing. As is clear from FIGS. 1 and 2, the thin plate 5 is formed in a flat plate shape, and the flat portion 4b is provided on the surface of the bulging portion 4a of the sheet 4, and the flat portion 4b and the thin plate 5 are formed. They are almost parallel to each other. As an example of using this cushioning body, for example, considering the case where a precision instrument (or a part thereof) is placed on a flat support surface via this cushioning body, the peeling sheet 7 is peeled off and the adhesive 6 is used. It is only necessary to attach this shock absorber to the bottom surface of precision equipment. In this state, the flat surface portion 4b of the bulging portion 4a of the buffer body serves as a contact portion with the support surface, and the precision instrument is stably supported by the buffer body in a vibration-proof manner. Also, FIG. 3 (a) and FIG.
A plurality of buffer bodies 1 connected in the vertical and horizontal directions shown in FIG.
Are formed at the same time, and the notch 8 is provided so that each buffer body 1 can be cut and separated. In this way, since the outer cover 2 is a thin film, the buffer 1
A certain level of bending fatigue strength is required to function as, but silicone rubber normally has a rubber hardness of 10 to 90.
There is a range of Hs, and if less than 20Hs is used, the bending fatigue strength becomes small, so that it easily breaks and cannot be put to practical use. On the other hand, if it is greater than 80 Hs, the unvulcanized rubber does not easily flow in the mold when the outer casing 2 is molded, making it difficult to form a thin outer casing 2. Furthermore, in the buffer body 1 made with the jacket 2 larger than 80Hs,
When an impact is applied, the transmission from the outer cover 2 to the silicone gel cured body 3 is poor, and the function as the buffer body 1 cannot be sufficiently exhibited. Therefore, the rubber hardness of the jacket 2 is preferably 20 to 80 Hs. On the other hand, if the penetration of the cured silicone gel 3 is greater than 150, it is difficult to deform when a shock is applied, and a time delay (time lag) occurs even if the deformation occurs, so the effect of shock absorption becomes small. I will end up. Also,
When the penetration is less than 50, it is difficult to adjust the hardness and it is difficult to maintain the shape of the buffer 1. Therefore, the penetration of the cured silicone gel body 3 is preferably 50 to 150, and this range is easy to absorb impact.

The buffer body 1 having the above-described configuration is produced, for example, as follows.

First, as shown in FIG. 4, an uncrosslinked silicone rubber (Shin-Etsu Chemical Co., Ltd. rubber compound KE951U was added to accelerator C).
8A (0.5 parts mixed) 4b is set in a hot press mold 9. In this case, the male die 9a of the hot press die 9 is provided with a plurality of mountain ridges 9c arranged vertically and horizontally at appropriate intervals, and the female die 9b is formed with a recess 9d corresponding to the mountain die 9c. ing. Then, the hot press die 9 is heated to 170 ° C., the uncrosslinked silicone rubber 4b is placed between the male die 9a and the female die 9b, and the temperature is 180 k.
Pressing is performed at a pressure of g / cm ² for 10 minutes to perform press molding, and at the same time, a sheet 4 made of crosslinked silicone rubber is produced. By doing so, as shown in FIG.
A plurality of locations on one side (lower side in the figure) bulge to form a hollow portion 10, and an opening 12 is formed on the other side of the sheet 4 (upper side in the figure) to form a portion of the casing 2. A plurality of bulged portions 4a are integrally formed.

Next, as shown in FIG. 6, the bulging portion 4a is fitted into the female mold 11 for holding its outer shape, and the opening 12 is placed in the upward state. In this state, the hollow portion 10 is filled with the liquid silicone gel 3a (Shin-Etsu Chemical Co., Ltd. KE1052 A: B = 1: 1 weight ratio mixture) to the same height as the opening 12. Then, the liquid silicone gel 3a is heated at 200 ° C. for 5 minutes by a heating device (not shown) to be cured to have a penetration of 50 to 150.
Preferably, the cured silicone gel 3 has a penetration of 65.

On the other hand, as shown in FIG. 7, the silicone rubber is formed into a thin plate 5 having a thickness of 0.2 to 2.0 mm, preferably 0.5 mm in a separate step,
An acrylic resin adhesive 6a (Nitto Denko Corporation NO.5203) is applied to one surface (upper surface in FIG. 7) of the thin plate 5.
Next, as shown in FIG. 8, a room temperature-curable liquid silicone rubber 13 (KE441T, Shin-Etsu Chemical Co., Ltd.) having a viscosity of 50 to 1000 poise, preferably 100 poise is applied to the opening 12 side of the sheet 4. Then, the other surface of the thin plate 5 is polymerized on the upper side thereof and left at room temperature for 10 hours to bond and integrate them.

In this way, the silicone gel cured body 3 is placed in the hollow portion 10.
Since the envelope body 2 in which is encapsulated is used after being cut and separated for each single buffer body 1, as shown in FIG. 9, a half cut machine 14 is used to make a cut 8 in the bonded portion. To provide. At this time, if a peeling sheet 7 that further covers the acrylic resin-based adhesive material 6a adhered to one surface of the thin plate 5 is stuck, if the peeling sheet 7 is left without cutting, It is convenient because a plurality of buffer bodies 1 can be handled as one set until the time of use.

In addition, in the above-mentioned embodiment,
Not only the above-described press molding but also injection molding can be performed, and the shape of the molded outer casing 2 is not limited to this embodiment.

Next, for comparison, a test piece A (rubber material: silicone rubber 70Hs) having the same shape as that of the jacket 2 of the above-mentioned example was formed, and a comparative test of impact absorbing power was performed. The test method is as shown in FIG. 10, in which a weight 15 of 10 g is suspended and hung in an inclined state at an angle of 45 °, and then shaken off to collide with the test piece A or the buffer 1 of the above-mentioned embodiment. Then, the pickup sensor 16 (ENDEVCO 215E) senses the impact force, transmits the signal to the charge amplifier 17 (NEC Sanei 6D07), and further the analyzing recorder 18 (Yokogawa Kitatsu Electric Co., Ltd.). MODEL 3655) was used to display the converted acceleration. The results are shown in Fig. 11.

According to these results, the shock absorption a of the shock absorber 1 of the present invention (solid line in FIG. 11) is clear from the fact that there is no abrupt increase / decrease in acceleration in the graph of FIG. In addition, the absorption of impact force by the conventional rubber material b (11th
It was found to be better than the (chain line in the figure) and suitable as a shock absorber that absorbs vibrations and shocks even when attached to precision equipment.

〔The invention's effect〕

As is clear from the above description, according to the cushioning body and the manufacturing method thereof of the present invention, the silicone gel cured body is easily deformed in the state of being encapsulated in the silicone rubber to disperse the energy of vibration and impact. It is suitable as a cushioning member for various precision instruments, and has improved mechanical strength such as tensile strength and strength against compressive load compared to the case of silicone gel alone, and since the surface of the cushioning body does not stick, handling is easy. It is convenient and has a wider operating temperature range than the case where a thermoplastic elastomer or a thermoplastic resin is used as the jacket. Furthermore, the thin plate forming the outer cover is coated with the adhesive material to facilitate the attachment to various precision equipment, and the crosslinked silicone rubbers are firmly adhered to each other by the liquid silicone rubber to form the outer cover. Since the buffer body is formed and the manufacturing method of the buffer body is easy, it has a high industrial value suitable for mass production.

[Brief description of drawings]

1 to 9 show an embodiment of the present invention, FIG. 1 is a perspective view of a cushioning body, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. FIG. 3 (b) is the same plan view, FIG. 4 to FIG. 9 are vertical cross-sectional views for explaining the manufacturing process of the shock absorbers, FIG. 10 and FIG. FIG. 10 shows a comparative example of shock absorbing power between a shock absorbing body which is an embodiment of the invention and a conventional shock absorbing body, FIG. 10 is an explanatory diagram of a method of measuring the shock absorbing power, and FIG. 1 ... Buffer, 2 ... Envelope, 3 ... Silicone gel cured body, 3a ... Liquid silicone gel, 4 ... Sheet, 4a ... Swelling part, 5 ... Thin plate, 6 ... Adhesive material , 10 …… Hollow part, 13 …… Liquid silicone rubber.

Claims (2)

[Claims] 1. A sheet made of silicone rubber having a rubber hardness of 20 to 80 Hs and having a bulged portion on one side, a silicone gel cured body having a penetration of 50 to 150 filled in the bulged portion, and a rubber hardness. A flat thin plate that is bonded to the other side of the sheet via an adhesive layer made of silicone rubber of 20 to 80 Hs and encloses the cured silicone gel between the sheet, and the sheet in this thin sheet. And a pressure-sensitive adhesive material attached to the surface opposite to the surface to be joined to the thin plate, and a flat body substantially parallel to the thin plate is provided on the surface of the bulging portion of the sheet. 2. A sheet made of silicone rubber is formed with a plurality of hollow bulging portions on the other side of the sheet, and a plurality of hollow bulging portions are formed, and the hollow portion of the bulging portion is filled with liquid silicone gel. This liquid silicone gel is cured to give a penetration of 50.
~ 150 silicone gel hardened material, separately coated with adhesive material on one side of a thin plate made of silicone rubber, and the other side of this thin plate bonded to the other side of the sheet with liquid silicone rubber A method for manufacturing a buffer body, comprising forming a plurality of outer casings for sealing the cured silicone gel body, and then cutting and separating each outer casing body.