Truck crane and counterweight detection speed limit system and method thereof

Abstract

The present application relates to the technical field of engineering machinery, and discloses a vehicle crane and its counterweight detection speed limit system and method; the vehicle crane includes a chassis, a counterweight and an engine arranged on the chassis, and the counterweight detection speed limit system includes a weight detection component and a control module; the weight detection component is used to detect the weight of the counterweight and send a weight information signal; the control module includes a control unit and an electrical controller, the control unit is electrically connected to the weight detection component, the control unit is used to calculate the maximum allowed vehicle speed according to the weight information signal, and the electrical controller is electrically connected to the control unit, and the electrical controller is used to send a speed limit instruction to the engine according to the maximum allowed vehicle speed. The control unit of the present application obtains the maximum vehicle speed according to the weight information of the counterweight, and the electrical controller limits the engine speed according to the maximum vehicle speed, thereby intelligently controlling the vehicle speed and improving safety.

Description

Technical Field

[0001] The present application belongs to the technical field of engineering machinery, and specifically relates to a truck crane and a counterweight detection speed limit system and method thereof. Background Art

[0002] At present, in the truck crane industry, in order to improve the lifting capacity of the product, some truck cranes with slightly larger tonnage are equipped with counterweights that exceed their own carrying capacity. These additional counterweights will travel with the vehicle when traveling short distances, but after adding additional counterweights to the truck crane, if it still follows the original driving speed, it will exceed the tire's load capacity, posing safety risks such as tire blowouts. In addition, there is currently no solution in the industry to limit the engine speed by detecting the weight of the counterweight and feeding its information back to the engine ECU, which will be a huge safety hazard. Summary of the invention

[0003] The purpose of the present application is to provide a truck crane and a counterweight detection speed limit system and method thereof, which can automatically control the maximum speed of the entire machine for a truck crane equipped with a counterweight, thereby improving safety.

[0004] In order to achieve the above-mentioned object, the present application provides, on one hand, a counterweight detection and speed limiting system for a truck crane, wherein the truck crane comprises a chassis, a counterweight and an engine arranged on the chassis, and the counterweight detection and speed limiting system comprises:

[0005] A weight detection component, used for detecting the weight of the counterweight and sending a weight information signal;

[0006] The control module includes a control unit and an electrical controller, wherein the control unit is electrically connected to the weight detection component, the control unit is used to calculate the maximum allowed vehicle speed based on the weight information signal, and the electrical controller is electrically connected to the control unit, and the electrical controller is used to send a speed limit instruction to the engine based on the maximum allowed vehicle speed.

[0007] In some embodiments, the chassis is provided with a lifting cylinder for lifting the counterweight, and the weight detection assembly includes:

[0008] A hydraulic component, mounted on the outer peripheral wall of the lifting cylinder and connected to the oil circuit of the lifting cylinder;

[0009] A pressure detection component is provided at the bottom of the hydraulic component, and is used to detect the hydraulic oil pressure of the hydraulic component and send a hydraulic oil pressure signal. The pressure detection component is electrically connected to the control unit, and the control unit is further configured as follows:

[0010] receiving a hydraulic oil pressure signal sent by the pressure detection component;

[0011] The weight of the counterweight is calculated according to the hydraulic oil pressure signal and a weight information signal is sent.

[0012] In some embodiments, a locking member is provided between the lifting cylinder and the bottom of the counterweight.

[0013] In some embodiments, the weight detection assembly includes a weight sensor disposed between the counterweight and the frame, the weight sensor being used to detect the weight of the counterweight and send a weight information signal, and the control unit is electrically connected to the weight sensor and is further configured as follows:

[0014] Receive the counterweight weight signal sent by the weight sensor and send the counterweight weight signal.

[0015] A second aspect of the present application provides a counterweight detection speed limiting method for a truck crane, which is applied to the counterweight detection speed limiting system as described above. The counterweight detection speed limiting method comprises the following steps:

[0016] Obtain the weight information of the counterweight and the weight information of the whole machine;

[0017] Calculating the axle loads of the front and rear axles according to the weight information of the counterweight and the weight information of the whole machine;

[0018] Import the axle loads of the front and rear axles into the preset curve diagram and calculate the maximum vehicle speed allowed by the whole machine;

[0019] The engine is controlled to travel at a speed not exceeding a maximum allowed vehicle speed.

[0020] In some embodiments, the axle loads of the front and rear axles can be calculated using the following formula:

[0021] + G 3

[0022] + G 4

[0023] in, G 1 is the axle load carried by the front axle; G is the weight of the counterweight; G 2 is the axle load borne by the rear axle; G 3 is the axle load carried by the front axle (excluding the counterweight); G 4 is the axle load carried by the rear axle (excluding the counterweight); L 1is the distance between the counterweight placement and the front axle; L 2 is the distance between the counterweight placement and the rear axle.

[0024] In some embodiments, the step of importing the axle loads of the front and rear axles into a preset curve diagram and calculating the maximum vehicle speed allowed by the whole machine includes:

[0025] Importing the axle load of the front axle into the preset curve graph to obtain a first vehicle speed corresponding to the axle load of the front axle;

[0026] Importing the axle load of the rear axle into the preset curve graph to obtain a second vehicle speed corresponding to the axle load of the front axle;

[0027] The first vehicle speed and the second vehicle speed are compared, and the minimum value between the two is used as the maximum vehicle speed allowed by the whole machine in the current state.

[0028] In some embodiments, the step of controlling the engine to travel at a speed not exceeding the maximum allowed speed comprises:

[0029] Calculating the maximum speed required by the engine according to the maximum allowed vehicle speed;

[0030] The engine is controlled to rotate at a speed not exceeding the maximum speed.

[0031] In some embodiments, the step of obtaining the preset curve graph includes:

[0032] Obtain the maximum load of the wheel corresponding to multiple different speeds;

[0033] With speed as the horizontal coordinate and the maximum load of the wheel as the vertical coordinate, multiple scattered points are obtained in the coordinate system;

[0034] Draw curves of multiple scattered points in the same coordinate system to obtain a preset curve graph.

[0035] A third aspect of the present application provides a truck crane, comprising a chassis and the counterweight detection and speed limit system as described above, which is arranged on the chassis, a turntable is installed on the chassis, a boom is rotatably installed on the turntable, the control module is installed at the front end of the chassis, and the weight detection component is installed on the turntable.

[0036] In the above technical scheme, the present application adds a control unit and an electrical controller, and electrically connects the control unit, the electrical controller and the weight detection component to communicate. During the driving process of the vehicle, the control unit receives the weight information signal sent by the weight detection component, and calculates the maximum driving speed allowed by the whole machine according to the weight information of the counterweight; and the electrical controller receives the maximum speed signal sent by the control unit, and sends a speed limit instruction to the engine according to the maximum speed signal, thereby achieving the purpose of limiting the speed of the engine, so that the engine speed is within the maximum speed limit range. Through the above technical means, the maximum speed of the whole machine can be intelligently controlled, and the driving safety of the whole machine can be improved.

[0037] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. 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:

[0039] Figure 1 This is a schematic diagram of the structure of the truck crane of this application;

[0040] Figure 2 This is a schematic diagram of the local structure of the truck crane of the present application.

[0041] Description of Reference Numerals

[0042] 10. Chassis; 20. Control module; 30. Counterweight; 31. Locking piece; 40. Boom; 50. Turntable; 70. Balance valve; 80. Pressure sensor; 90. Lifting cylinder. DETAILED DESCRIPTION

[0043] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0044] The following describes the truck crane and its counterweight detection speed limit system and method according to the present application with reference to the accompanying drawings.

[0045] In the prior art, the movable counterweight 30 on the truck crane is usually detected to identify different hoisting conditions in the working state, but the whole machine speed is not limited by detecting the movable counterweight 30, and the whole machine speed limit is usually controlled by the driver. Therefore, in order to fill the technical gap of limiting the whole machine speed by detecting the counterweight 30 on the truck crane, Figure 1 and Figure 2 As shown, the present application provides a counterweight detection and speed limit system for a truck crane. The truck crane includes a chassis 10, a counterweight 30 and an engine arranged on the chassis 10. The counterweight detection and speed limit system includes a weight detection component and a control module 20; the weight detection component is used to detect the weight of the counterweight 30 and send a weight information signal; the control module 20 includes a control unit and an electrical controller, the control unit is electrically connected to the weight detection component, the control unit is used to calculate the maximum allowed vehicle speed according to the weight information signal, the electrical controller is electrically connected to the control unit, and the electrical controller is used to send a speed limit instruction to the engine according to the maximum allowed vehicle speed.

[0046] The present application adds a control unit and an electrical controller, and electrically connects the control unit, the electrical controller, and the weight detection component to communicate. During the driving process of the vehicle, the weight detection component obtains the weight of the counterweight and sends the weight information signal to the control unit. The control unit receives the weight information signal sent by the weight detection component, and calculates the maximum driving speed allowed by the whole machine according to the weight information of the counterweight 30; and the control unit obtains the maximum speed and sends the maximum speed signal to the electrical controller. The electrical controller receives the maximum speed signal sent by the control unit, and sends a speed limit instruction to the engine according to the maximum speed signal, thereby achieving the purpose of limiting the speed of the engine, so that the engine speed is within the maximum speed limit range. Through the above technical means, the maximum speed of the whole machine can be intelligently controlled, and the safety of the whole machine can be improved.

[0047] Furthermore, there are many technical means for obtaining the weight of the counterweight 30. In the first embodiment of the present application, a lifting cylinder 90 for lifting the counterweight 30 is provided on the turntable 50, and the weight detection assembly includes a hydraulic component and a pressure detection component. The hydraulic component is installed on the outer peripheral wall of the lifting cylinder 90 and is connected to the oil circuit of the lifting cylinder 90; the pressure detection component is arranged at the bottom of the hydraulic component, and the pressure detection component is used to detect the hydraulic oil pressure of the hydraulic component and send a hydraulic oil pressure signal to the control unit. The control unit calculates the weight of the counterweight 30 according to the hydraulic oil pressure signal and sends a weight information signal.

[0048] In this embodiment, the pressure detection part is a pressure sensor 80, and the hydraulic component is a balance valve 70. The balance valve 70 is connected to the oil circuit of the lifting cylinder 90. Since the pressure sensor 80 is installed at the bottom of the balance valve 70, when the piston rod of the lifting cylinder 90 moves, the pressure sensor 80 can detect the pressure of the rod chamber and the rodless chamber of the lifting cylinder 90 through the pressure change of the hydraulic oil, and convert the weight of the counterweight 30 according to the inner diameter of the lifting cylinder 90 and the diameter of the piston rod. During the detection process, the pressure sensor detects the hydraulic oil pressure information of the oil circuit where the lifting cylinder 90 is located and sends the hydraulic oil pressure signal to the control unit, and the control unit converts and calculates the weight of the counterweight 30 according to the hydraulic oil pressure signal. In other embodiments, the hydraulic component is not limited to the balance valve 70, and can also be a locking valve connected to the oil circuit of the lifting cylinder 90; the pressure detection part can also be a detection component of other structures.

[0049] In order to achieve locking between the lifting cylinder 90 and the counterweight 30 and prevent the counterweight 30 from being affected in terms of stability due to excessive speed during driving, a locking member 31 is provided between the lifting cylinder 90 and the bottom of the counterweight 30. The locking member 31 may be a locking pin, and when locking, a plurality of locking pins are provided, and the plurality of locking pins sequentially connect the lifting cylinder 90 and the counterweight 30, so that the connection between the lifting cylinder 90 and the counterweight 30 can be made more stable.

[0050] In a second embodiment of the present application, the weight detection component includes a weight sensor arranged between the counterweight 30 and the frame, the weight sensor is used to detect the weight of the counterweight 30 and send a weight information signal, and the control unit is electrically connected to the weight sensor and is further configured to: receive the weight signal of the counterweight 30 sent by the weight sensor and send the weight signal of the counterweight 30.

[0051] In this embodiment, when the counterweight 30 is placed on the vehicle frame, the weight of the counterweight 30 can be directly detected by the weight sensor, and the control unit receives the weight signal of the weight sensor to control the vehicle speed within the maximum speed range.

[0052] A second aspect of the present application provides a counterweight detection speed limiting method for a truck crane, which is applied to the counterweight detection speed limiting system as described above. The counterweight detection speed limiting method comprises the following steps:

[0053] Obtaining weight information of the counterweight 30 and weight information of the entire machine;

[0054] Calculate the axle loads of the front and rear axles according to the weight information of the counterweight 30 and the weight information of the whole machine;

[0055] Import the axle loads of the front and rear axles into the preset curve diagram and calculate the maximum vehicle speed allowed by the whole machine;

[0056] Control the engine to not exceed the maximum permitted speed.

[0057] In the present application, the maximum vehicle speed allowed for the whole machine under the current counterweight 30 is calculated by using the weight information of the counterweight 30. When the whole machine exceeds this maximum vehicle speed, there will be a safety risk; therefore, after obtaining the maximum allowed vehicle speed, the engine speed is controlled so that the speed of the whole machine does not exceed the maximum vehicle speed under the engine speed.

[0058] Furthermore, there is a dedicated position on the frame for placing the counterweight 30. Specifically, a mounting frame can be provided on the chassis 10 of the frame, and the counterweight 30 can be installed on the mounting frame, and the mounting frame is located between the front and rear axles, so that the axle load distributed to the front and rear axles can be obtained by the following calculation formula:

[0059] + G 3

[0060] + G 4

[0061] in, G 1 is the axle load carried by the front axle; G is the weight of the counterweight; G 2 is the axle load borne by the rear axle; G 3 is the axle load carried by the front axle (excluding the counterweight); G 4 is the axle load carried by the rear axle (excluding the counterweight); L 1 is the distance between the position where the counterweight 30 is placed and the front axle; L 2 It is the distance between the position where the counterweight 30 is placed and the rear axle.

[0062] It should be noted that the mounting frame of the counterweight 30 of the present application can be a plate-like structure and is arranged to extend along the width direction of the frame. The bottom of the mounting frame is connected to the telescopic end of the piston rod of the lifting cylinder 90. The counterweight 30 is placed on the side of the mounting frame away from the piston rod, so that the piston rod can push the mounting frame to connect the counterweight 30 to rise or fall together. In addition, the piston rod and the frame, the counterweight 30 and the frame are all connected in a detachable manner; when installing the lifting cylinder 90, the lifting cylinder 90 is installed in the middle, so that the lifting force of the lifting cylinder 90 on the counterweight 30 is concentrated in the middle of the counterweight 30, thereby improving the lifting stability. Support blocks are also provided on both sides of the lifting cylinder 90. When the piston rod of the lifting cylinder 90 is fully retracted, the mounting frame falls on the support blocks to support the mounting frame.

[0063] In some embodiments, the step of importing the axle loads of the front and rear axles into a preset curve diagram and calculating the maximum vehicle speed allowed by the whole machine includes:

[0064] Importing the axle load of the front axle into a preset curve chart, and obtaining a first vehicle speed corresponding to the axle load of the front axle;

[0065] Importing the axle load of the rear axle into a preset curve chart, and obtaining a second vehicle speed corresponding to the axle load of the front axle;

[0066] The first vehicle speed and the second vehicle speed are compared, and the minimum value between the two is used as the maximum vehicle speed allowed by the whole machine in the current state.

[0067] Since the axle loads carried by the front and rear axles are different, the setting of the counterweight 30 also has different axle load pressures on the front and rear axles. By obtaining the vehicle speeds corresponding to the front axle load and the rear axle load, the minimum of the two is taken as the maximum allowable vehicle speed. At this maximum vehicle speed, both the front axle and the rear axle can be driven safely.

[0068] In some embodiments, the step of controlling the engine to travel at a speed not exceeding the maximum allowed speed comprises:

[0069] Calculate the maximum speed required by the engine based on the maximum allowed vehicle speed;

[0070] Control the engine to rotate at a speed not exceeding the maximum speed.

[0071] Specifically, the control module 20 of the chassis 10 is provided with a whole machine weight G 整 (weight excluding the movable counterweight 30) and position parameter information, the axle load carried by the front axle is G 整1 +G 1 The axle load on the rear axle is G 整2 +G 2 ,

[0072] Converted to front and rear tire load: , .

[0073] where n 1 , n 2 The numbers of tires on the front and rear axles respectively.

[0074] Will G 前胎 , G 后胎 Comparing with the preset curve of tire speed change initially imported, we can get G前胎 and G 后胎 The maximum value of the two speeds is taken as the maximum allowable speed in the current state, and the maximum engine speed required at the maximum speed is obtained based on the preset gearbox speed ratio, axle reduction ratio, tire diameter and other parameters.

[0075]

[0076] in, i It is the maximum reduction ratio of the gearbox and the axle reducer; D is the diameter of the wheel, The maximum speed allowed for the whole machine.

[0077] When controlling the engine speed, the electrical controller first sends the maximum vehicle speed information allowed by the entire machine to the instrument panel and reminds the driver. At the same time, the maximum engine speed information corresponding to the maximum allowable vehicle speed is sent to the engine controller. The engine controller limits the maximum engine speed, thereby limiting the maximum vehicle speed of the entire machine.

[0078] In some embodiments, the step of obtaining the preset curve graph includes:

[0079] Obtain the maximum load of the wheel corresponding to multiple different speeds;

[0080] With speed as the horizontal coordinate and the maximum load of the wheel as the vertical coordinate, multiple scattered points are obtained in the coordinate system;

[0081] Draw curves of multiple scattered points in the same coordinate system to obtain a preset curve graph.

[0082] The preset curve graph of the present application is obtained through multiple tests in advance, and the obtained preset curve graph is imported into the control unit in advance. When obtaining the preset curve graph, the tire load capacity corresponding to different vehicle speeds is shown in Table 1 below. Specifically, during the test, the whole machine is driven at different vehicle speeds, the tire load is detected at different vehicle speeds, and a table is recorded.

[0083] Table 1

[0084]

[0085] It can be seen from the above table that the greater the speed, the smaller the load that the tire can bear. Therefore, after placing the counterweight 30, by limiting the vehicle speed, the safety performance of the entire machine can be improved to prevent exceeding the load capacity of the tire.

[0086] A third aspect of the present application provides a truck crane, comprising a chassis 10 and a counterweight detection and speed limit system as described above, arranged on the chassis 10; a turntable 50 is mounted on the chassis 10, a boom 40 is rotatably mounted on the turntable 50, a control module 20 is mounted at the front end of the chassis 10, and a weight detection component is mounted on the turntable 50.

[0087] In a truck crane, since the boom 40 is very long, when the whole machine is traveling, the boom 40 installed on the turntable 50 has the risk of being unbalanced, thus causing safety hazards. The installation of the counterweight 30 can effectively balance the weight of the boom 40. After adding the counterweight 30, the weight of the counterweight 30 is obtained through the weight detection component, and the maximum speed allowed by the whole machine under the current counterweight 30 is calculated through the weight of the counterweight 30 and the weight of the whole machine, so as to control the whole machine to travel within the maximum speed range.

[0088] In the description of the present application, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0089] In this application, 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 connection; 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 this application can be understood according to specific circumstances.

[0090] 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 present application. 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.

[0091] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for detecting a speed limit of a counterweight of a truck crane, the truck crane comprising a chassis (10) and a counterweight (30) and an engine arranged on the chassis (10), characterized in that: The counterweight detection speed limiting method is applied to a counterweight detection speed limiting system, and the counterweight detection speed limiting method comprises the steps of: Obtaining weight information of the counterweight (30) and weight information of the entire machine; Calculating the axle loads of the front and rear axles according to the weight information of the counterweight (30) and the weight information of the entire machine; Import the axle loads of the front and rear axles into the preset curve diagram and calculate the maximum vehicle speed allowed by the whole machine; Controlling the engine to travel at a speed not exceeding the maximum allowed speed; The axle load of the front and rear axles can be calculated by the following formula: + G 3 + G 4 in, G 1 is the axle load carried by the front axle; G is the weight of the counterweight (30); G 2 is the axle load carried by the rear axle; G 3 is the axle load borne by the front axle excluding the counterweight (30); G 4 is the axle load borne by the rear axle excluding the counterweight (30); L 1 is the distance between the placement position of the counterweight (30) and the front axle; L 2 is the distance between the placement position of the counterweight (30) and the rear axle.

2. The method for detecting speed limit of counterweight of a truck crane according to claim 1, characterized in that: The counterweight detection speed limiting system comprises: A weight detection component, used for detecting the weight of the counterweight (30) and sending a weight information signal; A control module (20) comprises a control unit and an electrical controller, wherein the control unit is electrically connected to the weight detection component, the control unit is used to calculate the maximum allowed vehicle speed according to the weight information signal, and the electrical controller is electrically connected to the control unit, and the electrical controller is used to send a speed limit instruction to the engine according to the maximum allowed vehicle speed.

3. The method for detecting speed limit of counterweight of a truck crane according to claim 2, characterized in that: The chassis (10) is provided with a lifting cylinder (90) for lifting the counterweight (30), and the weight detection component comprises: A hydraulic component mounted on the outer peripheral wall of the lifting cylinder (90) and connected to the oil circuit of the lifting cylinder (90); A pressure detection component is provided at the bottom of the hydraulic component, and is used to detect the hydraulic oil pressure of the hydraulic component and send a hydraulic oil pressure signal. The pressure detection component is electrically connected to the control unit, and the control unit is further configured as follows: receiving a hydraulic oil pressure signal sent by the pressure detection component; The weight of the counterweight (30) is calculated according to the hydraulic oil pressure signal and a weight information signal is sent.

4. The method for detecting speed limit of counterweight of a truck crane according to claim 3, characterized in that: A locking member (31) is provided between the lifting cylinder (90) and the bottom of the counterweight (30).

5. The method for detecting speed limit of counterweight of a truck crane according to claim 2, characterized in that: The weight detection assembly comprises a weight sensor disposed between the counterweight (30) and the frame, the weight sensor being used to detect the weight of the counterweight (30) and send a weight information signal, the control unit being electrically connected to the weight sensor and further configured as follows: A weight signal of the counterweight (30) sent by the weight sensor is received and the weight signal of the counterweight (30) is sent.

6. The method for detecting speed limit of counterweight of a truck crane according to claim 1, characterized in that: The step of importing the axle loads of the front and rear axles into a preset curve diagram and calculating the maximum vehicle speed allowed by the whole machine includes: Importing the axle load of the front axle into the preset curve graph to obtain a first vehicle speed corresponding to the axle load of the front axle; Importing the axle load of the rear axle into the preset curve graph to obtain a second vehicle speed corresponding to the axle load of the front axle; The first vehicle speed and the second vehicle speed are compared, and the minimum value between the two is used as the maximum vehicle speed allowed by the whole machine in the current state.

7. The method for detecting and limiting the speed of a truck crane counterweight according to claim 1, characterized in that: The step of controlling the engine to travel at a speed not exceeding the maximum allowed speed comprises: Calculating the maximum speed required by the engine according to the maximum allowed vehicle speed; The engine is controlled to rotate at a speed not exceeding the maximum speed.

8. The method for detecting speed limit of counterweight of a truck crane according to claim 1, characterized in that: The step of obtaining the preset curve graph comprises: Obtain the maximum load of the wheel corresponding to multiple different speeds; With speed as the horizontal coordinate and the maximum load of the wheel as the vertical coordinate, multiple scattered points are obtained in the coordinate system; Draw curves of multiple scattered points in the same coordinate system to obtain a preset curve graph.

9. A truck crane, characterized in that: The invention comprises a chassis (10) and a counterweight detection speed limit system arranged on the chassis (10), wherein the counterweight detection speed limit system adopts the counterweight detection speed limit method according to any one of claims 1 to 8 to perform speed limit detection, a turntable (50) is installed on the chassis (10), and a boom (40) is rotatably installed on the turntable (50), and the counterweight detection speed limit system comprises a control module (20) and a weight detection component, wherein the control module (20) is installed at the front end of the chassis (10), and the weight detection component is installed on the turntable (50).

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