阅读说明：本技术 建筑工程用沥青铺设装置 (Asphalt laying device for construction engineering ) 是由 叶延森 于 2020-07-27 设计创作，主要内容包括：本发明涉及沥青铺设设备技术领域,更具体地说,涉及一种建筑工程用沥青铺设装置,包括沥青存储罐、机架、转向轮机构、行走轮机构、联动机构、搅拌机构和沥青喷涂机构,所述搅拌机构的下端密封转动配合在所述沥青存储罐内部的中间；所述沥青存储罐固定连接在所述机架上；所述转向轮机构活动连接在所述机架前端的中间；所述行走轮机构活动连接在所述机架后端的两侧；所述行走轮机构传动连接所述联动机构的下端；所述联动机构的中部滑动配合连接在所述搅拌机构的中部,并传动连接所述搅拌机构。本发明中的搅拌机构可以在行走轮机构和联动机构的配合下进行搅拌工作,无需单独设置电机,节能降耗,稳定性好。(The invention relates to the technical field of asphalt paving equipment, in particular to an asphalt paving device for constructional engineering, which comprises an asphalt storage tank, a rack, a steering wheel mechanism, a traveling wheel mechanism, a linkage mechanism, a stirring mechanism and an asphalt spraying mechanism, wherein the lower end of the stirring mechanism is hermetically and rotationally matched in the middle of the interior of the asphalt storage tank; the asphalt storage tank is fixedly connected to the rack; the steering wheel mechanism is movably connected to the middle of the front end of the rack; the walking wheel mechanism is movably connected to two sides of the rear end of the rack; the traveling wheel mechanism is in transmission connection with the lower end of the linkage mechanism; the middle part of the linkage mechanism is connected with the middle part of the stirring mechanism in a sliding fit mode and is connected with the stirring mechanism in a transmission mode. The stirring mechanism can perform stirring work under the coordination of the travelling wheel mechanism and the linkage mechanism, a motor is not required to be arranged independently, energy is saved, consumption is reduced, and stability is good.)

1. Asphalt paving device for building engineering, including pitch storage jar (1), frame (2), turn to wheel mechanism (3), walking wheel mechanism (4), link gear (5), rabbling mechanism (6) and pitch spraying mechanism (7), its characterized in that: the lower end of the stirring mechanism (6) is in sealed rotation fit with the middle inside the asphalt storage tank (1); the asphalt storage tank (1) is fixedly connected to the rack (2); the steering wheel mechanism (3) is movably connected to the middle of the front end of the rack (2); the walking wheel mechanism (4) is movably connected to two sides of the rear end of the rack (2); the traveling wheel mechanism (4) is in transmission connection with the lower end of the linkage mechanism (5); the middle part of the linkage mechanism (5) is connected to the middle part of the stirring mechanism (6) in a sliding fit manner and is in transmission connection with the stirring mechanism (6); the upper end of the linkage mechanism (5) is connected to the top end of the asphalt storage tank (1); the asphalt spraying mechanism (7) is connected to the rack (2); the asphalt spraying mechanism (7) is fixedly connected and communicated with the asphalt storage tank (1).

2. The asphalt paving device for construction engineering according to claim 1, characterized in that: the asphalt storage tank (1) comprises a circular tank body (101) with an open top surface, a tank body supporting ring (102) and a supporting column (103); the circular tank body (101) is fixedly connected to the middle of the tank body supporting ring (102); four sides of the tank body supporting ring (102) are uniformly and fixedly connected with a supporting column (103) in a surrounding manner; the lower ends of the four support columns (103) are fixedly connected to the rack (2) through bolts respectively.

3. The asphalt paving device for construction engineering according to claim 2, characterized in that: and the outer wall of the circular tank body (101) is fixedly connected with an electric heating ring.

4. The asphalt paving device for construction engineering according to claim 1, characterized in that: the walking wheel mechanism (4) comprises a walking wheel (401), a wheel shaft (402) and a friction transmission wheel (403); two ends of the wheel shaft (402) are respectively and rotatably matched with two sides of the rear end of the rack (2); two ends of the wheel shaft (402) are respectively and fixedly connected with a travelling wheel (401); the friction transmission wheel (403) is connected to the wheel shaft (402), and the friction transmission wheel (403) is driven by the wheel shaft (402) to rotate; the friction transmission wheel (403) is vertically connected with the linkage mechanism (5) in a friction transmission manner.

5. The asphalt paving device for construction engineering according to claim 4, characterized in that: the friction transmission wheel (403) comprises a transmission wheel body (403A), a sliding block (403B), a first screw (403C) and an adjusting rotating wheel (403D); the transmission wheel body (403A) is in sliding fit with the wheel shaft (402); a guide chute is arranged on the wheel shaft (402); the inner end of the driving wheel body (403A) is fixedly connected with the sliding block (403B); the sliding block (403B) is in sliding fit in a guide sliding groove of the wheel shaft (402); one end of the first screw (403C) is connected to the inner end of the guide chute in a rotating fit manner; the other end of the first screw (403C) is fixedly connected with the adjusting rotating wheel (403D); the adjustment wheel (403D) is located at the outer end of the axle (402); the transmission wheel body (403A) is in vertical friction transmission connection with the linkage mechanism (5).

6. The asphalt paving device for construction engineering according to claim 5, characterized in that: the linkage mechanism (5) comprises a friction linkage wheel (501), a linkage shaft (502), a lifting connecting plate (503), a second screw rod (504), an adjusting rotating block (505), a tensioning spring (506) and a connecting base (507); the friction linkage wheel (501) is in vertical friction transmission connection with the transmission wheel body (403A); the friction linkage wheel (501) is fixedly connected to the lower end of the linkage shaft (502); the middle part of the linkage shaft (502) is in sliding fit with the stirring mechanism (6), and the linkage shaft (502) is in transmission connection with the stirring mechanism (6); the upper end of the linkage shaft (502) is in sliding fit with the tipping seat (507); the top end of the linkage shaft (502) is connected to the lifting yoke plate (503) in a rotating fit manner; two ends of the lifting yoke plate (503) are respectively matched on a second screw rod (504) through threads; the top ends of the two second screw rods (504) are respectively and fixedly connected with an adjusting rotating block (505); the bottom ends of the two second screw rods (504) are respectively and rotatably matched with the two ends of the connecting base (507); the tipping base (507) is fixedly connected to the top end of the asphalt storage tank (1) through a bolt; a tension spring (506) is sleeved on the second screw rod (504); and two ends of the tensioning spring (506) are respectively and fixedly connected with the lifting yoke plate (503) and the connecting base (507).

7. The asphalt paving device for construction engineering according to claim 6, characterized in that: the stirring mechanism (6) comprises a linkage rotating pipe (601), a rotating seat (602), a stirring roller (603), a bottom scraper (604) and a side scraper (605); the bottom end of the linkage rotating pipe (601) is in sealed rotating fit with a circular through hole in the middle of the bottom surface of the asphalt storage tank (1); the linkage shaft (502) is in sliding fit in the linkage rotating pipe (601); a rib is fixedly connected to the inner side of the linkage rotating pipe (601), and the rib is in sliding fit with a groove formed in the linkage shaft (502); the bottom end of the linkage rotating pipe (601) is fixedly connected with the middle of the bottom scraper (604); the bottom scraper (604) is in sliding fit with the bottom surface of the asphalt storage tank (1); two ends of the bottom scraper (604) are respectively fixedly connected with a side scraper (605); two side scrapers (605) are slidably fitted on the side inside the asphalt storage tank (1); an upper rotary seat and a lower rotary seat (602) are fixedly connected to the linkage rotary pipe (601); a plurality of stirring rollers (603) are fixedly connected to the outer sides of the rotating seats (602) in a surrounding manner; a plurality of stirring rollers (603) are rotatably fitted inside the asphalt storage tank (1).

8. The asphalt paving device for construction engineering according to claim 7, characterized in that: the asphalt spraying mechanism (7) comprises a pumping pipe (701), a heat-preservation asphalt pump (702), an output pipe (703), a delivery pipe (704) and a fixed spraying pipe (705); one end of the pumping pipe (701) is fixedly connected with the interior of the asphalt storage tank (1), and the other end of the pumping pipe (701) is fixedly connected with one end of the heat-preservation asphalt pump (702); the heat-preservation asphalt pump (702) is fixedly connected to the rack (2); the other end of the heat-preservation asphalt pump (702) is fixedly connected with an output pipe (703); the lower end of the output pipe (703) is fixedly connected and communicated with the fixed spraying pipe (705) through a delivery pipe (704); the middle part of the conveying pipe (704) is fixedly connected to the rack (2).

9. The asphalt paving device for construction engineering according to claim 8, characterized in that: the asphalt spraying mechanism (7) further comprises a connecting pipe (706) with a control valve, a metal hose (707), a movable spraying pipe (708), a displacement pipe frame (709), a T-shaped supporting block (710), a linkage rod (711), a push-pull connecting rod (712), a rotating wheel (713) and a short shaft (714); the output pipe (703) is a three-way pipe, and three pipe orifices of the output pipe (703) are respectively fixedly connected and communicated with the delivery pipe (704), the outlet of the heat-preservation asphalt pump (702) and the connecting pipe (706); the other end of the connecting pipe (706) is fixedly connected and communicated with the metal hose (707); the other end of the metal hose (707) is fixedly connected and communicated with the movable spraying pipe (708); the movable spraying pipe (708) is fixedly connected to the displacement pipe frame (709); the top surface of the displacement pipe frame (709) is in sliding fit with the bottom surface of the rack (2); the inner end of the displacement pipe frame (709) is in sliding fit with a vertical plate of the T-shaped support block (710) through a rectangular sliding groove; the transverse plate of the T-shaped support block (710) is in sliding fit with the bottom surface of the displacement pipe frame (709); the inner end of the displacement pipe frame (709) is fixedly connected with the linkage rod (711); the linkage rod (711) is rotationally matched with one section of the push-pull connecting rod (712); the other end of the push-pull connecting rod (712) is rotatably matched at the eccentric position of the rotating wheel (713); the rotating wheel (713) is rotatably matched at the lower end of the rack (2) through a short shaft (714); the friction linkage wheel (501) is in friction transmission connection with the rotating wheel (713).

10. The asphalt paving device for construction engineering according to claim 9, characterized in that: the movable spray pipe (708) and the fixed spray pipe (705) have the same structure; the fixed spraying pipe (705) comprises a transverse pipe (705A), a pressurizing spray head (705B) and a spraying control piece; the transverse pipe (705A) is fixedly connected and communicated with the conveying pipe (704); the lower end of the transverse pipe (705A) is uniformly and fixedly connected and communicated with a plurality of pressurizing nozzles (705B); both ends of the transverse pipe (705A) are respectively and movably connected with a spraying control piece; the spray control piece comprises a sliding block (705C), a transverse screw (705D) and a screwing block (705E); the sliding block (705C) is in sealing sliding fit in the transverse pipe (705A); the convex rib on the inner side of the transverse pipe (705A) is in sealed sliding fit in the groove of the sliding block (705C); the sliding block (705C) is in threaded fit with the transverse screw (705D); the transverse screw rod (705D) is in sealed rotating fit with an end cover at the outer end of the transverse pipe (705A); the outer end of the transverse screw rod (705D) is fixedly connected with a screwing block (705E).

Technical Field

The invention relates to the technical field of asphalt paving equipment, in particular to an asphalt paving device for constructional engineering.

Background

The asphalt is a black-brown complex mixture composed of hydrocarbons with different molecular weights and nonmetal derivatives thereof, is one of high-viscosity organic liquids, has a black surface, is soluble in carbon disulfide, and is also a common material in the road construction process. Road surface permeable course and viscous layer generally adopt the asphalt distribution truck to spray and lay one deck emulsified asphalt in road construction, this just need utilize pitch laying device to lay pitch, because the viscosity of pitch is great, consequently need stir it, prevent that it from taking place to solidify, but the agitated vessel majority among the prior art adopts solitary motor to control, and the motor operation is unstable, and consumes the energy more, and occupation space is great.

Disclosure of Invention

The invention aims to provide an asphalt laying device for construction engineering, which can effectively solve the problems in the prior art; the stirring mechanism can perform stirring work under the coordination of the travelling wheel mechanism and the linkage mechanism, a motor is not required to be arranged independently, energy is saved, consumption is reduced, and stability is good.

In order to achieve the purpose, the application provides an asphalt paving device for construction engineering, which comprises an asphalt storage tank, a rack, a steering wheel mechanism, a walking wheel mechanism, a linkage mechanism, a stirring mechanism and an asphalt spraying mechanism, wherein the lower end of the stirring mechanism is in sealed running fit with the middle inside the asphalt storage tank; the asphalt storage tank is fixedly connected to the rack; the steering wheel mechanism is movably connected to the middle of the front end of the rack; the walking wheel mechanism is movably connected to two sides of the rear end of the rack; the traveling wheel mechanism is in transmission connection with the lower end of the linkage mechanism; the middle part of the linkage mechanism is connected with the middle part of the stirring mechanism in a sliding fit manner and is in transmission connection with the stirring mechanism; the upper end of the linkage mechanism is connected to the top end of the asphalt storage tank; the asphalt spraying mechanism is connected to the rack; the asphalt spraying mechanism is fixedly connected and communicated with the asphalt storage tank.

Optionally, the asphalt storage tank includes a circular tank body with an open top surface, a tank body supporting ring and a supporting column; the circular tank body is fixedly connected to the middle of the tank body supporting ring; the four sides of the tank body supporting ring are uniformly and fixedly connected with a supporting column in a surrounding manner; the lower ends of the four support columns are fixedly connected to the rack through bolts respectively.

Optionally, the outer wall of the circular tank body is fixedly connected with an electric heating ring.

Optionally, the walking wheel mechanism comprises a walking wheel, a wheel shaft and a friction driving wheel; two ends of the wheel shaft are respectively and rotatably matched with two sides of the rear end of the rack; two ends of the wheel shaft are respectively fixedly connected with a travelling wheel; the friction driving wheel is connected to the wheel shaft and driven by the wheel shaft to rotate; the friction transmission wheel is connected with the linkage mechanism in a vertical friction transmission manner.

Optionally, the friction transmission wheel includes a transmission wheel body, a slider, a first screw and an adjusting wheel; the driving wheel body is in sliding fit with the wheel shaft; the wheel shaft is provided with a guide chute; the inner end of the driving wheel body is fixedly connected with the sliding block; the sliding block is in sliding fit with the guide sliding groove of the wheel shaft; one end of the first screw is connected to the inner end of the guide chute in a rotating fit manner; the other end of the first screw is fixedly connected with the adjusting rotating wheel; the adjusting rotating wheel is positioned at the outer end of the wheel shaft; the transmission wheel body is connected with the linkage mechanism in a vertical friction transmission mode.

Optionally, the linkage mechanism comprises a friction linkage wheel, a linkage shaft, a lifting yoke plate, a second screw, an adjusting rotating block, a tensioning spring and a connecting seat; the friction linkage wheel is in vertical friction transmission connection with the transmission wheel body; the friction linkage wheel is fixedly connected to the lower end of the linkage shaft; the middle part of the linkage shaft is in sliding fit in the stirring mechanism, and the linkage shaft is in transmission connection with the stirring mechanism; the upper end of the linkage shaft is in sliding fit with the tipping base; the top end of the linkage shaft is connected to the lifting yoke plate in a rotating fit manner; two ends of the lifting yoke plate are respectively matched on a second screw rod through threads; the top ends of the two second screw rods are respectively fixedly connected with an adjusting rotating block; the bottom ends of the two second screw rods are respectively and rotatably matched with the two ends of the connecting seat; the tipping base is fixedly connected to the top end of the asphalt storage tank through a bolt; a tensioning spring is sleeved on the second screw rod; and two ends of the tensioning spring are respectively fixedly connected with the lifting yoke plate and the connecting base.

Optionally, the stirring mechanism comprises a linkage rotating pipe, a rotating seat, a stirring roller, a bottom scraper and a side scraper; the bottom end of the linkage rotating pipe is in sealed and rotating fit with a circular through hole in the middle of the bottom surface of the asphalt storage tank; the linkage shaft is in sliding fit with the linkage rotating pipe; the inner side of the linkage rotating pipe is fixedly connected with a convex edge; the rib is in sliding fit with a groove arranged on the linkage shaft; the bottom end of the linkage rotating pipe is fixedly connected with the middle of the bottom scraping plate; the bottom scraper is in sliding fit with the bottom surface of the asphalt storage tank; two ends of the bottom scraper are respectively fixedly connected with a side scraper; two side scrapers are in sliding fit on the side surfaces of the interior of the asphalt storage tank; the linkage rotating pipe is fixedly connected with an upper rotating seat and a lower rotating seat; a plurality of stirring rollers are fixedly connected to the outer sides of the rotating seats in a surrounding manner; many stirring roller normal running fit are in the inboard of pitch storage jar.

Optionally, the asphalt spraying mechanism comprises a pumping pipe, a heat-preservation asphalt pump, an output pipe, a conveying pipe and a fixed spraying pipe; one end of the pumping pipe is fixedly connected with the interior of the asphalt storage tank, and the other end of the pumping pipe is fixedly connected with one end of the heat-preservation asphalt pump; the heat-preservation asphalt pump is fixedly connected to the rack; the other end of the heat-preservation asphalt pump is fixedly connected with an output pipe; the lower end of the output pipe is fixedly connected and communicated with the fixed spraying pipe through a conveying pipe; the middle part of the conveying pipe is fixedly connected to the rack; the fixed spraying pipe is positioned at the lower end of the rack.

Optionally, the asphalt spraying mechanism further comprises a connecting pipe with a control valve, a metal hose, a movable spraying pipe, a displacement pipe frame, a T-shaped support block, a linkage rod, a push-pull connecting rod, a rotating wheel and a short shaft; the output pipe is a three-way pipe, and three pipe orifices of the output pipe are respectively fixedly connected and communicated with the conveying pipe, the outlet of the heat-preservation asphalt pump and the connecting pipe; the other end of the connecting pipe is fixedly connected and communicated with the metal hose; the other end of the metal hose is fixedly connected and communicated with the movable spraying pipe; the movable spraying pipe is fixedly connected to the displacement pipe frame; the top surface of the displacement pipe frame is in sliding fit with the bottom surface of the rack; the inner end of the displacement pipe frame is in sliding fit with a vertical plate of the T-shaped support block through a rectangular sliding groove; a transverse plate of the T-shaped support block is in sliding fit with the bottom surface of the displacement pipe frame; the inner end of the displacement pipe frame is fixedly connected with the linkage rod; the linkage rod is rotationally matched with one section of the push-pull connecting rod; the other end of the push-pull connecting rod is rotatably matched with the eccentric position of the rotating wheel; the rotating wheel is in rotating fit with the lower end of the rack through a short shaft; the friction linkage wheel is in friction transmission connection with the rotating wheel.

Optionally, the movable spray pipe and the fixed spray pipe have the same structure; the fixed spraying pipe comprises a transverse pipe, a pressurizing spray head and a spraying control piece; the transverse pipe is fixedly connected and communicated with the conveying pipe; the lower end of the transverse pipe is uniformly and fixedly connected and communicated with a plurality of pressurizing nozzles; two ends of the transverse pipe are respectively and movably connected with a spraying control piece; the spraying control piece comprises a sliding block, a transverse screw and a screwing block; the sliding block is in sealing sliding fit in the transverse pipe; the convex edge on the inner side of the transverse pipe is in sealed sliding fit in the groove of the sliding block; the sliding block is matched on the transverse screw rod through threads; the transverse screw rod is in sealed and rotating fit with an end cover at the outer end of the transverse pipe; the outer end of the transverse screw is fixedly connected with a screwing block.

The invention provides an asphalt paving device for construction engineering, which has the beneficial effects that:

the stirring mechanism can perform stirring work under the coordination of the travelling wheel mechanism and the linkage mechanism, a motor is not required to be arranged independently, energy is saved, consumption is reduced, and stability is good; the movable spraying pipe and the fixed spraying pipe are arranged in the asphalt spraying mechanism, and the movable spraying pipe can perform supplementary spraying after the fixed spraying pipe is sprayed, so that the spraying and laying effect of asphalt is improved conveniently.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a first general schematic diagram provided in accordance with an embodiment of the present invention;

FIG. 2 is a second overall view provided in accordance with an embodiment of the present invention;

FIG. 3 is a schematic diagram of an asphalt storage tank provided by an embodiment of the present invention;

FIG. 4 is a schematic view of a steering wheel mechanism provided in accordance with an embodiment of the present invention;

FIG. 5 is a schematic view of a travel wheel mechanism provided in an embodiment of the present invention;

FIG. 6 is a schematic view of a friction drive wheel provided in an embodiment of the present invention;

FIG. 7 is a schematic view of a linkage mechanism provided by an embodiment of the present invention;

FIG. 8 is a schematic view of a stirring mechanism provided in an embodiment of the present invention;

FIG. 9 is a first schematic diagram of an asphalt spraying mechanism according to an embodiment of the present invention;

FIG. 10 is a second schematic view of an asphalt spraying mechanism according to an embodiment of the present invention;

FIG. 11 is a schematic view of a stationary spray tube provided in accordance with an embodiment of the present invention;

FIG. 12 is a cross-sectional view of a stationary spray tube provided in accordance with an embodiment of the present invention;

fig. 13 is a schematic view of a rack according to an embodiment of the present invention.

Icon: an asphalt storage tank 1; a circular can body 101; a tank carrier ring 102; a support column 103; a frame 2; a steering wheel mechanism 3; a traveling wheel mechanism 4; a road wheel 401; an axle 402; a friction transmission wheel 403; a driving wheel body 403A; a slider 40311B; a first screw 403C; an adjustment wheel 403D; a link mechanism 5; a friction linkage wheel 501; a linkage shaft 502; a lifting yoke plate 503; a second screw 504; an adjustment rotating block 505; a tension spring 506; a mounting seat 507; a stirring mechanism 6; a linkage rotating pipe 601; a rotary base 602; a stirring roller 603; a bottom scraper 604; a side flight 605; an asphalt spraying mechanism 7; a withdrawal pipe 701; a heat-insulating asphalt pump 702; an output pipe 703; a delivery pipe 704; a fixed spray tube 705; cross tube 705A; a pressure showerhead 705B; a sliding block 705C; the horizontal screw 705D; a screw block 705E; a connecting tube 706; a metal hose 707; a movable spray tube 708; a displacement pipe frame 709; a T-shaped bracket 710; a linkage rod 711; a push-pull link 712; a rotation wheel 713; a short axis 714.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or be indirectly disposed on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, the meaning of a plurality of or a plurality of is two or more unless specifically limited otherwise.

It should be understood that the structures, ratios, sizes, and the like shown in the drawings and described in the specification are only used for understanding and reading the contents disclosed in the specification, and are not used for limiting the conditions that the present application can implement, so the present invention has no technical significance, and any structural modification, ratio relationship change or size adjustment should still fall within the scope of the technical content disclosed in the present application without affecting the efficacy and the achievable purpose of the present application. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present application, and changes or modifications in the relative relationship may be made without substantial technical changes.

The invention is described in further detail below with reference to fig. 1-13.