受験番号：14IPM008============================================================================[問１][0003]
When a metal product or the like is subjected to high-temperature treatment in a high-temperature
furnace, an endless chain-like conveyor belt is used to convey the metal product in the furnace. This
chain-like conveyor belt includes a number of chains or spirals, and heat-resistant steel wires are used
for the material of chain rods that connect the chains or spirals. However, the bending strength of thechain rod is as low as 3 kg/mm2 at a maximum in an atmosphere of 1000°C to 1200°C. Therefore, thefollowing problems may arise. That is, the rod is deformed in a short period of time. In addition, a
uniform shear force no longer acts on the connecting portions between the rods and the chains or spirals,
and thus a large shear force acts locally. As a result, the chains or spirals are broken, and the belt
makes an irregular meandering movement, thereby making the conveyor unusable.
[0004]A conveyor belt containing carbon fiber-reinforced carbon is known in the related art. The strengthof such a conveyor belt tends to increase in an atmosphere of up to 2500°C as compared to the atmosphereof room temperature. However, it is not desirable to use this type of conveyor belt in an oxidizing
atmosphere which may react with carbon.
[0005]
While the conveyor belt goes around in circles inside the furnace, an especially high tension actson the rods that are assembled in the lateral direction with respect to the moving direction of the belt.
In other words, a substantially perpendicular shear force acts on the rods. Therefore, it is necessary toreliably impart a tensile strength particularly to this portion of the rod that is subjected to the shear
force, that is, to impart a shear-resistant strength with respect to the direction substantiallyperpendicular to the longitudinal direction of the rod.
[問２][0039]
A rotary valve according to an embodiment of the present invention will be described below using anexample where the rotary valve is installed in a flow path of leading air in a stratified scavenging
two-cycle engine. However, the usage of the rotary valve is not limited to this example. The rotary valve
may be used as a fluid control valve to be installed between fluid flow paths. In addition, the rotary
valve can control, for example, the flow rate of fluid such as liquid and gas, as well as that of air.
Therefore, the present invention is not limited to the embodiment described below, but can be modified invarious ways.
[0040]In a stratified scavenging two-cycle engine 1, a piston 3 is slidably fitted into a cylinder 2. Thecylinder 2 is attached to an upper portion of a crankcase 6. A crankshaft 8 is rotatably attached to thecrankcase 6. One end of a crank 9, which is rotatably supported in a crank chamber 7, is coupled to thecrankshaft 8. The piston 3 is also coupled to the crankshaft 8 via a connecting rod 4. An ignition plug 5
is attached to the top of the cylinder 2. When an air-fuel mixture that has been compressed in a cylinderchamber C is ignited by the ignition plug 5 at the top dead center of the piston 3, the air-fuel mixture
explodes to push the piston 3 downward.
[問３]
1.
An even balance provided with a pan on which an object to be measured is placed and a pan on whicha counterweight is placed, the even balance comprising:a stand including front and rear support plates facing and separated from each other, V-shaped
fulcrum members at upper ends of the front and rear support plates, and reverse V-shaped fulcrum members at
intermediate positions in a height direction just below the V-shaped fulcrum members of the front and rear
support plates;
an upper swing arm including a pair of front and rear swing fulcrum protrusions supported on theV-shaped fulcrum members in the middle of the longitudinal direction thereof, and V-shaped grooved hooks atboth ends in the longitudinal direction thereof;a lower swing arm including another pair of front and rear swing fulcrum protrusions supported on
the reverse V-shaped fulcrum members in the middle of the longitudinal direction thereof, and reverse
V-shaped grooved hooks at both ends in the longitudinal direction thereof; anda pair of right and left vertical lift rods including, at each lower end thereof, a pair of windows
into which the hooks at both ends of the upper and lower swing arms are movably inserted, the V-shaped
grooves and the reverse V-shaped grooves being engaged with each other while the upper and lower swing arms
are in parallel to each other between an upper side portion of an upper window and a lower side portion ofa lower window.

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