JPH02253023A - Cold-resistant shock absorber - Google Patents

Abstract

PURPOSE:To enhance the shock relaxation and the flexibility at a low temperature by forming a plurality of holes in a synthetic planar molded body, and by integrally incorporating spring members each having quadratic surface and bulging into the holes, with the molded body. CONSTITUTION:A cold resistant shock absorber used for a safety cover for a lift support column in a skin area of used in a refrigerator is composed of a synthetic resin planar molded body 1 formed therein a plurality of holes 2 at suitable positions thereon, and convex leaf spring like resilient members 3 each having a quadratic surface bulging into each of the holes, and integrally incorporated with the molded body 1. Polynorbournane group resin which is obtained by block-ring-opening polymerization of norbournane group monomer having more than three rings, or the like is used as the synthetic resin which constitutes the planar molded body and which therefore excels in heat- deformation resistance and mechanical strength and has a low flexibility. Thus, it is possible to enhance the aesthetical view, the cold resistance and the durability.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cold-resistant impact cushioning material, and more specifically,
Made of synthetic resin such as polynorbornene resin,
The present invention relates to a cold-resistant shock-absorbing material in which a leaf spring-like spring member is integrally molded. The cold-resistant impact cushioning material of the present invention has excellent impact resistance and flexibility at low temperatures, and can be particularly suitably used as a safety cover for a lift support at a ski resort, a cushioning member in a freezer, etc. .

[Prior Art] There are many accidents in which skiers crash into lift supports at ski resorts, resulting in death or injury. To this end, each ski resort has implemented measures such as (1) piling up snow at the bottom of the lift support, (2) wrapping a foam mat, (3) wrapping an air mat, and (4) wrapping snow around the lift support. Various measures are taken to cushion the impact, such as creating a gap with a spacer and covering it with a net, or (5) stretching a cone-shaped net around the lift column.

However, method (1) of piling up snow is uneconomical because the snow at the bottom of the lift support is likely to be blown away by the wind, requiring frequent piling work.

Method (2) is currently widely used, but foam-containing mats absorb moisture and increase in weight, so the installation position must be adjusted up or down depending on changes in snowfall. It is difficult to If the installation position of the mat is not adjusted in response to the increase in snowfall, wind pressure will cause the area around the mat to become wedge-shaped, compromising safety. Moreover, the mats must be removed during the off-season due to aesthetic concerns.

(3) Air mats often have punctures due to the stock sticking out, or air leaks.

The netting methods (4) and (5) have problems such as skiers easily getting caught in the net, collisions with spacers, frequent maintenance, and difficulty in correcting the vertical position.

Incidentally, there are two main causes of skier casualties caused by lift props: collision with the prop, and getting caught in the prop, base magnetic parts (anchors, reinforcing ribs), ladders, shock-absorbing covers, etc. We can separate.

Therefore, it is desirable that the lift column safety cover (impact buffering cover) be made of a material and shape that effectively reduces the impact of a collision, prevents the tip of the ski or the skier's body from getting caught, and is easy to slip. It will be done. In addition, it is easy to adjust the vertical position according to the amount of snow,
It does not lose its beauty even if it is not removed during the off-season, it has excellent weather resistance and durability, it is easy to disassemble and is lightweight when it is removed, it is small when stored, and it is inexpensive. Many characteristics are desirable, such as: Furthermore, at ski resorts, there is more than just lift support (
A shock-absorbing material that can be applied to standing trees, building walls, etc. is desired.

However, the conventional glue 71 to pillar safety cover is insufficient in terms of safety, appearance, weather resistance, durability, and workability (attachment, removal, vertical movement, etc.).

For example, if a cold-resistant shock-absorbing material can be applied to the wall surface of a freezer compartment of a refrigerator car, damage caused by collisions with products can be prevented.

As described above, impact-resistant shock absorbing materials having cold resistance are desired for various uses such as safety covers for ski lift columns at ski resorts, but all conventional materials are insufficient.

[Problem to be Solved by the Invention 1] As a result of intensive research in order to solve the problems of the above-mentioned prior art, the present inventors found that injection molding and reaction injection molding (RIM)
) is possible, and has a plurality of holes (openings) in a plate-shaped molded body made of a synthetic resin that has excellent outdoor durability, and has a quadratic curved surface overhanging the hole, for example, It has been discovered that a cold-resistant impact cushioning material can be obtained by integrally molding a leaf spring-like spring member.

This shock absorbing material can be easily molded by injection molding or RIM using various synthetic resins, and when used by bringing the tip of the spring member (the convex tip portion of the quadratic curved surface) into contact with the mating material, The limit of deformation due to impact is large, and the impact of impact objects can be effectively reduced.

In addition, among synthetic resins, the present inventors have discovered that polynorbornene-based resins obtained by bulk ring-opening polymerization of tricyclic or higher norbornene-based monomers in the presence of a metathesis catalyst system in a mold can be used at room temperature. Not only does it have high impact resistance, but there is little change in impact resistance, elastic modulus, flexibility, etc. even at low temperatures, and large molded products can be easily molded by the RIM method, which achieves the objective of the present invention. We have found that this is particularly preferable.

The shock absorber made of polynorbornene resin has great flexibility and can be easily bent by applying an external force even at room or low temperatures, so it is formed into a cylindrical shape to wrap around cylinders such as lift columns. Suitable as a lift column safety cover. In addition, a lift column safety cover with this shape can reduce the impact speed in the event of a head-on collision with a skier, and
If it enters from any other angle, the tip of the ski and the skier's body will be caught, and the angle of incidence will shift to a safe direction during the impact stroke.

The present invention has been completed based on these findings.

[Means to solve the problem]

Thus, according to the present invention, there is provided a plate-shaped molded body made of synthetic resin, the plate-shaped molded body having a plurality of holes and a quadratic curved surface extending above the hole. A cold-resistant shock-absorbing material is provided in which a spring member is integrally molded.

The cold-resistant shock absorbing material of the present invention can be particularly suitably used as a lift column safety cover formed to surround a lift column so that the tip of the spring member comes into contact with the outer peripheral surface of the lift column.

In addition, the cold-resistant impact cushioning material of the present invention can not only be used as an impact cushioning member by itself (but also can be used as a sheet shock absorbing member by combining two sheets so that the tips of each spring member are in contact with the back surfaces of each other). The buffer member can cover protected members of various shapes.

Hereinafter, the constituent elements of the present invention will be explained in detail.

(Cold-resistant impact cushioning material) The cold-resistant impact cushioning material of the present invention is a plate-shaped molded body made of synthetic resin, the plate-shaped molded body having a plurality of holes,
In addition, the spring member has a shape in which a spring member having a quadratic curved surface extending above the hole is integrally molded.

The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram (partial diagram) showing one embodiment of the spring member in the cold-resistant impact cushioning material of the present invention, in which holes 2 and a core shape are formed on a plate-shaped body 1 made of synthetic resin. A spring member 3 having an overhanging quadratic curved surface is integrally molded. The spring member shown in FIG. 1 has a convex plate spring shape.

In addition to this, the shape of the spring member may be, for example, a convex plate spring with one end separated as shown in FIG. 2, or, for example, as shown in FIG. The plate springs may have a crossed shape. However, the spring member needs to have a quadratic curved surface. for example,
If the convex shape (cubic curved surface) is simply formed into a bowl shape, it is difficult to absorb impact and deform.

The cold-resistant impact cushioning material of the present invention has a structure in which a plurality of such holes and a spring member having a quadratic curved surface projecting above the holes are provided in a plate-shaped molded body made of synthetic resin. A specific example is shown in FIG. FIG. 4(B) shows an example of a shock absorbing material having a structure in which a plate-shaped molded body 1 has a plurality of vertically elongated holes 2 provided at regular intervals above and below. Figure 4 (A) shows the fourth
FIG. 2 is a cross-sectional view taken along the line XX' in FIG. Further, FIG. 4(C) is a sectional view taken along the line YY' in FIG. 4(B), and shows that the spring member 3 forms a convex mountain shape.

The location and number of holes and spring members can be determined as appropriate depending on the purpose of use. For example, in FIG. 4 fB), the holes and the spring members can be installed only in the upper part of the plate-shaped molded body. Further, the shape of the hole can be various shapes such as a horizontally long rectangle or a circle, in addition to the vertically long rectangle shown in FIG. 4(B).

(Lift Strut Safety Cover) FIGS. 5 to 8 are diagrams showing specific examples in which the cold-resistant shock absorbing material of the present invention is applied to a lift strut safety cover of a ski resort.

FIG. 5 is a sectional view showing an example of a cylindrical lift column safety cover in which three shock absorbing materials 1 are bent and the tips of the respective spring members 3 are brought into contact with the outer peripheral surface of the column 5. In order to fix this shock absorbing material to the lift column, for example, a belt may be passed through the internal space of each spring member 3 and tied to the column. In order to bend such a plate-shaped molded product, it is preferable to use a polynorbornene resin with excellent flexibility as the material. Further, FIG. 5 shows an example in which a protection member 4 is provided to cover a ladder 6 attached to a lift support column. This protective member is also made of synthetic resin, and the spacing between the protective members 4.4 is narrow enough to prevent a person's head from getting caught, but wide enough to allow a ladder to be used.

FIG. 6 is a schematic external view of a lift column safety cover using the cold-resistant shock absorbing material of the present invention.

Figure 7 shows cylindrical shock absorbers 1.11 and 11.
1 is a front view showing an example of a lift column safety cover having a stacked shape. The cylindrical shock absorbing material located above is locked by the spring member and will not slide downward. By stacking shock absorbing materials in this way,
It is possible to cope with an increase in snowfall. Of course, each cylindrical shock absorbing material is lightweight and does not contain moisture, so it can be moved up and down according to changes in snowfall.

Reference numeral 9 in FIG. 7 indicates an example of a planar impact buffering member that covers the base portion (anchor, reinforcing rib, etc.) of the lift column. Specifically, as shown in Fig. 8, two pieces of cold-resistant impact cushioning material (1, 11) are placed around the reinforcing rib 7 at the bottom of the lift column 1 so that the tips of each spring member are in contact with the back surfaces of each other. It is surrounded by four sets of planar shock absorbing members having a combination of shapes. Here, the two pairs of impact cushioning materials used are such that one of the holes and the spring member is placed in the upper part of the plate-shaped molded body.
The other is provided in the lower part, and each spring member is arranged to abut against the back surface of the respective plate-like body. The two pairs of shock absorbing materials can be connected, for example, by rivets, screws, or the like at the abutting portions of the respective spring members. Further, 8 in FIG. 8 is a cover for connecting the planar shock absorbing members, which can also be fastened with rivets, screws, or the like.

(Synthetic resin) The synthetic resin used in the present invention may be either a thermoplastic resin or a thermosetting resin as long as it can be injection molded or reaction injection molded and has excellent outdoor durability. often,
For example, polyethylene, polypropylene, ABS resin,
Examples include polycarbonate, polyester, polyamide, epoxy resin, and polynorbornene resin.

Among these synthetic resins, polynorbornene resins, which are obtained by bulk ring-opening polymerization of tricyclic or larger norbornene monomers such as dicyclopencdiene in the presence of a metathesis catalyst system in a mold, are heat-resistant. It not only has excellent deformability and mechanical strength, but also has high impact resistance at room temperature.
It is particularly preferred as a book that achieves the purpose of the present invention because it has little change in impact resistance, elastic modulus, flexibility, etc. even at low temperatures, can be easily molded into large molded products by the RIM method, and is inexpensive. .

Hironori Norbornene, ′ When the norbornene monomer is tricyclic or more, a polymer having a high heat distortion temperature can be obtained. Bulk ring-opening polymerization of tricyclic or higher norbornene monomers produces solvent-insoluble crosslinked polymers, but in order to increase the degree of crosslinking of the polymer, at least 10% by weight of the total monomers,
It is preferable to use 30% by weight or more of a crosslinking compound.

Examples of norbornene monomers having tricyclic or higher structures include tricyclics such as dicyclopentadiene and dihydrodicyclopencdiene, tetracyclics such as tetracyclododecene, and pentacyclics such as tricyclopentadiene. , heptacyclics such as tetracyclopentadiene, alkyl substituted products thereof (e.g., methyl, ethyl, propyl, butyl substituted products, etc.), alkylidene substituted products (e.g., ethylidene substituted products, etc.), aryl substituted products (e.g., phenyl, tolyl substituted products, etc.).

On the other hand, the crosslinking monomer is a polycyclic norbornene monomer having two or more reactive double bonds, and specific examples thereof include dicyclopentadiene, tricyclopentadiene, and tetracyclopencdiene. Therefore, when the norbornene monomer and the crosslinking monomer are the same, there is no need to use any other crosslinking monomer.

These norbornene monomers may be used alone or in combination of two or more.

In addition, monomers such as 2-norbornene, 5-methyl-2-norbornene, 5-ethylidene-2-norbornene, and 5-phenyl-2-norbornene, which can undergo ring-opening polymerization with one or more of the tricyclic or more norbornene monomers mentioned above, Cyclic norbornene monomers or monocyclic cycloolefins such as cyclobutene, cyclopentene, cyclopentadiene, cyclooctene, and cyclododecene can be used in combination without impairing the purpose of the present invention.

The metathesis catalyst system may be any metathesis catalyst system that is known as a catalyst for bulk polymerization of norbornene monomers (for example, JP-A-581-27728; JP-A-581-27728;
No. 8-129013, No. 59-51911, No. 60-
No. 79035, No. 60-186511, No. 61-12
No. 6115, etc.), there are no particular restrictions. Examples of the metathesis catalyst include halides, oxyhalides, oxides, and organic ammonium salts of tungsten, molybdenum, tantalum, and the like.

Examples of the activator (cocatalyst) include alkyl aluminum halides, alkoxyalkylaluminum halides, aryloxyalkylaluminum halides, and organic tin compounds.

The amount of the metathesis catalyst is usually about 0.01 to 50 mmol, preferably 0.01 mmol to 1 mol of norbornene monomer.
It is used in a range of 1 to 10 mmol. The activator (cocatalyst) is generally used in an amount of 0.1 to 200 (mole ratio), preferably 2 to 10 (mole ratio), based on the catalyst component.

Both the metathesis catalyst and the activator are preferably used after being dissolved in a monomer, but they may also be used after being suspended or dissolved in a small amount of a solvent as long as the properties of the product are not essentially impaired.

The polynorbornene resin used in the present invention can be obtained by bulk ring-opening polymerization of a norbornene monomer in a mold (form) in the presence of a metathesis catalyst system and an elastomer. Substantially bulk polymerization may be used, but from the viewpoint of the physical properties of the molded product, it is desirable not to use an inert solvent in the preparation of the catalyst.

In a preferred method for producing a molded article, the norbornene monomer is divided into two liquids and placed in separate containers, and a metathesis catalyst is added to one and an activator to the other to prepare one stable reaction solution. These two types of reaction solutions are mixed and then poured into a mold, where ring-opening polymerization takes place in bulk.

The injection pressure is not particularly limited, but usually 10 kg/crrr or less is sufficient, and the injection is preferably carried out under normal pressure. Mold temperature is usually 30°C or higher, preferably 40 to 200°C
, particularly preferably from 50 to 130°C. The mold pressure is
Usually, it is in the range of 0.1 to 100 kg/cnf. In addition, the polymerization time may be selected appropriately, but it is usually 2 minutes to 1 minute.
It takes about an hour.

The components used in the polymerization reaction are preferably stored and operated under an inert gas atmosphere such as nitrogen gas. The mold may be sealed with an inert gas, but it is not necessary.

As for the mold, a combination of a convex mold and a concave mold is usually used to form the hole and the spring member.

By blending various additives such as elastomers, antioxidants, fillers, colorants, polymer modifiers, flame retardants, and sliding agents, the properties of the molded article can be modified.

(Applications) The cold-resistant shock-absorbing material of the present invention can be used in various fields, such as safety covers for ski-shaped lift columns and shock-absorbing members in freezers.

(The following is a blank space) [Example] The present invention will be described in more detail with reference to Examples below, but the present invention is not limited only to these Examples. Note that parts, percentages, etc. are based on weight unless otherwise specified.

[Example 1] Phenolic antioxidant (trade name Irganox 101
0, manufactured by Ciba Geigy) [i.e., 85% dicyclopentadiene (DCP)].
and a 15% mixture of cyclopentadiene trimer] were placed in two containers, and one contained 0.4 parts of diethylaluminum chloride (DEAC) per 100 parts of the monomer mixture.
part, n-propertool 0.15 part, silicon tetrachloride 0
．． 36 parts, and 6 parts of a styrene-isoprene-styrene block copolymer (Krayton 1170, manufactured by Shell) were added (liquid A). On the other hand, 0.3 parts of tri(tridecyl)ammonium molybdate was added to 100 parts of the monomer mixture (liquid B).

Liquid A and liquid B are each sent to a power mixer using a gear pump at a volume ratio of 1:1, and then the mold temperature is increased within the mold space formed by the convex mold and the concave mold. Injections were made at 70°C.

The reaction was carried out in the mold for 3 minutes. These series of operations were performed under a nitrogen atmosphere.

Then, as shown in Figure 4, the length is 800mm x width 880mm
A plate-shaped molded body with a thickness of 2.5 mm, which has five holes each on the top and bottom with a width of 50 mm and a length of 150 mm, and a plate-shaped spring (spring member) with a width of 45 mm and a height of 100 mm is integrally molded. I got the cushioning material.

The heat distortion temperature of the obtained molded body was 140°C (JIS K
-6911, load 8.5 kg), specific gravity is 1.04 g/
crd, and the bending elastic modulus of the plate-shaped molded body is 190k.
g/mrrf' (JIS K-7203), Izod impact strength is 30kg-cm/cm [JIS
K7110 6.5 (with notch)], it has rigidity and flexibility, is lightweight, and has excellent heat resistance and impact resistance.

As shown in Fig. 5, three pieces of this shock absorbing material are combined and bent so that the spring member comes into contact with the outer peripheral surface of the cylindrical support.
A belt was passed through the internal space of each spring member and fixed to the support. This impact cushioning material can be easily bent,
No cracking occurred.

Also, when I applied a load and pushed it, the spring member deformed.
It functioned as a leaf spring.

〔Effect of the invention〕

The cold-resistant impact cushioning material of the present invention has excellent impact resistance and flexibility at low temperatures, and can effectively alleviate the impact of a collision. The skier's body is less likely to get caught, and the angle of incidence moves in a safe direction during the collision stroke. In addition, it is easy to adjust the vertical position according to the amount of snowfall, has excellent appearance, weather resistance, and durability, and is easy to disassemble when removed, is lightweight, and does not take up much bulk when stored. It is small (and inexpensive) and can be suitably used as a safety cover for a ski lift column or a buffer member in a freezer.

[Brief explanation of drawings]

1 to 3 are examples showing the structure of holes and spring members of the cold-resistant shock absorbing material of the present invention. FIGS. 4 to 8 are views showing examples in which the cold-resistant shock absorbing material of the present invention is used in a lift column safety cover. 1. Plate-shaped molded body, 2.. Hole, 3. Spring member 5
・Lift pillar

Claims (5)

[Claims] (1) A plate-shaped molded body made of synthetic resin, the plate-shaped molded body having a plurality of holes, and a spring member having a quadratic curved surface extending above each hole is integrally formed. A cold-resistant impact cushioning material characterized by being molded into. (2) The cold-resistant impact cushioning material according to claim 1, wherein the synthetic resin is a polynorbornene resin obtained by bulk ring-opening polymerization of tricyclic or larger norbornene monomers. (3) A lift column safety cover formed of the cold-resistant impact cushioning material according to claim 1 or 2. (4) The lift column safety cover is formed so as to surround the lift column using one or more of the shock absorbing materials so that the tips of the spring members are in contact with the outer peripheral surface of the lift column. Lift post safety cover described in 3. (5) A planar impact-absorbing member formed by combining two sheets of the cold-resistant impact-absorbing material according to claim 1 or 2 so that the tips of each spring member are in contact with the back surfaces of each other.