JP6401202B2 - Asphalt finisher - Google Patents

Description

  The present invention relates to an asphalt finisher, and more particularly, to an asphalt finisher that spreads a heated asphalt mixture stored in a hopper portion on a pavement surface with a predetermined thickness.

  Asphalt finisher, for example, when road asphalt paving, prior to rolling the heated asphalt mixture with a road roller, etc., the heated asphalt mixture is spread and leveled to a flat surface with a predetermined thickness. Therefore, it is a known construction vehicle that is generally used.

  The asphalt finisher has, for example, a hopper portion that stores a heated asphalt mixture charged from a dump truck, and the hopper portion usually has an asphalt mixture (heated asphalt mixture) heated to around 110 to 185 ° C. Is inserted. If the asphalt mixture is laid on the pavement surface in a state where the temperature is significantly lowered, it cannot be sufficiently compacted, and it becomes difficult to obtain a high-quality asphalt pavement. In addition, the heat of the heated asphalt mixture stored in the hopper part is likely to be released through the outer plate of the metal hopper other than coming into contact with the outside air. The decrease in temperature becomes significant.

  For this reason, various asphalt finishers have been developed that improve the hopper part so that the temperature of the heated asphalt mixture stored in the hopper part can be prevented from decreasing (for example, see Patent Document 1). . In the asphalt finisher of Patent Document 1, the outer plate of the hopper part is formed in a double structure holding a gap, and a heat insulating material is interposed in the gap part, or an exhaust passage is provided to vent the exhaust gas. Or by laying an electric heating body on the inner surface or the outer surface of the outer plate of the hopper or by attaching a heat insulating material, the temperature of the heated asphalt mixture is prevented from decreasing.

JP-A-11-209918

  However, in the asphalt finisher that can suppress the temperature of the heated asphalt mixture stored in the conventional hopper part from being lowered, it is widely used when the outer plate of the hopper part is formed in a double structure. The existing asphalt finisher will be forced to undergo major modifications, which will increase costs. Also, when attaching an electric heating element or heat insulating material to the inner surface of the outer plate of the hopper, it is necessary to prevent them from being damaged by the charged heated asphalt mixture. Become.

  The present invention makes it possible to impart a heat insulating function to the hopper part by a simple operation without requiring much labor, and effectively suppresses the temperature of the heated asphalt mixture stored in the hopper part from decreasing. An object of the present invention is to provide an asphalt finisher that can be used.

  The present invention has a hopper that stores the charged heated asphalt mixture, and in the asphalt finisher that spreads the heated asphalt mixture stored in the hopper portion with a predetermined thickness on the paved surface, the hopper portion is Covering at least the inner side surfaces of the movable hopper portions on both sides, a heat retaining plate is attached, and the heat retaining plate is a surface stainless steel plate disposed on the surface side in a state of being affixed to the inner surface of the hopper portion And the said objective is achieved by providing the asphalt finisher formed including the heat resistant heat insulating material arrange | positioned at the back surface side of this surface stainless steel plate.

  And as for the asphalt finisher of this invention, it is preferable that the said heat retention plate is formed including the back surface stainless steel plate arrange | positioned at the back surface side of the said heat resistant heat insulating material.

  In the asphalt finisher of the present invention, the heat resistant heat insulating material is preferably a silica heat insulating material.

  Furthermore, in the asphalt finisher of the present invention, it is preferable that the silica-based heat insulating material is made of a nonwoven fabric sheet impregnated with airgel.

  Furthermore, it is preferable that the asphalt finisher of the present invention has a heat conductivity of 0.02 to 0.09 W / mk and a heat resistant temperature of 0 to 600 ° C.

  According to the asphalt finisher of the present invention, it is possible to impart a heat insulating function to the hopper part by a simple operation without much labor, and the temperature of the heated asphalt mixture stored in the hopper part is reduced. Can be effectively suppressed.

1 is a schematic side view illustrating an overall configuration of an asphalt finisher according to a preferred embodiment of the present invention. 1 is a schematic plan view illustrating an overall configuration of an asphalt finisher according to a preferred embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS (a) of the hopper which comprises the asphalt finisher which concerns on preferable one Embodiment of this invention is a perspective view of the state before a heat retention plate is attached, (b) is a perspective view of the state to which the heat retention plate was attached. FIG. 3A is a plan view and FIG. 3B is a front view of a hopper portion to which a heat retaining plate shown in FIG. In an Example, it is a figure which shows the state which affixed the heat retention plate on the inner surface of the movable hopper part. It is a figure which shows the measurement result of the surface temperature of a movable hopper part. It is a figure which shows the measurement result of the temperature of the asphalt compound material stored by the hopper. It is a figure which shows the measurement result of the temperature of the asphalt compound material at the time of leveling.

  The asphalt finisher 1 according to a preferred embodiment of the present invention shown in FIGS. 1 and 2 is manufactured at an asphalt plant and transported by a dump truck having a size of about 11 t, for example, at a high temperature of about 110 to 185 ° C. When the asphalt mixture 10 (heated asphalt mixture) 10 heated to is put into the hopper 3 and laid on the paved surface 11, the temperature of the asphalt mixture 10 stored in the hopper 3 during laying decreases. It has a function that can be effectively suppressed with a simple configuration. That is, the quality of the asphalt pavement is closely related to the temperature when the asphalt mixture 10 is laid on the pavement surface 11, and in order to form a high quality asphalt pavement, the asphalt mixture 10 at the time of laying is used. It is important to suppress the temperature drop as much as possible. The asphalt finisher 1 of the present embodiment effectively suppresses the temperature of the asphalt mixture 10 stored in the hopper 3 from being lowered during laying by adding a simple improvement to a generally used asphalt finisher. Therefore, it is possible to form a high quality asphalt pavement.

  The asphalt finisher 1 of the present embodiment has a hopper portion 3 for storing an asphalt mixture (heated asphalt mixture) 10 charged from a dump truck (not shown), and the asphalt finish stored in the hopper 3. In the asphalt finisher 1 that spreads the material 10 on the pavement surface 11 of a base layer with a predetermined thickness, for example, covers the inner side surfaces of at least the movable hopper portions 30 on both sides constituting the hopper portion 3, and FIG. As shown also in (b), the heat retaining plate 31 is attached, and the heat retaining plate 31 is a surface disposed on the front surface side in a state of being attached to the inner surface of the movable hopper portion 30 of the hopper portion 3. Stainless steel plate 34 (see FIG. 3B, FIG. 4A, FIG. 4B) and the heat resistance of the surface stainless steel 34 disposed on the back side. It is formed and a timber 35.

  Moreover, in this embodiment, the heat retaining plate 31 is formed including the back surface stainless steel plate 36 disposed on the back surface side of the heat resistant heat retaining material 35 ((FIG. 3B, FIG. 4A, ( b))).

  In the present embodiment, the asphalt finisher 1 is provided with a vehicle main body 2 having an operator's driver's seat 20 and a front side in the traveling direction of the vehicle main body 2, as shown in FIGS. Is provided on the rear side in the traveling direction of the vehicle main body 2 and supplied to the pavement surface 11 from the rear opening 21 of the vehicle main body 2. The asphalt mixture 10 distributed in the width direction of the vehicle main body 2 and the surface of the asphalt mixture 10 distributed in the width direction by the screw spreader 4 are laid flat so as to have a predetermined thickness. A screed 5 and a road surface heating device 6 used for heating and softening an existing pavement adjacent to the pavement surface 11, a road pavement construction vehicle, Te has the same configuration and asphalt finisher device which is generally used.

  As shown in FIGS. 3 (a) and 3 (b), the hopper 3 is a pair of movable hoppers provided on both sides of a rectangular opening 32a in the center where the asphalt feeder 32 is disposed. 30, an asphalt feeder 32 that sequentially transfers the asphalt mixture 10 stored in the movable hopper 30 and fed downward from the rectangular opening 32 a toward the rear opening 21, a pair of the movable hopper 30 and the rectangular opening It is configured to include a pair of push rollers 33 and 33 that are disposed close to the front of the portion 32a.

  In the present embodiment, a pair of push rollers 33 and 33 provided in front of the pair of movable hopper portions 30 and the rectangular opening portion 32a are used as a pair of rear wheels of a dump truck (not shown) on which the asphalt mixture 10 is loaded. The asphalt finisher 1 is moved forward through the push rollers 33, 33 as the asphalt finisher 1 advances, and the asphalt composite 10 loaded on the dump truck bed is moved on both sides of the hopper 3. It is put into the area between the hopper parts 30. The asphalt mixture 10 that has been charged and stored in the region between the movable hoppers 30 is moved downward by its own weight as described above from the rectangular openings 32a sandwiched between the movable hoppers 30 on both sides. After being sent to the lower asphalt feeder 32, the asphalt feeder 32 passes through a conveyance path provided at the lower part of the vehicle main body 2 to the rear opening 21 provided at the rear end of the vehicle main body 2. It is sequentially transported towards. The transported asphalt mixture 10 is supplied to the pavement surface 11 as described above, then distributed in the width direction by the screw spreader 4, and further spread by the screed 5, and then by the subsequent load roller or the like. Compressed.

  In the present embodiment, the pair of movable hoppers 30 on both sides each include a bottom plate 30a, a side plate 30b, and a back plate 30c, and a rotation that is substantially parallel to the feeding direction by the asphalt feeder 32. It is provided in a state in which it is supported so as to be rotatable about a moving shaft 30d. That is, the movable hopper portion 30 has, for example, a bottom plate portion 30a connected to a hydraulic cylinder (not shown), and the bottom plate portion 30a is in a substantially horizontal state (usually in this state, asphalt composite material) 10 is loaded and stored in the hopper portion 3), and the outer portion of the bottom plate portion 30a is lifted so that the side plate portion 30b is tilted inwardly. It can be made to. As a result, the asphalt mixture 10 stored in the hopper 3 remains in the movable hopper 30 as it is sequentially transferred toward the rear opening 21 via the rectangular opening 32a and the asphalt feeder 32. The asphalt mixture 10 can be efficiently transported by sliding down toward the rectangular opening 32a and the asphalt feeder 32.

  In this embodiment, the heat retaining plate 31 is attached so as to cover the inner side surfaces of the bottom plate portion 30a, the side plate portion 30b, and the back plate portion 30c of each of the pair of movable hopper portions 30 constituting the hopper portion 3. . That is, as shown in FIG. 3B, the heat retaining plate 31 is formed into a plurality of sheets so as to have a shape corresponding to the shape of the inner surface side of the bottom plate portion 30a, the side plate portion 30b, and the back plate 30c of the movable hopper. In addition to being formed in a divided state, it is attached in a state where it is pasted using a known joining means such as an adhesive, bolt joining, welding joining or the like. The heat retaining plate 31 is preferably attached so as to cover the entire inner surface of the portion of the hopper portion 3 where the asphalt composite material 10 is stored. For this reason, the heat retaining plate 31 is attached so as to cover only the inner surface of the movable hopper 30 that constitutes the main part of the hopper 3 that stores the asphalt mixture 10.

  In the present embodiment, the heat retaining plate 31 is disposed on the surface stainless steel plate 34 disposed on the front surface side and attached to the back surface side of the surface stainless steel 34 in a state of being adhered to the inner surface of the movable hopper 30 as described above. And the back surface stainless steel plate 36 disposed on the back side of the heat resistant heat insulating material 35 (FIG. 3B, FIG. 4). a) and (b)).

  The surface stainless steel plate 34 is formed to be thinner than the thickness of the movable hopper 30 made of iron, and preferably has a thickness of 55% or more of the thickness of the movable hopper 30. In this embodiment, since the thickness of the outer plate of the hopper 30 is 9 mm, the thickness of the surface stainless steel plate 34 is preferably 5 mm or more. If the thickness of the surface stainless steel plate 34 is too large, the amount of heat of the asphalt mixture 10 may be taken more. On the other hand, when the thickness of the surface stainless steel plate 34 is too small, the asphalt mixture 10 may not be able to withstand the impact when dropped from the loading platform of the dump truck.

  By making the thickness of the surface stainless steel plate 34 thinner than the thickness of the movable hopper portion 30, the surface stainless steel plate 34 is asphalt as compared with the case where the inner surface of the movable hopper portion 30 is in direct contact with the asphalt mixture 10. It is possible to reduce the amount of heat to be taken away from the composite material 10. In particular, since stainless steel has a lower thermal conductivity than iron (stainless steel (SUS304): 16 W / mK, iron: 79 W / mK), the asphalt mixture 10 is less likely to lose heat. Moreover, since the surface stainless steel plate 34 does not easily release the heat taken from the asphalt mixture 10, the heat retention effect can be further enhanced.

  The heat-resistant heat insulating material 35 is preferably formed of a material having as low a heat transfer rate as possible, and the heat transfer rate is preferably 0.02 to 0.09 W / mk, more preferably 0.02 W / mk or less. is there. Moreover, it is preferable that the heat resistant heat insulating material 35 is formed of a material having a heat resistant temperature as high as possible, and the heat resistant temperature is preferably 0 to 600 ° C.

  As such a heat-resistant heat insulating material 35, a sheet made of silica-based heat insulating material can be used. The sheet | seat by a silica type heat insulating material is equipped with the above low heat transfer rates and high heat-resistant temperature. It is preferable to use a material as thin as possible for the sheet made of the silica-based heat insulating material, and the thickness of the sheet 35 made of the silica-based heat insulating material is preferably 3 mm or more and 10 mm or less, and more preferably 4 mm or more and 7 mm or less. In the present embodiment, a sheet 35 made of a silica heat insulating material having a thickness of 5 mm is used. If the thickness of the sheet 35 made of silica heat insulating material is larger than 10 mm, the heat insulating plate 31 becomes too thick, and is accommodated in the movable hopper 30 when it is attached to the inner surface of the movable hopper 30. There is a possibility that the storage amount of the possible asphalt mixture 10 may be reduced. On the other hand, if the thickness of the sheet 35 made of silica-based heat insulating material is smaller than 3 mm, the heat insulating effect by the heat insulating plate 31 may be reduced.

  Moreover, as the sheet | seat 35 by a silica type heat insulating material, it is preferable to use what consists of a nonwoven fabric sheet which impregnated the airgel. More specifically, a trade name “Pyrogel (registered trademark) XT” (manufactured by NICHIAS) known as a low heat conductivity flexible heat insulating material can be used.

  The back stainless steel 36 is attached in a state of being interposed between the movable hopper 30 and the heat-resistant heat insulating material 35. The back stainless steel plate 36 plays a role of blocking outside air from the outer surface of the movable hopper 30 toward the front stainless steel plate 34 (inner surface of the movable hopper 30).

  The back stainless steel plate 36 is formed to be thinner than the surface stainless steel plate 34, and preferably has a thickness of 60% or more of the thickness of the front stainless steel plate 34. In this embodiment, since the thickness of the front surface stainless steel 34 is 5 mm, the thickness of the back surface stainless steel 36 is preferably 3 mm or more.

  And, according to the asphalt finisher 1 of the present embodiment having the above-described configuration, it is possible to give a heat insulating function to the movable hopper portion 30 of the hopper portion 3 by a simple operation without requiring much labor. It becomes possible to suppress effectively that the temperature of the heating asphalt mixture (asphalt compound material) 10 stored by the hopper part 3 falls.

  That is, according to the asphalt finisher 1 of the present embodiment, since the heat retaining plate 31 is attached to the inner surface of the movable hopper 30 of the hopper 3, the asphalt mixture 10 is directly applied to the movable hopper 30 of the hopper 3. Since it does not contact, the heat loss of the asphalt mixture 10 by contacting the movable hopper part 30 of the hopper part 3 directly can be suppressed. In particular, the movable hopper 30 constituting the hopper 3 is generally made of iron, and the heat retaining plate 31 has a surface stainless steel plate 34, a heat resistant heat retaining material 35, and a back stainless steel plate having a lower thermal conductivity than iron. Since it has a three-layer structure having 36, it is possible to effectively suppress the heat loss of the asphalt composite material 10 that has been charged.

  In addition, according to the present embodiment, the hopper portion 3 is not required by a simple operation of simply attaching the heat retaining plate 31 to the inner surface of the movable hopper portion 30 of the hopper portion 3 of the general-purpose asphalt finisher. It is possible to easily obtain a heat insulating function that effectively suppresses a decrease in the temperature of the heated asphalt mixture (asphalt mixture) 10 stored in the container.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the heat insulating plate does not necessarily have a three-layer structure including a front surface stainless steel plate, a heat resistant heat insulating material, and a back surface stainless steel plate, and is a two-layer structure including a surface stainless steel plate and a heat resistant heat insulating material. It may be of a structure. Even in the case of using a heat insulation plate having a two-layer structure, the same effect as described above can be obtained. In addition to the silica-based heat insulating material, various other heat-resistant heat insulating materials having desired heat resistance and heat insulating properties can be used as the heat-resistant heat insulating material.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Example 1]
An asphalt finisher 1 having a hopper portion 3 shown in FIG. 3B was prepared. The thickness of the movable hopper 30 of the hopper 3 was 9 mm. The special plate (heat-retaining plate) 31 attached to the inner surface of the movable hopper 30 uses SUS304 having a thickness of 5 mm as the front surface stainless steel plate 34 and SUS304 having a thickness of 3 mm as the back surface stainless steel plate 36. . As the heat-resistant heat insulating material 35, a glass fiber nonwoven fabric sheet (trade name: Pyrogel (registered trademark) XT, manufactured by NICHIAS Corporation) containing airgel was used. The sheet made of this silica heat insulating material had a thermal conductivity of 0.02 mk, a heat resistance temperature of 650 ° C., and a thickness of 5 mm.

  These were laminated in the order of a front surface stainless steel plate 34, a heat resistant heat insulating material 35, and a back surface stainless steel plate 36, and a three-layer special plate (heat insulating plate) 31 was produced. The prepared special plate (heat insulation plate) 31 is cut in accordance with the uneven shape of the inner side surfaces of the bottom plate portion 30a, the side plate portion 30b, and the back plate portion 30c of the movable hopper portion 30, and the cut special plate (heat insulation plate) ) 31 was attached to the inner surface of each of the bottom plate portion 30a, the side plate portion 30b, and the back plate portion 30c of the movable hopper portion 30 (see FIG. 5).

(Measurement of surface temperature of movable hopper)
Three locations on each of the inner side surface of the bottom plate portion 30a and the inner side surface of the side plate portion 30b of the movable hopper portion 30, and three locations on each of the outer side surface of the bottom plate portion 30a and the outer side surface of the side plate portion 30b of the movable hopper portion 30 And the surface temperature of the movable hopper 30 was measured. The surface temperature was measured 30 minutes after the asphalt mixture 10 was added. The measurement results are shown in FIG.

(Measurement of the temperature of asphalt composite material put into the hopper)
The surface temperature and internal temperature of the asphalt plywood 10 stored in the hopper 3 were measured. The measurement was performed immediately after the asphalt mixture 10 was charged and after 30 minutes. The measurement results are shown in FIG.

(Measurement of the temperature of asphalt mixture during leveling)
The surface temperature and the internal temperature at the time of leveling the asphalt mixture 10 put into the hopper 3 were measured. The measurement results are shown in FIG.

[Comparative Example 1]
An asphalt finisher 1 having a hopper portion 3 in which the heat retaining plate 31 is not attached to the movable hopper portion 30 shown in FIG. The thickness of the movable hopper 30 of the hopper 3 was 9 mm. Using this, the same test as in Example 1 was performed. The measurement results are shown in FIGS.

[Evaluation]
As shown in FIG. 6, the movable hopper portion 30 with the special plate (heat retaining plate) 31 is attached to the inside of the bottom plate portion 30 a than the movable hopper portion 30 without the special plate (heat insulating plate) 31 attached. It turns out that temperature is 43 degreeC high and the internal temperature of the side-plate part 30b is also 12.2 degreeC high. In addition, the movable hopper portion 30 with the special plate (heat retention plate) 31 attached is more than the movable hopper portion 30 with no special plate (heat insulation plate) 31 attached, each of the bottom plate supply 30b and the side plate portion 30b. It turns out that the external temperature remains low and no heat is transferred to the movable hopper 30.

  In addition, as shown in FIG. 7, the asphalt composite material of the movable hopper portion 30 to which the special plate (thermal insulation plate) 31 is attached is more than the movable hopper portion 30 to which the special plate (thermal insulation plate) 31 is not attached. It can be seen that the rate of change in temperature (%) is low at any of the 10 surface temperatures and the internal temperature. That is, the surface temperature and internal temperature of the asphalt composite material 11 are higher in the movable hopper 30 to which the special plate (heat insulating plate) 31 is attached than in the movable hopper portion 30 to which the special plate (heat insulating plate) 31 is not attached. In any case, it becomes clear that the temperature is hardly lowered.

  As shown in FIG. 8, the movable hopper portion 30 with the special plate (heat retention plate) 31 attached is better than the movable hopper portion 30 with no special plate (heat insulation plate) 31 attached. It turns out that the internal temperature of the asphalt mixture 10 is higher by 11.6 ° C., and the surface temperature of the asphalt mixture during spreading is 28.7 ° C. higher. That is, the surface temperature and the internal temperature of the asphalt mixture 11 are greater in the movable hopper portion 30 to which the special plate (thermal insulation plate) 31 is attached than in the movable hopper portion 30 to which the special plate (thermal insulation plate) 31 is not attached. In any of the cases, it is found that the temperature is hardly lowered.

DESCRIPTION OF SYMBOLS 1 Asphalt finisher 2 Vehicle main body 3 Hopper part 4 Screw spreader 5 Screed 6 Road surface heating device 10 Heated asphalt mixture (asphalt mixture)
11 Pavement surface 21 Rear opening 30 Movable hopper 30a Bottom plate 30b Side plate 30c Back plate 30d Rotating shaft 31 Heat retaining plate 32 Asphalt feeder 32a Rectangular opening 33 Push roller 34 Surface stainless steel plate 35 Heat resistant heat insulating material (silica type) Thermal insulation)
36 Back stainless steel sheet

Claims (5)

In an asphalt finisher that has a hopper part that stores the charged heated asphalt mixture, and lays the heated asphalt mixture stored in the hopper part at a predetermined thickness on the paved surface,
Covering at least the inner surface of the movable hopper on both sides constituting the hopper, a heat retaining plate is attached,
The heat retaining plate is formed including a surface stainless steel plate disposed on the front surface side in a state of being attached to the inner side surface of the hopper portion, and a heat resistant heat retaining material disposed on the back surface side of the surface stainless steel plate. Asphalt finisher.   2. The asphalt finisher according to claim 1, wherein the heat retaining plate is formed to include a back surface stainless steel plate disposed on a back surface side of the heat resistant heat insulating material.   The asphalt finisher according to claim 1 or 2, wherein the heat-resistant heat insulating material is a silica-based heat insulating material.   The asphalt finisher according to claim 3, wherein the silica-based heat insulating material is a nonwoven fabric sheet impregnated with airgel.   The asphalt finisher according to any one of claims 1 to 4, wherein the heat-resistant heat insulating material has a thermal conductivity of 0.02 to 0.09 W / mk and a heat-resistant temperature of 0 to 600 ° C.