Concrete discharging device and mixer truck

Abstract

The concrete discharging device comprises a discharging hopper, a bottom cover driving mechanism and a liquid level detection assembly, the discharging hopper is arranged on the tail portion of the mixer truck and receives concrete sent out by a mixing drum on the mixer truck, the bottom cover driving mechanism comprises a driving piece and a bottom sealing cover, and the liquid level detection assembly is arranged on the bottom sealing cover. The driving part is arranged on the discharge hopper and drives the bottom sealing cover to open or close a discharge port of the discharge hopper, the liquid level detection assembly is arranged at the tail of the mixer truck and located above a feed port of the discharge hopper, and the liquid level detection assembly is used for detecting the liquid level of concrete in the discharge hopper under the condition that the discharge port is closed. The single-time unloading volume can be determined according to the concrete liquid level, so that the total unloading volume can be determined by counting multiple detection data, and compared with the prior art, the method has the advantages of smaller obvious error, simplicity in operation and low implementation difficulty, can be applied to a fuel vehicle, and can also be applied to a concrete truck. And the system can also be effectively applied to new energy products such as pure electricity and hybrid power.

Description

Technical Field

[0001] The utility model belongs to the technical field of mixer trucks, and in particular relates to a concrete unloading device and a mixer truck. Background Art

[0002] A mixer truck is a special vehicle used to transport concrete and keep the mixing drum rotating during transportation to prevent the concrete from solidifying. The unloading system of the mixer truck includes a unloading hopper and a unloading chute at the rear of the mixer truck. When unloading, the concrete passes through the unloading hopper to the unloading chute and is discharged in a specified direction.

[0003] At present, in order to determine the discharge volume of the mixing drum, the existing technology uses the absolute value of the pressure difference between the two high-pressure oil ports of the hydraulic system to determine it. This method has large errors, complex operations, and is difficult to implement. At the same time, with the promotion of new energy related products, pure electric, hybrid and other models do not have hydraulic systems, which makes this method unable to be applied to existing new energy related products. Utility Model Content

[0004] In view of the above-mentioned defects or shortcomings, the utility model provides a concrete unloading device and a mixer truck, aiming to solve the technical problem that the unloading volume is determined by the absolute value of the pressure difference between the two high-pressure oil ports of the hydraulic system, resulting in large errors.

[0005] To achieve the above-mentioned purpose, the first aspect of the utility model provides a concrete unloading device, wherein the concrete unloading device includes a unloading hopper, a bottom cover driving mechanism and a liquid level detection component; the unloading hopper is used to be arranged at the rear of a mixer truck and receive concrete sent from a mixing drum on the mixer truck; the bottom cover driving mechanism includes a driving member and a bottom cover, the driving member is arranged on the unloading hopper and is used to drive the bottom cover to open or close the discharge port of the unloading hopper; the liquid level detection component is arranged at the rear of the mixer truck and is located above the feed port of the unloading hopper, and the liquid level detection component is used to detect the concrete liquid level in the unloading hopper when the discharge port is closed.

[0006] In an embodiment of the utility model, the liquid level detection component includes a mounting bracket and a distance sensor. The mounting bracket is used to be set on the rear crossbeam of the mixer truck, the discharge hopper is placed below the rear crossbeam, and the distance sensor is set on the mounting bracket.

[0007] In an embodiment of the utility model, the mounting bracket includes a bending plate, the bending plate includes a connecting cross plate and a side surrounding vertical plate, the connecting cross plate is used to connect to the rear stage cross beam and extend laterally from the rear stage cross beam, the side surrounding vertical plate is bent downward and extended from one end of the connecting cross plate away from the rear stage cross beam, and the ranging sensor is suspended on the connecting cross plate and is located between the side surrounding vertical plate and the rear stage cross beam.

[0008] In an embodiment of the utility model, the mounting bracket further comprises two rib plates respectively connected to the side enclosure upright plates, and the two rib plates are respectively arranged on both sides of the distance measuring sensor.

[0009] In the embodiment of the utility model, the distance measuring sensor can be set as an infrared sensor or an ultrasonic sensor.

[0010] In an embodiment of the utility model, the bottom cover includes a cover body and two side mounting plates, the two side mounting plates are respectively arranged on opposite sides of the discharge hopper, and the upper ends of the two side mounting plates are respectively movably hinged on the discharge hopper, the cover body is connected to the lower ends of the two side mounting plates and is used to open or close the discharge port, and the telescopic end of the driving member is arranged downward on the discharge hopper and is drivingly connected to the cover body.

[0011] In an embodiment of the utility model, there are two bottom covers, which are arranged in parallel on the discharge hopper, and the two bottom covers are used to move toward each other when the telescopic end of the driving member is extended and driven, so that the two bottom covers can be assembled to close the discharge port.

[0012] In an embodiment of the utility model, the bottom cover driving mechanism also includes a connecting rod, the two ends of which are movably hinged to the side mounting plates located on the same side of the two bottom covers respectively, one of the bottom covers is connected to the telescopic end of the driving member, and can drive the other bottom cover to move towards or away from each other through the connecting rod under the drive of the driving member.

[0013] In an embodiment of the utility model, the bottom cover driving mechanism also includes a stop limiter provided on the discharge hopper, and the stop limiter is used to limit the opening position of the bottom cover; and / or, the concrete unloading device also includes a discharge chute with adjustable direction provided below the discharge hopper.

[0014] To achieve the above-mentioned object, the second aspect of the utility model provides a mixer truck, wherein the mixer truck comprises a vehicle body, a mixing drum arranged on the vehicle body, and the concrete unloading device according to the above-mentioned method.

[0015] Through the above technical solution, the concrete unloading device provided by the embodiment of the utility model has the following beneficial effects:

[0016] When the above concrete unloading device is used, since a bottom cover driving mechanism and a liquid level detection assembly are additionally provided, the driving member of the bottom cover driving mechanism can drive the bottom cover to open or close the discharge port of the unloading hopper. The liquid level detection assembly is located above the feed port of the unloading hopper and is used to detect the concrete liquid level in the unloading hopper when the discharge port is closed. Therefore, when the mixing drum is unloading, the driving member can be controlled to drive the bottom cover to close the discharge port first, and then the concrete liquid level in the unloading hopper can be detected through the liquid level detection assembly during the unloading process. Since the single unloading volume of concrete can be determined according to the concrete liquid level, the concrete level can be detected according to the liquid level of the concrete. When the concrete liquid level detected by the liquid level detection component reaches the preset single unloading volume, the mixing drum can be controlled to stop unloading, and the driving part can be controlled to drive the bottom cover to open the discharge port to complete the continued unloading of concrete in the unloading hopper. The above unloading action is repeated multiple times, and the total unloading volume can be determined by statistics of multiple detection data. Compared with the method of determining the unloading volume by the absolute value of the pressure difference between the two high-pressure oil ports of the hydraulic system in the prior art, the error is obviously smaller, the operation is simple, and the implementation difficulty is small. At the same time, it can not only be applied to fuel vehicles, but also can be effectively applied to pure electric, hybrid and other new energy products.

[0017] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the embodiments of the present utility model and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present utility model, but do not constitute a limitation on the embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0019] Figure 1 This is a schematic structural diagram of a mixer truck according to an embodiment of the utility model;

[0020] Figure 2 It is a structural schematic diagram of a concrete unloading device according to an embodiment of the utility model;

[0021] Figure 3 yes Figure 2 Schematic diagram of the enlarged structure at A in FIG.

[0022] Figure 4 It is a structural schematic diagram of a liquid level detection assembly installed on a backstage crossbeam according to an embodiment of the utility model;

[0023] Figure 5 yes Figure 4 Schematic diagram of the enlarged structure at B in FIG.

[0024] Figure 6 It is a structural schematic diagram of the bottom cover driving mechanism closing the discharge port according to one embodiment of the utility model;

[0025] Figure 7 It is a structural schematic diagram of the bottom cover driving mechanism opening the discharge port according to one embodiment of the utility model.

[0026] Description of Reference Numerals

[0027] 100 Discharge hopper 101 Feed port

[0028] 200 bottom cover driving mechanism 210 driving member

[0029] 220 bottom cover 221 cover body

[0030] 222 side plate 230 connecting rod

[0031] 240 Stop limiter 300 Liquid level detection component

[0032] 310 Mounting bracket 311 Bending plate

[0033] 312 connecting horizontal plate 313 side wall vertical plate

[0034] 314 Rib plate 320 Distance sensor

[0035] 400 Discharge chute 500 Mixing drum

[0036] 600 Backstage 610 Backstage Beam DETAILED DESCRIPTION

[0037] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0038] The concrete unloading device and the mixer truck of the present utility model will be described below with reference to the accompanying drawings.

[0039] like Figure 1 and Figure 2 As shown, the utility model provides a concrete unloading device, wherein the concrete unloading device comprises:

[0040] The discharge hopper 100 is arranged at the rear of the mixer truck and receives the concrete delivered from the mixing drum 500 on the mixer truck;

[0041] The bottom cover driving mechanism 200 includes a driving member 210 and a bottom cover 220. The driving member 210 is disposed on the discharge hopper 100 and is used to drive the bottom cover 220 to open or close the discharge port of the discharge hopper 100.

[0042] The liquid level detection assembly 300 is arranged at the rear of the mixer truck and is located above the feed port 101 of the discharge hopper 100 , and the liquid level detection assembly 300 is used to detect the concrete liquid level in the discharge hopper 100 when the discharge port is closed.

[0043] When the above-mentioned concrete unloading device is used, due to the additional bottom cover driving mechanism 200 and the liquid level detection assembly 300, the driving member 210 of the bottom cover driving mechanism 200 can drive the bottom cover 220 to open or close the discharge port of the unloading hopper 100, and the liquid level detection assembly 300 is located above the feed port 101 of the unloading hopper 100, and is used to detect the concrete liquid level in the unloading hopper 100 when the discharge port is closed. Therefore, when the mixing drum 500 is unloading, the driving member 210 can be controlled to drive the bottom cover 220 to close the discharge port, and then the concrete liquid level in the unloading hopper 100 can be detected by the liquid level detection assembly 300 during the unloading process. Since the concrete liquid level can be determined The single unloading volume of concrete, so that when the concrete liquid level detected by the liquid level detection component 300 reaches the preset single unloading volume, the mixing drum 500 can be controlled to stop unloading, and the driving member 210 can be controlled to drive the bottom cover 220 to open the discharge port to complete the continued unloading of the concrete in the unloading hopper 100. The above unloading action is repeated multiple times, and the total unloading volume can be determined by statistics of multiple detection data. Compared with the method of determining the unloading volume by the absolute value of the pressure difference between the two high-pressure oil ports of the hydraulic system in the prior art, the error is obviously smaller, the operation is simple, and the implementation difficulty is small. At the same time, it can not only be applied to fuel vehicles, but also can be effectively applied to pure electric, hybrid and other new energy products.

[0044] Specifically, the shape of the discharge hopper 100 can be regular, and a volume calculation formula for the concrete accumulated in the discharge hopper 100 is pre-stored. In the volume calculation formula, except for the concrete liquid level which needs to be detected by the liquid level detection component 300, the other parameters are all known, so that the volume calculation formula can be calculated by substituting the detection data of the liquid level detection component 300 into the volume calculation formula during a single discharge. Of course, the shape of the discharge hopper 100 can also be irregular, but a query table of concrete liquid level-concrete accumulation volume can be pre-established to query the concrete accumulation volume according to the detected concrete liquid level.

[0045] See also Figure 2 and Figure 3In the embodiment of the utility model, the liquid level detection assembly 300 includes a mounting bracket 310 and a distance sensor 320. The mounting bracket 310 is used to be arranged on the rear cross beam 610 of the mixer truck, the discharge hopper 100 is placed below the rear cross beam 610, and the distance sensor 320 is arranged on the mounting bracket 310. The liquid level detection assembly 300 is directly arranged on the rear cross beam 610 located above the discharge hopper 100, so that the distance sensor 320 can emit vertical detection rays or light waves toward the concrete liquid surface of the discharge hopper 100 without adding another stand. In addition, the addition of the mounting bracket 310 in the liquid level detection assembly 300 can facilitate the installation of the distance sensor 320 on the rear cross beam 610.

[0046] Furthermore, if Figure 4 As shown, the backstage 600 of the mixer truck includes a left platform, a right platform, and a backstage crossbeam 610 connecting the left platform and the right platform, and the discharge hopper 100 is placed between the left platform and the right platform and under the backstage crossbeam 610. In addition, the mounting bracket 310 can be detachably connected to the backstage crossbeam 610, and the distance measuring sensor 320 can also be detachably connected to the mounting bracket 310.

[0047] See also Figures 2 to 5 In the embodiment of the utility model, the mounting bracket 310 includes a bending plate 311, and the bending plate 311 includes a connecting horizontal plate 312 and a side surrounding vertical plate 313. The connecting horizontal plate 312 is used to connect with the backstage cross beam 610 and extend horizontally from the backstage cross beam 610. The side surrounding vertical plate 313 is bent downward and extended from one end of the connecting horizontal plate 312 away from the backstage cross beam 610. The distance sensor 320 is suspended and installed on the connecting horizontal plate 312 and is located between the side surrounding vertical plate 313 and the backstage cross beam 610. The addition of the bending plate 311 not only realizes the suspension installation of the distance sensor 320, but also the side surrounding vertical plate 313 and the backstage cross beam 610 can protect the distance sensor 320 from opposite sides. Of course, the utility model is not limited to this. The bending plate 311 can also be spliced ​​by a horizontal plate and a vertical plate, and is not necessarily limited to an integral bending molding. Specifically, the lateral extension direction of the connecting cross plate 312 at the rear cross beam 610 can be set to extend laterally toward the mixing drum 500 to ensure that the installation position of the distance measuring sensor 320 is closer to the central axis of the discharge hopper 100.

[0048] In the embodiment of the utility model, the mounting bracket 310 further includes two ribs 314 respectively connected to the side enclosure vertical plate 313, and the two ribs 314 are respectively arranged on both sides of the distance sensor 320. The addition of the two ribs 314 can, on the one hand, play a role in reinforcing the bending plate 311, and on the other hand, can further play a role in strengthening the protection of the distance sensor 320 from the other opposite sides. Specifically, the two ribs 314 can be both set as right triangles, and one right-angled side of the right triangle is connected to the connecting horizontal plate 312 as the upper end, and the other right-angled side is connected to the side enclosure vertical plate 313 as the side.

[0049] In the embodiment of the utility model, the distance sensor 320 can be set as an infrared sensor or an ultrasonic sensor. The infrared sensor measures the distance between the concrete liquid surface and the infrared sensor by emitting infrared rays and receiving reflected infrared rays; the ultrasonic sensor measures the distance between the concrete liquid surface and the ultrasonic sensor by emitting ultrasonic waves and receiving echoes, and the concrete liquid level accumulated in the discharge hopper 100 can be determined based on the distance measurement of the two. Of course, the utility model is not limited to this, and the distance sensor 320 can also be selected from other suitable laser sensors or acoustic wave sensors.

[0050] See also Figure 2 , Figure 6 and Figure 7 In the embodiment of the utility model, the bottom cover 220 includes a cover body 221 and two side mounting plates 222. The two side mounting plates 222 are arranged on opposite sides of the discharge hopper 100, and the upper ends of the two side mounting plates 222 are respectively hinged to the discharge hopper 100. The cover body 221 is connected to the lower ends of the two side mounting plates 222 and is used to open or close the discharge port. The telescopic end of the driving member 210 is arranged downward on the discharge hopper 100 and is drivingly connected to the cover body 221. Both ends of the cover body 221 are provided with side mounting plates 222 hinged to the discharge hopper 100, so as to ensure the installation stability of the bottom cover 220 on the discharge hopper 100, and when the telescopic end of the driving member 210 is extended, the cover body 221 can be driven to move toward the discharge port until the discharge port is completely closed; when the telescopic end of the driving member 210 is retracted, the cover body 221 can be driven to move away from the discharge port until the discharge port is completely opened. Specifically, the driving member 210 can be configured as a telescopic oil cylinder or a telescopic electric cylinder.

[0051] In the embodiment of the utility model, the number of the bottom cover 220 can be two, and the two bottom covers 220 are arranged in parallel on the discharge hopper 100, and the two bottom covers 220 are used to move towards each other when the telescopic end of the driving member 210 is extended and driven, so that the two bottom covers 220 can be assembled to close the discharge port. One discharge port is set as two bottom covers 220 to be assembled and closed, so that the size of a single bottom cover 220 can be reduced, and when opening and closing, the rotation angle of a single bottom cover 220 can also be reduced to reduce the demand for design space. Furthermore, the two bottom covers 220 are also used to move away from each other when the telescopic end of the driving member 210 is retracted and driven, so that the two bottom covers 220 can be separated to open the discharge port.

[0052] like Figure 6 and Figure 7 As shown, in the embodiment of the utility model, the bottom cover driving mechanism 200 also includes a connecting rod 230, and the two ends of the connecting rod 230 are respectively and one-to-one correspondingly movably hinged with the side mounting plates 222 located on the same side of the two bottom covers 220, one of the bottom covers 220 is connected to the telescopic end of the driving member 210, and can drive the other bottom cover 220 to move towards or away from each other through the connecting rod 230 under the drive of the driving member 210. By adding the connecting rod 230, the two bottom covers 220 can share the same driving member 210 for driving, reducing the number of driving members 210, thereby achieving the purpose of saving manufacturing costs. Of course, the utility model is not limited to this. On the basis of not adding the connecting rod 230, the number of driving members 210 is set to two, and the two driving members 210 are respectively set to correspond to the two bottom covers 220.

[0053] It should be noted that the structures of the side mounting plates 222 of the two bottom covers 220 may be different. Specifically, when the two bottom covers 220 are assembled to close the discharge port, the side mounting plates 222 arranged on the same side of the two bottom covers 220 are arranged at the same height at the hinged mounting points on the discharge hopper 100. The first end of the connecting rod 230 is hinged to the side mounting plate 222 of the bottom cover 220 connected to the telescopic end of the driving member 210, and the first hinge point of the first end on the side mounting plate 222 is lower than the side mounting plate 222. The second end of the connecting rod 230 is hinged on the side plate 222 of the bottom cover 220 which is arranged away from the driving member 210, and the second hinge point of the second end on the side plate 222 is arranged higher than the hinge point of the side half, and the connection line between the hinge point on the side plate 222 with the first hinge point and the first hinge point and the connection line between the hinge point on the side plate 222 with the second hinge point and the second hinge point are equal in distance and parallel in direction.

[0054] In the embodiment of the utility model, the bottom cover driving mechanism 200 also includes a stopper 240 provided on the discharge hopper 100, and the stopper 240 is used to limit the opening position of the bottom cover 220. The addition of the stopper 240 can ensure the stability of the opening position of the bottom cover 220, and further ensure the stability of the subsequent closing position. Specifically, the stopper 240 can be a stopper block or a proximity switch, and the stopper 240 is arranged on the same side as the driving member 210. When the bottom cover 220 connected to the driving member 210 rotates to the position where the discharge port is fully opened, the stopper block abuts against the cover body 221 of the bottom cover 220, or the proximity switch triggers an in-position signal, and the driving member 210 stops retracting and driving.

[0055] Please see again Figure 2 In the embodiment of the utility model, the concrete unloading device further comprises a discharge chute 400 which is arranged below the discharge hopper 100 in an adjustable direction. That is, after the bottom cover 220 of the discharge hopper 100 is opened, the concrete in the discharge hopper 100 can be discharged through the discharge chute 400, and the direction of the discharge chute 400 is adjustable, so it is convenient to achieve docking at any position.

[0056] In addition, if Figure 1 As shown, the utility model also provides a mixer truck, wherein the mixer truck comprises a vehicle body, a mixing drum 500 arranged on the vehicle body, and the concrete unloading device according to the above. Since the mixer truck adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0057] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0060] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A concrete unloading device, characterized in that: The concrete unloading device comprises: A discharge hopper (100) is arranged at the rear of the mixer truck and receives concrete discharged from the mixing drum (500) on the mixer truck; A bottom cover driving mechanism (200), comprising a driving member (210) and a bottom cover (220), wherein the driving member (210) is disposed on the discharge hopper (100) and is used to drive the bottom cover (220) to open or close the discharge port of the discharge hopper (100); A liquid level detection component (300) is arranged at the rear of the mixer truck and is located above the feed port (101) of the discharge hopper (100), and the liquid level detection component (300) is used to detect the concrete liquid level in the discharge hopper (100) when the discharge port is closed.

2. The concrete unloading device according to claim 1, characterized in that: The liquid level detection assembly (300) comprises a mounting bracket (310) and a distance measuring sensor (320); the mounting bracket (310) is used to be arranged on a rear crossbeam (610) of the mixer truck; the discharge hopper (100) is placed below the rear crossbeam (610); and the distance measuring sensor (320) is arranged on the mounting bracket (310).

3. The concrete unloading device according to claim 2, characterized in that: The mounting bracket (310) includes a bending plate (311), and the bending plate (311) includes a connecting transverse plate (312) and a side enclosure vertical plate (313). The connecting transverse plate (312) is used to connect to the rear stage cross beam (610) and extend laterally from the rear stage cross beam (610). The side enclosure vertical plate (313) is bent downward and extended from one end of the connecting transverse plate (312) away from the rear stage cross beam (610). The distance measuring sensor (320) is suspended on the connecting transverse plate (312) and is located between the side enclosure vertical plate (313) and the rear stage cross beam (610).

4. The concrete unloading device according to claim 3, characterized in that: The mounting bracket (310) further comprises two rib plates (314) respectively connected to the side enclosure upright plates (313), and the two rib plates (314) are respectively arranged on both sides of the distance measuring sensor (320).

5. The concrete unloading device according to claim 2, characterized in that: The distance measuring sensor (320) can be set as an infrared sensor or an ultrasonic sensor.

6. The concrete unloading device according to any one of claims 1 to 5, characterized in that: The bottom cover (220) includes a cover body (221) and two side mounting plates (222), the two side mounting plates (222) are respectively arranged on opposite sides of the discharge hopper (100), and the upper ends of the two side mounting plates (222) are respectively movably hinged to the discharge hopper (100), the cover body (221) is connected to the lower ends of the two side mounting plates (222) and is used to open or close the discharge port, and the telescopic end of the driving member (210) is arranged downward on the discharge hopper (100) and is drivingly connected to the cover body (221).

7. The concrete unloading device according to claim 6, characterized in that: There are two bottom covers (220), which are arranged in parallel on the discharge hopper (100), and the two bottom covers (220) are used to move towards each other when the telescopic end of the driving member (210) is extended and driven, so that the two bottom covers (220) can be assembled to close the discharge port.

8. The concrete unloading device according to claim 7, characterized in that: The bottom cover driving mechanism (200) further comprises a connecting rod (230), the two ends of which are respectively and movably hingedly connected to the side mounting plates (222) located on the same side of the two bottom covers (220) in a one-to-one correspondence, one of the bottom covers (220) being connected to the telescopic end of the driving member (210), and can drive the other bottom cover (220) to move towards or away from each other through the connecting rod (230) under the drive of the driving member (210).

9. The concrete discharge device according to any one of claims 1 to 5, characterized in that: The bottom cover driving mechanism (200) further comprises a stopper (240) provided on the discharge hopper (100), the stopper (240) being used to limit the opening position of the bottom cover (220); and / or the concrete discharge device further comprises a discharge chute (400) which is provided below the discharge hopper (100) in a direction-adjustable manner.

10. A mixer truck, characterized in that: The mixer truck comprises a vehicle body, a mixing drum (500) arranged on the vehicle body, and a concrete unloading device according to any one of claims 1 to 9.

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