JP5639567B2 - Return pipe structure of cleaning liquid tank - Google Patents

Description

  The present invention relates to a return pipe structure for a cleaning liquid tank, and more particularly to a return pipe structure for a cleaning liquid tank mounted on a paving machine or the like.

  Generally, when performing asphalt paving work on a road surface, asphalt emulsion is sprayed by an emulsion spraying device mounted on a paving machine as an adhesive between the road surface and the asphalt mixture. At the end of the emulsion spraying, the cleaning liquid for cleaning the emulsion circulation path reaches the emulsion forward path from the cleaning liquid tank via the cleaning liquid path, and then flows from the emulsion return path to the cleaning liquid path via the emulsion sprayer. Return.

  FIG. 9 shows a conventional example of a cleaning liquid tank mounted on a paving machine. As shown in the drawing, one end of an air breather 72 that ventilates the inside and outside of the cleaning liquid tank 71 is connected to the upper part of the cleaning liquid tank 71. The cleaning liquid tank 71 is prevented from being damaged by the expansion and contraction of the liquid.

  A return pipe 73 for cleaning liquid is connected to the vicinity of the air breather 72 in the upper part of the cleaning liquid tank 71. The lower end of the return pipe 73 is positioned higher than the liquid level 70 in the cleaning liquid tank 71. The cleaning liquid in the return pipe 73 is configured to be pushed back into the cleaning liquid tank 71 from the return pipe 73 by air (see, for example, Patent Document 1).

JP 2010-60121 A

  In the above prior art, the return pipe is at a position higher than the liquid level in the cleaning liquid tank, and the cleaning liquid is pushed back into the cleaning liquid tank by the pressure of air. Then, when the cleaning liquid flows into the cleaning liquid tank together with air, the liquid level in the cleaning liquid tank is generated by a strong impact on the liquid level in the cleaning liquid tank due to the forced drop of the cleaning liquid due to the air pressure. As a result, there was a problem that the undulating cleaning liquid was blown out from the air breather.

  As a countermeasure for preventing the blowout, it is conceivable to increase the volume of the cleaning liquid tank itself in order to widen the liquid level in the cleaning liquid tank. However, even with this configuration, it is difficult to expect a stable ripple suppression effect due to fluctuations in the return amount of the cleaning liquid, and the cleaning liquid tank must be enlarged to ensure a large installation space.

  Therefore, without enlarging the cleaning liquid tank, the technical problem to be solved in order to effectively suppress the liquid surface ripple in the cleaning liquid tank and prevent the cleaning liquid from blowing out from the air breather arises. The present invention aims to solve this problem.

The present invention has been proposed to achieve the above object, and the invention according to claim 1 is characterized in that a cleaning liquid return pipe is connected to an upper part of a cleaning liquid tank to which an air breather is attached, and the lower end of the return pipe is In the return pipe structure of the cleaning liquid tank positioned higher than the liquid level in the cleaning liquid tank, the return pipe is provided on the outer side of the inner pipe part where the cleaning liquid in the cleaning liquid pipe is pushed back by air. An outer pipe portion and a flange pipe portion disposed on the upper outer side of the outer pipe portion, and the inner pipe portion is covered with a lower end and is provided on a lower side surface of the inner pipe portion. A plurality of small holes are drilled, and the outer pipe portion has a lower end opened, and a plurality of small holes are drilled in an upper side surface of the outer pipe portion. Providing a return pipe structure of the cleaning liquid tank, wherein the mouth lower end that the air is configured to escape to the outside.

  According to this configuration, since the plurality of small holes are drilled in the lower side surface of the inner pipe portion covered with the lower end, when the cleaning liquid and air flow into the cleaning liquid tank from the inner pipe section, the inner pipe section Ejects from a small hole. Then, most of the jetted cleaning liquid moves along the inner surface of the outer pipe portion and falls into the cleaning liquid tank.

  In addition, since a plurality of small holes are drilled in the upper side surface of the outer pipe portion and the small holes of the outer pipe portion are surrounded by the flange pipe portion, the jetted air flows from the small holes of the outer pipe portion and the lower end of the opening. Dissipate outside. As a result, the cleaning liquid is not pushed down by the air, and the cleaning liquid naturally falls gently toward the liquid surface in the cleaning liquid tank, so that the undulation of the liquid surface is suppressed.

  According to a second aspect of the present invention, the plurality of small holes drilled in the inner pipe portion and the outer pipe portion are respectively arranged in a plurality of rows in the vertical direction, and the small holes in each row are all around the pipe. 2. A return pipe structure for a cleaning liquid tank according to claim 1, wherein the return pipe structure is disposed along a direction.

  According to this configuration, the small holes in the inner pipe portion and the small holes in the outer pipe portion are both arranged in a plurality of rows in the vertical direction and are formed side by side in the entire circumferential direction of each pipe. Therefore, when the cleaning liquid and the air are ejected from the small hole, the cleaning liquid and the air are smoothly spread and diffused outward in the radial direction of the pipe.

  According to a third aspect of the present invention, there is provided the return pipe structure for a cleaning liquid tank according to the first or second aspect, wherein the lower end of the outer pipe portion is positioned in the vicinity of the liquid level of the cleaning liquid tank.

  According to this configuration, since the lower end of the opening of the outer pipe part is close to the liquid level of the cleaning liquid tank, the cleaning liquid from the lower end of the opening of the outer pipe part slowly falls on the liquid level of the cleaning liquid tank.

  According to the first aspect of the present invention, since there is no need to push down the cleaning liquid by air, the liquid surface in the cleaning liquid tank can be suppressed, so that the cleaning liquid can be effectively prevented from being blown out from the air breather. In this case, it is not necessary to enlarge the cleaning liquid tank, and even when the return amount of the cleaning liquid fluctuates greatly, a stable ripple suppressing effect is always obtained. Therefore, the present invention can improve the quality performance of the cleaning liquid tank as compared with the conventional example.

  In the invention described in claim 2, since the cleaning liquid and air are ejected smoothly and smoothly in the radial direction in the small holes, in addition to the effect of the invention described in claim 1, the cleaning liquid is improved while improving the efficiency of air diffusion. Has the merit that the drop to the liquid surface becomes more gradual.

  According to the third aspect of the present invention, the liquid drop of the cleaning liquid tank is dropped with almost no impact. Therefore, in addition to the effect of the first or second aspect of the invention, the undulation of the liquid level is made as much as possible. Can be eliminated.

The whole side view which shows the paving machine carrying the washing | cleaning liquid tank which concerns on this invention. The piping diagram of the emulsion dispersion | spreading apparatus which concerns on this invention. The top view which shows the emulsion piping valve switch box of the emulsion spraying apparatus which concerns on this invention. Sectional drawing of the washing | cleaning liquid tank which concerns on this invention. The top view of the return pipe structure of the washing | cleaning-liquid tank which concerns on this invention. The front view of FIG. AA sectional drawing of FIG. Sectional drawing explaining the fall state of the washing | cleaning liquid in the return pipe structure which concerns on this invention. Sectional drawing which shows the washing | cleaning liquid tank of a prior art example.

  The present invention achieves the object of preventing the cleaning liquid from being blown out of the air breather by preventing the cleaning liquid and the air from flowing in the cleaning liquid tank when the cleaning liquid in the return pipe is pushed back into the cleaning liquid tank with air. Therefore, in the return pipe structure of the cleaning liquid tank, the cleaning liquid return pipe is connected to the upper part of the cleaning liquid tank to which the air breather is attached, and the lower end of the return pipe is positioned higher than the liquid level in the cleaning liquid tank. The return pipe includes an inner pipe portion in which the cleaning liquid in the cleaning liquid pipe is pushed back by air, an outer pipe portion provided outside the inner pipe portion, and a flange pipe portion disposed outside the upper portion of the outer pipe portion. The inner pipe portion has a lower end covered with a plurality of small holes on the lower side surface of the inner pipe portion. The outer pipe portion has a lower end opened, and a plurality of small holes are formed in the upper side surface of the outer pipe portion. Realized by the configuration to escape.

  Hereinafter, a return pipe structure of a cleaning liquid tank according to a preferred embodiment of the present invention will be described with reference to FIGS.

  An asphalt finisher (paving machine) with an emulsion spraying device shown in FIG. 1 mainly includes a front wheel 1a and a rear wheel 1b, a vehicle body 2, an engine 3, a hopper 4 for containing the asphalt mixture, and a bar feeder for carrying out the asphalt mixture in the hopper 4. 5, a spreading screw 6 that sends out the asphalt mixture carried by the bar feeder 5 to the road surface, a screed 7 that spreads the asphalt mixture sent to the road surface 8, and a driver's seat 9.

  An engine room 10 is mounted at the center of the vehicle body 2, and the engine 3 is installed in the engine room 10. A bar feeder 5 is interposed between the hopper 4 and the spreading screw 6, and a screed 7 is supported by the vehicle body 2 behind the spreading screw 6. The screed 2 is divided into right and left and front and rear. It can be stretched.

An emulsion spraying device 21 shown in FIG. 2 includes an emulsion tank 11 for storing asphalt emulsion, an emulsion forward path 12 for sucking in the asphalt emulsion in the emulsion tank 11, and an asphalt emulsion sent from the emulsion tank 11 via the emulsion forward path 12. An emulsion spray bar 13 that distributes a part to a plurality of spray nozzles 13 a and an emulsion return path 14 that returns the asphalt emulsion sent to the emulsion spray bar 13 to the emulsion tank 11 are configured.
The emulsion tank 11 is connected to one end of a left emulsion spray bar 13b and a right emulsion spray bar 13c installed between the left and right rear wheels 1b and the spreading screw 6 via an emulsion forward path 12 that branches to the left and right. Yes. An emulsion filter 15 is provided before the emulsion outgoing path 12 branches, and the asphalt emulsion sent from the emulsion tank 11 is filtered and sent out.

  An emulsion pump 16 is installed before the emulsion outgoing path 12 branches, and the emulsion pump 16 pumps the asphalt emulsion in the emulsion filter 15 to the emulsion sprayer 13. The emulsion sprayer 13 includes a plurality of spray nozzles 13a for spraying the asphalt emulsion on the road surface 8, and one end of the left emulsion sprayer 13b and the right emulsion sprayer 13c, which are constituent elements, are joined together in the middle. To the emulsion return path 14.

  The emulsion circulation path 17 formed by the emulsion forward path 12 and the emulsion return path 14 is provided with an emulsion cleaning device 22 for cleaning the inside of the emulsion circulation path 17 and the like. The emulsion cleaning device 22 includes a cleaning liquid tank 18 for storing the cleaning liquid and a cleaning liquid path 19 for flowing the cleaning liquid into the emulsion circulation path 17.

The cleaning liquid tank 18 stores a cleaning liquid for removing the asphalt emulsion adhering to the emulsion circulation path 17. Further, both ends of the cleaning liquid path 19 are connected to the emulsion circulation path 17, and a cleaning liquid tank 18 is interposed between the cleaning liquid paths 19. One end of the cleaning liquid path 19 is connected to the emulsion forward path 12 before the emulsion filter 15, and the other end of the cleaning liquid path 19 is connected to the emulsion return path 14 (hereinafter referred to as “cleaning liquid piping”) 19. A discharge path 20 that communicates with the outside is connected via a switching valve 29 in front of the cleaning liquid tank 18 so that the flow path direction can be controlled to be switched to the cleaning liquid tank 18 side or the discharge path 20 side by the switching valve 29. It is configured.

  The emulsion forward path 12 is connected to an emulsion supply source and an air supply source (not shown) so as to communicate with each other. The switching valve 29 and the like are built in the emulsion piping valve switch box 32 shown in FIG. 3 provided on the upper left side of the control panel. The emulsion piping valve switch box 32 has a loading switch mode, a spraying switch mode, a washing switch mode or an emulsion extraction mode. A first switch 43 for switching the switch mode, a second switch 44 for switching the emulsion return switch mode, the line cleaning switch mode or the cleaning liquid return switch mode, and a third switch 45 for switching the air switch mode on and off. Is provided. Mono levers 43a, 44a, and 45a for switching operation are installed at the center of each switch 43, 44, and 45, respectively.

  Next, when the washing liquid in the emulsion circulation path 17 is returned to the washing liquid tank 18 by the emulsion washing apparatus 22, the washing liquid return switch mode and the air switch mode are set. As a result, the switching valve 28 b and the switching valve 29 are opened, and the switching valve 31 is opened, so that air flows into the emulsion circulation path 17. Due to the pressure of the air and the pressure of the emulsion pump 16, the cleaning liquid in the emulsion circulation path 17 reaches the emulsion return path 14 via the emulsion forward path 12 through the emulsion sprayer 13 and then flows into the cleaning liquid pipe 19. The cleaning liquid flowing into the cleaning liquid pipe 19 returns to the cleaning liquid tank 18 via the switching valve 28b and the switching valve 29.

  Next, the return pipe structure of the cleaning liquid tank 18 will be described in detail. As shown in FIG. 4, an air breather 52 and a cleaning liquid return pipe 53 are connected to the upper part of the cleaning liquid tank 18 of the paving machine according to the present embodiment in close proximity to each other. The lower end of the return pipe 53 is located higher than the liquid level in the cleaning liquid tank 18 as in the conventional example, but is configured to suppress the ripple phenomenon of the liquid level in the tank due to the cleaning liquid and air. Yes.

  The return pipe 53 includes an inner pipe portion 55 through which the cleaning liquid in the cleaning liquid pipe 19 is pushed back to the cleaning liquid tank 18 by air, an outer pipe portion 56 provided outside the inner pipe portion 55, and an upper portion of the outer pipe portion 56. It is comprised from the flange pipe part 57 arrange | positioned on the outer side, and these pipe parts 55,56,57 are piping on the same core.

The length of the outer pipe part 56 is set longer than the inner pipe part 55 and the flange pipe part 57. Further, the lower end of the outer pipe portion 56 is positioned below the lower end of the inner pipe portion 55 by a predetermined distance, and is set to be close to the liquid surface 50 in the cleaning liquid tank 18.

  5, 6 and 7 show a plan view, a front view and a cross-sectional view, respectively, of the return pipe structure according to the present invention. As shown in FIG. 7, since a plate-like lid member 58 is fixed to the lower end of the inner pipe portion 55, the lower end of the inner pipe portion 55 is closed.

  In addition, a large number of small holes 59 are formed in the lower side surface of the inner pipe portion 55. A large number of small holes 59 are arranged in a number of rows in the vertical direction, and the small holes 59 in each row are arranged along the entire circumferential direction of the inner pipe portion 55. Therefore, the many small holes 59 are opened radially outward from the center of the inner pipe portion 55 in plan view.

  On the other hand, the lower end of the outer pipe portion 56 is formed to be open. Also, as shown in FIG. 6, a large number of small holes 60 are formed in the upper side surface of the outer pipe portion 56. The large number of small holes 60 are arranged in multiple rows in the vertical direction, and the small holes 60 in each row are arranged along the entire circumferential direction of the outer pipe portion 56. Therefore, the large number of small holes 60 are opened radially outward from the center of the outer pipe portion 56 in plan view. Further, as shown in FIG. 4, the small hole 60 of the outer pipe portion 56 is surrounded by the flange pipe portion 57 disposed on the outer side.

  Next, the operation of this embodiment will be described. First, as shown in FIG. 8, the cleaning liquid L and air in the cleaning liquid pipe 19 flow into the cleaning liquid tank 18 from the inner pipe portion 55. At that time, the cleaning liquid L and the air A are ejected to the outside from a large number of small holes 59 provided on the lower side surface of the inner pipe portion 55. Most of the jetted cleaning liquid L slowly falls toward the liquid level 50 in the cleaning liquid tank 18 along the inner surface of the outer pipe portion 56.

  On the other hand, air A is ejected to the outside from a large number of small holes 59 on the lower side surface of the inner pipe portion 55, and then a large number of small holes 60 provided on the upper side surface of the outer pipe portion 56 and the opening of the outer pipe portion 56. Escape smoothly from the bottom to the outside.

  As described above, according to the present invention, since a plurality of small holes are formed in the lower side surface of the inner pipe portion covered with the lower end, when the cleaning liquid and air flow into the cleaning liquid tank from the inner pipe section, It ejects radially outward from a number of small holes in the pipe. Then, most of the sprayed cleaning liquid hits the inner surface of the outer pipe portion, then moves along the inner surface of the outer pipe portion, and slowly falls from the lower end opening toward the liquid surface of the cleaning liquid tank.

  In the present invention, a large number of small holes are formed in the upper side surface of the outer pipe portion having the lower end of the opening, and the small holes of the outer pipe portion are surrounded by the flange pipe portion. Therefore, a part of the air ejected from the small hole in the inner pipe part escapes from the lower end of the opening of the outer pipe part to the outside, but the remaining air is radiated from the numerous small holes provided on the upper side surface of the outer pipe part. Dissipate to the outside.

  As a result, the air pressure is suddenly reduced, and the pressing action against the cleaning liquid is eliminated. For this reason, the occurrence of the ripple phenomenon on the liquid surface in the cleaning liquid tank is effectively suppressed by the air and the cleaning liquid as in the conventional example, so that the cleaning liquid is effectively prevented from being blown out from the air breather. In this case, even when the return amount of the cleaning liquid largely fluctuates, a stable ripple suppressing effect can be always obtained. As a result, the quality performance of the cleaning liquid tank can be remarkably improved.

  Further, the small holes in the inner pipe portion and the small holes in the outer pipe portion are both arranged in a plurality of rows in the vertical direction, and are formed in the radial direction in a plan view side by side along the entire circumferential direction of each pipe. ing. Therefore, when the cleaning liquid and the air are ejected from the small hole, the cleaning liquid and the air are spread and diffused widely outside the pipe in the radial direction. Therefore, the cleaning liquid falls more gently while increasing the efficiency of air diffusion.

  Furthermore, when the lower end of the outer pipe part is positioned in the vicinity of the liquid level of the cleaning liquid tank, when the cleaning liquid naturally falls from the lower end of the outer pipe part toward the liquid surface, the natural fall distance is shortened. The cleaning liquid from the lower end of the opening of the liquid drops gently with almost no impact on the liquid level of the cleaning liquid tank, and as a result, the undulation of the liquid level can be eliminated as much as possible. In this case, since the cleaning liquid tank can be reduced in size, the tank space can be reduced.

  Although some specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. The present invention naturally extends to the modified one.

  As long as the return pipe structure of the cleaning liquid tank according to the present invention is a cleaning liquid tank provided with an air breather and a cleaning liquid return pipe, regardless of the positional relationship and structure of the air breather and the cleaning liquid return pipe or the components of the cleaning liquid, etc. It can be effectively used for a cleaning liquid tank.

18 Cleaning liquid tank 19 Cleaning liquid piping (cleaning liquid path)
50 Liquid level 52 Air breather 53 Return pipe for cleaning liquid 55 Inner pipe part 56 Outer pipe part 57 Flange pipe part 58 Lid member 59,60 Small hole L Cleaning liquid A Air

Claims (3)

In the return pipe structure of the cleaning liquid tank, the return pipe for the cleaning liquid is connected to the upper part of the cleaning liquid tank to which the air breather is attached, and the lower end of the return pipe is positioned higher than the liquid level in the cleaning liquid tank.
The return pipe includes an inner pipe portion in which the cleaning liquid in the cleaning liquid pipe is pushed back by air, an outer pipe portion provided outside the inner pipe portion, and a flange pipe portion disposed outside the upper portion of the outer pipe portion. And
The inner pipe portion has a lower end covered with a plurality of small holes in the lower side surface of the inner pipe portion, and the outer pipe portion has an opening at the lower end and the outer side. A return pipe structure for a cleaning liquid tank, wherein a plurality of small holes are formed in an upper side surface of the pipe portion, and the air escapes to the outside from the small holes of the outer pipe portion and the lower end of the opening.   The plurality of small holes drilled in the inner pipe portion and the outer pipe portion are arranged in a plurality of rows in the vertical direction, and the small holes in each row are arranged along the entire circumferential direction of the pipe. The return pipe structure of the cleaning liquid tank according to claim 1, wherein   3. A return pipe structure for a cleaning liquid tank according to claim 1, wherein a lower end of the outer pipe portion is located in the vicinity of the liquid level of the cleaning liquid tank.