Flexible rotation limiting mechanism, control method and engineering machinery

Abstract

The invention discloses a flexible rotation limiting mechanism, a control method and engineering machinery. The flexible rotation limiting mechanism comprises two flexible buffering speed reduction assemblies symmetrically arranged on a lower frame and a stop block assembly fixed to an upper frame located between the two flexible buffering speed reduction assemblies. The flexible buffering speed reduction assembly comprises an outer shell, a flexible buffering component, a pressure detection component and a first elastic rubber block. When the upper frame rotates, the check block assembly penetrates into an arc-shaped guide groove in the outer shell and then makes contact with a first elastic rubber block to achieve limiting buffering, kinetic energy is converted into elastic potential energy, then the elastic potential energy is converted into a pressure electric signal, the pressure electric signal is fed back to a hydraulic oil control system, and the hydraulic oil control system controls the upper frame to rotate. The flow of the hydraulic oil is gradually reduced along with the gradual increase of the pressure, an alarm is given to remind a driver to set a rated pressure value, and when the elastic potential energy reaches a set value, hydraulic oil supply is directly cut off, and the upper frame stops running.

Description

Technical Field

[0001] The invention relates to a flexible rotary limiting mechanism, belonging to the technical field of engineering machinery. Background Art

[0002] Hydraulic excavators generally include an upper vehicle, an lower vehicle, and a slewing mechanism, with the upper vehicle connected to the outer slewing circle and the lower vehicle connected to the inner slewing circle. In wide working environments such as engineering construction and mining, the upper vehicle of the excavator can use the slewing mechanism to perform circling operations around the slewing center of the lower vehicle. However, in some narrow or specific working conditions, in order to avoid collisions between the working device and hydraulic pipelines and surrounding walls or rocks, the excavator is only allowed to operate within a specified angle range to ensure operational safety. At present, the slewing limit mechanism has limited angle limits, does not have a variety of angle limit functions, cannot accurately control the slewing angle, has poor flexibility, and is inconvenient to operate.

[0003] The utility model patent with publication number CN209277227U proposes a rotation limit mechanism, in which a stopper is installed on the upper frame and a stopper is fixed on the lower frame, and the rotation angle is limited by adjusting the circumferential distance of the upper frame buffer; the utility model patent with publication number CN214940593U proposes a rotation limit structure for engineering machinery, in which stoppers representing different angles are staggered and welded on the lower frame along the radial direction of the rotation center, and the rotation angle is controlled by adjusting the mating part fixed on the upper frame and in contact with it; the utility model patent with publication number CN214194730 has a similar limiting principle to the above, and the angle limit is achieved by mechanical collision. The limit mechanism of the above patent has some disadvantages: during the mechanical limit process, the collision between the stoppers will cause a huge impact, and in the working state, the kinetic energy of the upper frame is very large, and the vibration caused by the impact can easily damage the equipment, posing a huge safety risk. The patent CN209277227U mentioned above adds a buffer device. In actual work, the buffer device is simply relied on to absorb the huge rotational energy of the excavator when working, which is prone to fatigue failure, resulting in the loss of the limit function. At the same time, the frequent replacement of shock absorbers of different lengths increases the maintenance cost.

[0004] The invention patent with publication number CN113235690A proposes a slewing limit mechanism, which is achieved by pre-welding a specific slideway on the lower frame, installing two sliders on the slideway, and fixing the sliders according to the working angle; at the same time, a proximity switch is installed on the upper frame, and the hydraulic oil circuit is controlled by the cooperation between the proximity switch and the slider to realize the slewing limit function. Publication numbers CN219343366U and CN114809180A also adopt similar limit principles. The above patent principle also has some disadvantages, for example; in the actual working process, a large amount of dirt and dust will accumulate on the lower frame or be submerged in mud and water, causing the proximity switch of the upper frame to fail to work normally, causing the excavator to fail to work within the specified angle, posing a major safety hazard. Summary of the invention

[0005] In view of the deficiencies in the prior art, the utility model provides a flexible rotation limit mechanism, which is assembled, easy to install, disassemble and maintain, and has an adjustable rotation angle stroke, and can cope with narrow working conditions at different angles.

[0006] The present invention is implemented according to the following technical solutions: In a first aspect, the present invention provides a flexible rotation limiting mechanism, comprising two flexible buffer deceleration assemblies symmetrically arranged on a lower frame and a stopper assembly fixed on an upper frame between the two flexible buffer deceleration assemblies; The flexible buffer deceleration assembly comprises: The outer shell is an arc-shaped box-shaped structure, which is mounted on the outer circumferential surface of the lower frame and extends along the circumference of the lower frame. An arc-shaped guide groove extending from the circumferential end portion I to the circumferential end portion II is provided on the top plate of the outer shell; A flexible buffer component is installed in the arc-shaped cavity of the outer shell, and when no external force acts on the flexible buffer component, the circumferential ends of the flexible buffer component extend to the circumferential end portion I and the circumferential end portion II of the outer shell respectively; A pressure detection component is mounted on one end of the flexible buffer component close to the circumferential end portion II; A first elastic rubber block is mounted on the other end of the flexible buffer component close to the circumferential end portion I; Among them, the block assembly can follow the upper frame to perform rotational motion on the lower frame. When the upper frame rotates, the block assembly penetrates into the arc guide groove and contacts the first elastic rubber block to achieve limit buffering, converting kinetic energy into elastic potential energy, and then into a pressure electrical signal.

[0007] In some embodiments, the outer shell is detachably fixed to the outer circumferential surface of the lower frame, and the rotation angle travel of the upper frame is adjusted by changing the position where the outer shell is installed on the lower frame.

[0008] In some embodiments, the outer shell is provided with a dovetail groove extending from the circumferential end II to the circumferential end I on the arc-shaped inner side plate facing the lower frame; a guide rail extending along its circumference is fixed to the outer circumferential surface of the lower frame by bolts, and the cross-section of the guide rail is a dovetail structure. The outer shell is fixed to the lower frame by tightly clamping the guide rail in the dovetail groove, and the relative circumferential rotation of the outer shell and the guide rail is limited by limiting components arranged at both circumferential ends of the dovetail groove.

[0009] In some embodiments, the length of the dovetail groove is consistent with the length of the guide rail, and a baffle plate II serving as the limiting component is fixed at the groove opening of the dovetail groove on the side plate of the outer shell body located at the circumferential end II, and the movement of the guide rail is limited by blocking the groove opening by baffle plate II; a baffle plate I serving as the limiting component is fixed on the arc-shaped inner plate at the circumferential end of the other dovetail groove opposite to the groove, and the movement of the guide rail is limited by baffle plate I.

[0010] In some embodiments, the flexible buffer component comprises: A stopper, fixed on the inner side surface of the outer shell side plate at the circumferential end II; an arc-shaped guide rod, one end of which is fixed to the central area of ​​the stopper and the other end of which extends to the circumferential end portion I of the outer shell; The limit spring is sleeved on the arc-shaped guide rod, and a connecting block is fixed to the limit spring near the circumferential end I. The first elastic rubber block is fixed on the connecting block, and the central areas of the first elastic rubber block and the connecting block are both provided with through holes that allow the arc-shaped guide rod to penetrate.

[0011] In some embodiments, the pressure detection component is a pressure sensor, which is installed on the side of the block facing the limit spring. The limit spring is in contact with the pressure sensor, and the pressure sensor converts different elastic potential energies into different electrical signals; the wiring harness of the pressure sensor passes through the block and the side panel of the outer shell and is electrically connected to the hydraulic oil control system of the vehicle, so as to feed back the electrical signal to the hydraulic oil control system.

[0012] In some embodiments, a first sealing plate for covering the arc guide groove is provided on the top plate of the outer shell, and the first sealing plate is connected to the first elastic rubber block, and the first sealing plate is driven by the first elastic rubber block to close and open the arc guide groove.

[0013] In some embodiments, the first sealing plate is a flexible arc-shaped pad with magnetic attraction, one end of the arc-shaped pad is fixed on the top plate of the outer shell near the circumferential end portion II, and the other end of the arc-shaped pad is connected to the first elastic rubber block; when the first elastic rubber block contacts the circumferential end portion I, the arc-shaped pad is completely adsorbed on the top plate of the outer shell around the arc-shaped guide groove to seal the arc-shaped guide groove; when the block assembly pushes the first elastic rubber block to move, the first elastic rubber block drives the arc-shaped pad to gradually detach from the top plate of the outer shell, thereby opening the arc-shaped guide groove so that the block assembly can penetrate into the arc-shaped guide groove.

[0014] In some embodiments, the stopper assembly comprises: The mounting block is a T-shaped structure as a whole, comprising a horizontal plate and a vertical plate, wherein the horizontal plate is fixed to the upper frame by bolts, and the vertical plate is provided with a through hole I opening toward the outer shell; The second elastic rubber block is symmetrically mounted on both side surfaces of the vertical plate, and is provided with a through hole II. The through holes II on both sides and the middle through hole I form an arc through hole, which is convenient for the arc guide rod in the flexible buffer component to penetrate.

[0015] In some embodiments, the outer shell is provided with a window on the curved outer plate away from the lower frame for assembling the flexible buffer component, the pressure detection component and the first elastic rubber block, and a second sealing plate for sealing the window is fixed on the curved outer plate by bolts.

[0016] In a second aspect, the present invention provides an engineering machine, comprising: Lower the frame; An upper frame capable of performing a rotary motion on the lower frame; A flexible rotation limiting mechanism as mentioned above.

[0017] In a third aspect, the present invention provides a control method based on the above-mentioned flexible rotary limit mechanism: When the upper frame performs a rotational motion on the lower frame, the block assembly only performs a reciprocating circumferential motion between the two flexible buffer deceleration assemblies, and this rotation angle range is a normal working range; When the upper frame swivels at an angle beyond the normal working range, the second elastic rubber block in the block assembly starts to mechanically contact the first elastic rubber block, and the limit spring in the flexible buffer component is compressed. At this time, the elastic potential energy of the limit spring is transmitted to the pressure detection component, and the pressure detection component converts different elastic potential energies into different electrical signals. The control system controls the hydraulic oil flow of the swivel mechanism according to different electrical signals. The greater the elastic potential energy, the smaller the hydraulic oil flow of the swivel mechanism. When the rotation angle of the upper frame reaches the preset limit position, the control system cuts off the hydraulic oil supply to the rotation mechanism, the upper frame stops rotating, and the alarm system sounds an alarm to remind the driver that he has reached the danger zone.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention can absorb the rotation kinetic energy of the excavator and convert it into elastic potential energy through mechanical contact, and then convert it into different pressure electrical signals. The electrical signals can be used to control the hydraulic oil flow of the rotation mechanism, control the rotation speed of the excavator, and accurately control the rotation angle of the excavator, thereby avoiding the impact of traditional rigid mechanical collisions on the equipment and ensuring the safety of the equipment and operators.

[0019] 2. The present invention can realize the rotation limit function for different rotation angles of the equipment by reasonably setting the length of the limit spring, thereby ensuring its wide applicability.

[0020] 3. This flexible rotation limit mechanism is designed to accurately control the hydraulic oil flow rate and the rotation speed and other parameters based on energy conversion, which can meet the rotation limit requirements of the equipment under high torque and high load conditions.

[0021] 4. Most parts of the flexible limit mechanism of the present invention are realized by mechanical parts and structures, without using complicated electrical components or solenoid valves and other components, and the structure is simple, safe and reliable; the whole adopts an assembled structure, which is easy to install, disassemble and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0023] In the attached picture: Figure 1 It is a schematic diagram of the application of a flexible rotary limiting mechanism of the present invention; Figure symbols: 1. upper frame; 2. flexible buffer deceleration assembly; 3. block assembly; 4. lower frame.

[0024] Figure 2 It is a schematic diagram of the overall structure of the flexible buffer deceleration assembly of the present invention; Figure 3 It is an exploded schematic diagram of the flexible buffer deceleration assembly of the present invention; Figure identification: 201, first bolt; 202, first closing plate; 203, guide rail; 204, second bolt; 205, outer shell; 206, stop block; 207, limit spring; 208, second closing plate; 209, limit component; 210, first elastic rubber block; 211, arc-shaped guide rod; 212, outer shell top plate; 213, outer shell side plate; 214, circumferential end portion I; 215, circumferential end portion II; 216, arc-shaped guide groove; 217, arc-shaped inner plate; 218, arc-shaped outer plate; 219, connecting block.

[0025] Figure 4 It is a schematic diagram of the overall structure of the stopper assembly of the present invention; Figure symbols: 301, mounting block; 302, gasket; 303, third bolt; 304, fourth bolt; 305, second elastic rubber block.

[0026] Figure 5 It is a schematic diagram of the narrow working area of ​​the excavator of the present invention.

[0027] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0029] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] like Figure 1 , Figure 2 , Figure 3, Figure 4 As shown, a flexible rotation limit mechanism includes two flexible buffer deceleration assemblies 2 symmetrically arranged on the lower frame 4 and a block assembly 3 fixed on the upper frame 1 between the two flexible buffer deceleration assemblies 2; the flexible buffer deceleration assembly 2 includes an outer shell 205, a flexible buffer component, a pressure detection component, and a first elastic rubber block 210; the outer shell 205 is an arc box-shaped structure, which is installed on the outer circumferential surface of the lower frame 4 and extends along the circumference of the lower frame 4, and an arc guide groove 216 extending from the circumferential end Ⅰ214 to the circumferential end Ⅱ215 is provided on the top plate 212 of the outer shell; the flexible buffer component is installed in the arc cavity of the outer shell 205, and when no external force acts on the flexible buffer component, the circumferential ends of the flexible buffer component extend to the outer shell 205 respectively. Circumferential end Ⅰ214 and circumferential end Ⅱ215; the pressure detection component is installed on one end of the flexible buffer component near the circumferential end Ⅱ215; the first elastic rubber block 210 is installed on the other end of the flexible buffer component near the circumferential end Ⅰ214; wherein, the block assembly 3 can follow the upper frame 1 to perform a rotational motion on the lower frame 4. When the upper frame 1 rotates, the block assembly 3 penetrates into the arc guide groove 216 and contacts with the first elastic rubber block 210 to achieve limit buffering, converting kinetic energy into elastic potential energy, and then into a pressure electrical signal, which is fed back to the hydraulic oil control system. As the pressure gradually increases, the flow of hydraulic oil is gradually reduced, and an alarm is issued to remind the driver to set the rated pressure value. When the elastic potential energy reaches the set value, the hydraulic oil supply is directly cut off, and the upper frame stops running. The flexible rotation limit mechanism can slowly reduce the operating speed of the excavator, smoothly transition until it stops, and avoid the harm caused by huge impact.

[0032] In a further solution, the outer shell 205 is detachably fixed to the outer circumferential surface of the lower frame 4, which is convenient for installation, disassembly and maintenance. The rotation angle travel of the upper frame 1 can be adjusted by changing the position where the outer shell 205 is installed on the lower frame 4, so as to cope with narrow working conditions at different angles.

[0033] like Figure 2 , Figure 3 As shown, the outer shell 205 is provided with a dovetail groove extending from the circumferential end II 215 to the circumferential end I 214 on the arc-shaped inner side plate 217 facing the lower frame 4; a guide rail 203 extending along the circumference thereof is fixed on the outer circumferential surface of the lower frame 4 by a second bolt 204, and the cross section of the guide rail 203 is a dovetail structure, and the outer shell 205 is fixed to the lower frame 4 by the guide rail 203 being tightly clamped in the dovetail groove, and the relative circumferential rotation of the outer shell 205 and the guide rail 203 is limited by the limiting components 209 provided at both ends of the circumferential direction of the dovetail groove.

[0034] Further solutions, such as Figure 2 , Figure 3As shown, the length of the dovetail groove is consistent with the length of the guide rail, the length of the outer shell 205 is about 100 mm greater than the length of the guide rail 203, and the outer shell side plate 213 located at the circumferential end II 215 has a baffle II used as a limiting component 209 fixed at the notch of the dovetail groove by a first bolt 201, and the notch is blocked by baffle II to limit the movement of the guide rail 203; a baffle I used as a limiting component 209 is fixed on the arc-shaped inner plate 217 at the circumferential end of the other dovetail groove opposite to the notch, and the movement of the guide rail 203 is limited by baffle I.

[0035] The specific structure of the above-mentioned flexible buffer component is further described below.

[0036] like Figure 2 , Figure 3 As shown, the flexible buffer component includes a stopper 206, an arc-shaped guide rod 211, and a limit spring 207; the stopper 206 is fixed to the inner side surface of the outer shell side plate 213 at the circumferential end II 215 by a first bolt 201; one end of the arc-shaped guide rod 211 is fixed to the central area of ​​the stopper 206, and the other end extends to the circumferential end I 214 of the outer shell 205; the limit spring 207 is sleeved on the arc-shaped guide rod 211, and the limit spring 207 is fixed with a connecting block 219 near the circumferential end I 214, the first elastic rubber block 210 is fixed to the connecting block 219 by a first bolt 201, and the central areas of the first elastic rubber block 210 and the connecting block 219 are provided with through holes that allow the arc-shaped guide rod 211 to penetrate.

[0037] The specific structure of the above-mentioned pressure detection component is further described below.

[0038] like Figure 2 , Figure 3 As shown, the pressure detection component is a pressure sensor, which is installed on the side of the block 206 facing the limit spring 207. The limit spring 207 is in contact with the pressure sensor. The pressure sensor converts different elastic potential energies into different electrical signals; the wiring harness of the pressure sensor passes through the block 206 and the side plate 213 of the outer shell and is electrically connected to the hydraulic oil control system of the whole vehicle, so as to feed back the electrical signal to the hydraulic oil control system.

[0039] Further solutions, such as Figure 2 , Figure 3 As shown, a first sealing plate 202 for covering the arc guide groove 216 is provided on the top plate 212 of the outer shell body. The first sealing plate 202 is connected to the first elastic rubber block 210. The first sealing plate 202 is driven by the first elastic rubber block 210 to close and open the arc guide groove 216. The non-working state is in a related state to prevent dust and dirt from entering.

[0040] In a preferred embodiment, the first sealing plate 202 is a flexible arc-shaped pad with magnetic attraction, one end of the arc-shaped pad is fixed to the outer shell top plate 212 near the circumferential end portion II 215 by a first bolt 201, and the other end of the arc-shaped pad is connected to the first elastic rubber block 210 by the first bolt 201; when the first elastic rubber block 210 contacts the circumferential end portion I 214, the arc-shaped pad is completely adsorbed on the outer shell top plate 212 around the arc-shaped guide groove 216, so as to seal the arc-shaped guide groove 216; when the block assembly 3 pushes the first elastic rubber block 210 to move, the first elastic rubber block 210 drives the arc-shaped pad to gradually detach from the outer shell top plate 212, thereby opening the arc-shaped guide groove 216, so that the block assembly 3 can penetrate into the arc-shaped guide groove 216.

[0041] Further solutions, such as Figure 2 , Figure 3 As shown, the outer shell 205 is provided with a window on the arc-shaped outer plate 218 away from the lower frame 4 for assembling the flexible buffer component, the pressure sensor and the first elastic rubber block 210, and a second sealing plate 208 for sealing the window is fixed on the arc-shaped outer plate 218 by the first bolt 201.

[0042] As can be seen from the above, the flexible buffer deceleration assembly 2 is installed in an assembled manner as a whole, which is easy to install, disassemble and maintain, and has the advantages of flexible limit and adjustable limit angle. At the same time, it can convert the rotational energy of the upper frame 1 into elastic potential energy, and can convert different elastic potential energies into different pressure electrical signals. The electrical signals are fed back to the control system to gradually reduce the flow of the rotary hydraulic oil circuit until the supply of rotary hydraulic oil is stopped (the flow of rotary hydraulic oil is negatively correlated with the elastic potential energy), so that the excavator stops slowly, thereby achieving safe operation of the excavator in a narrow area.

[0043] The specific structure of the above-mentioned stopper assembly is further described below.

[0044] like Figure 4 As shown, the block assembly includes a mounting block 301 and a second elastic rubber block 305; the mounting block 301 is a T-shaped structure as a whole, including a horizontal plate and a vertical plate, the horizontal plate is fixed to the upper frame 1 by a third bolt 303 and a gasket 302, and the vertical plate is provided with a through hole I opening toward the outer shell 205; the second elastic rubber block 305 is symmetrically mounted on the two side surfaces of the vertical plate by a fourth bolt 304, and the second elastic rubber block 305 is provided with a through hole II, and the through holes II on both sides and the middle through hole I constitute an arc-shaped through hole, which is convenient for the arc-shaped guide rod 211 in the flexible buffer component to penetrate.

[0045] As can be seen from the above, the block assembly 3 is installed on the upper frame 1, and its motion state is consistent with the upper frame 1; the flexible deceleration and buffer assembly 2 is installed on the lower frame 3, and its motion state is consistent with the lower frame 3. Under narrow working conditions, when the upper frame 1 rotates to a certain angle, the second elastic rubber block 305 in the block assembly 3 and the first elastic rubber block 210 in the flexible buffer deceleration assembly 2 are in mechanical contact. This contact pair is in contact through elastic material, which can avoid the huge impact and noise generated by direct contact between rigid bodies. As the rotation angle of the upper frame 1 increases, the limit spring 207 will be further compressed. The pressure sensor 206 converts different electrical signals into different input control systems according to the compression amount of the limit spring 207. At this time, the control system reduces the flow rate of the rotary hydraulic oil accordingly and issues an alarm sound at the same time. The greater the compression amount of the limit spring 207, the smaller the flow rate of the hydraulic oil of the rotary system. When the limit position is reached, the supply of the rotary hydraulic oil is cut off and the machine stops working. The flexible rotary limit mechanism can slowly reduce the operating speed of the excavator, smoothly transition until it stops, and avoid the harm caused by huge impact.

[0046] The engineering machinery provided by the present invention is described below. The engineering machinery described below and the flexible rotary limiting mechanism described above can be referred to each other.

[0047] An engineering machine provided by the present invention may include the flexible rotation limiting mechanism as described in any one of the above embodiments.

[0048] The beneficial effects achieved by the engineering machinery provided by the present invention are consistent with the beneficial effects achieved by the flexible rotary limiting mechanism provided by the present invention, and will not be described in detail here.

[0049] It should be noted that the above-mentioned engineering machinery may be a crawler excavator or a wheeled excavator.

[0050] Taking an excavator as an example, the control method of the above-mentioned flexible rotation limit mechanism is described in detail below.

[0051] Figure 5As shown in the schematic diagram of the narrow working area of ​​the excavator, this area is collectively referred to as the safe working area, which can be divided into three parts: the working area, the buffer area and the limit position. According to the pre-planned working area angle, the flexible buffer deceleration assembly 2 is installed on both sides of the lower frame 3. When the excavator reciprocates in the normal working area, the flexible buffer deceleration assembly 2 will not be triggered. When the excavator's rotation angle exceeds the normal working area angle, the second elastic rubber block 305 begins to mechanically contact with the first elastic rubber block 210, and the limit spring 207 is compressed along the guide rod 211. At this time, the elastic potential energy of the limit spring 207 is transmitted to the pressure sensor, and the pressure sensor converts different elastic potential energies into different electrical signals. The control system controls the hydraulic oil flow of the slewing mechanism according to different electrical signals. The greater the elastic potential energy (the greater the excavator's rotation angle), the smaller the hydraulic oil flow of the slewing mechanism, which can slowly reduce the excavator's rotation movement. When the rotation angle reaches the specified limit value, the hydraulic oil supply of the slewing mechanism is cut off, and the excavator stops rotating. At the same time, the buzzer sounds an alarm to remind the driver to reach the dangerous area. At this time, when the driver operates the excavator to reverse, the elastic potential energy of the limit spring 207 gradually decreases, and the flow of the rotary hydraulic oil gradually increases until it reaches the normal working area. When the reverse angle reaches the buffer area, the flexible buffer deceleration assembly 2 starts to work, and the principle is consistent with the above, so that the operating range of the excavator in a narrow area can be accurately controlled. When the limit spring 207 reciprocates along the guide rod 211, the first sealing plate 202 will reciprocate accordingly, ensuring that the first sealing plate 202 is open when working and in a closed state when not working, which can prevent dust and dirt from entering.

[0052] In summary, the present invention provides a flexible rotation limit mechanism and a control method thereof, which achieve the following functions and effects: 1. The present invention can absorb the rotation kinetic energy of the excavator and convert it into elastic potential energy through mechanical contact, and then convert it into different pressure electrical signals. The electrical signals can be used to control the hydraulic oil flow of the rotation mechanism, control the rotation speed of the excavator, and accurately control the rotation angle of the excavator, thereby avoiding the impact of traditional rigid mechanical collisions on the equipment and ensuring the safety of the equipment and operators.

[0053] 2. The present invention can realize the rotation limit function for different rotation angles of the equipment by reasonably setting the length of the limit spring, thereby ensuring its wide applicability.

[0054] 3. This flexible rotation limit mechanism is designed to accurately control the hydraulic oil flow rate and the rotation speed and other parameters based on energy conversion, which can meet the rotation limit requirements of the equipment under high torque and high load conditions.

[0055] 4. Most parts of the flexible limit mechanism of the present invention are realized by mechanical parts and structures, without using complicated electrical components or solenoid valves and other components, and the structure is simple, safe and reliable; the whole adopts an assembled structure, which is easy to install, disassemble and maintain.

[0056] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0057] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0058] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the present invention can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A flexible rotation limiting mechanism, characterized in that: It includes two flexible buffer deceleration assemblies symmetrically arranged on the lower frame and a stopper assembly fixed on the upper frame between the two flexible buffer deceleration assemblies; The flexible buffer deceleration assembly comprises: The outer shell is an arc-shaped box-shaped structure, which is mounted on the outer circumferential surface of the lower frame and extends along the circumference of the lower frame. An arc-shaped guide groove extending from the circumferential end portion I to the circumferential end portion II is provided on the top plate of the outer shell; A flexible buffer component is installed in the arc-shaped cavity of the outer shell, and when no external force acts on the flexible buffer component, the circumferential ends of the flexible buffer component extend to the circumferential end portion I and the circumferential end portion II of the outer shell respectively; A pressure detection component is mounted on one end of the flexible buffer component close to the circumferential end portion II; A first elastic rubber block is mounted on the other end of the flexible buffer component close to the circumferential end portion I; Among them, the block assembly can follow the upper frame to perform rotational motion on the lower frame. When the upper frame rotates, the block assembly penetrates into the arc guide groove and contacts the first elastic rubber block to achieve limit buffering, converting kinetic energy into elastic potential energy, and then into a pressure electrical signal.

2. A flexible rotation limiting mechanism according to claim 1, characterized in that: The outer shell is detachably fixed to the outer circumferential surface of the lower frame, and the rotation angle stroke of the upper frame can be adjusted by changing the position of the outer shell installed on the lower frame.

3. A flexible rotation limiting mechanism according to claim 2, characterized in that: The outer shell is provided with a dovetail groove extending from the circumferential end II to the circumferential end I on the arc-shaped inner side plate facing the lower frame; A guide rail extending along the circumference is fixed to the outer circumferential surface of the lower frame by bolts, and the cross-section of the guide rail is a dovetail structure. The outer shell is fixed to the lower frame by tightly clamping the guide rail in the dovetail groove, and the relative circumferential rotation between the outer shell and the guide rail is limited by limiting components arranged at both ends of the dovetail groove.

4. A flexible rotation limiting mechanism according to claim 3, characterized in that: The length of the dovetail groove is consistent with the length of the guide rail, and a baffle plate II serving as the limiting component is fixed at the notch of the dovetail groove on the side plate of the outer shell at the circumferential end II, and the movement of the guide rail is limited by blocking the notch of the baffle plate II; A baffle plate I serving as the limiting component is fixed on the arc-shaped inner side plate at the circumferential end of the other dovetail groove opposite to the notch, and the movement of the guide rail is limited by the baffle plate I.

5. The flexible rotation limiting mechanism according to claim 1, characterized in that: The flexible buffer component comprises: A stopper, fixed on the inner side surface of the outer shell side plate at the circumferential end II; an arc-shaped guide rod, one end of which is fixed to the central area of ​​the stopper and the other end of which extends to the circumferential end portion I of the outer shell; The limit spring is sleeved on the arc-shaped guide rod, and a connecting block is fixed to the limit spring near the circumferential end I. The first elastic rubber block is fixed on the connecting block, and the central areas of the first elastic rubber block and the connecting block are both provided with through holes that allow the arc-shaped guide rod to penetrate.

6. A flexible rotation limiting mechanism according to claim 5, characterized in that: The pressure detection component is a pressure sensor, which is installed on the side of the stopper facing the limit spring. The limit spring is in contact with the pressure sensor, and the pressure sensor converts different elastic potential energies into different electrical signals. The wiring harness of the pressure sensor passes through the block and the side plate of the outer shell and is electrically connected to the hydraulic oil control system of the whole vehicle, so as to feed back the electrical signal to the hydraulic oil control system.

7. The flexible rotation limiting mechanism according to claim 1, characterized in that: A first sealing plate for covering the arc-shaped guide groove is disposed on the top plate of the outer shell, and the first sealing plate is connected to the first elastic rubber block, and the first sealing plate is driven by the first elastic rubber block to close and open the arc-shaped guide groove.

8. The flexible rotation limiting mechanism according to claim 7, characterized in that: The first sealing plate is a flexible arc-shaped pad with magnetic attraction, one end of which is fixed to the top plate of the outer shell near the circumferential end II, and the other end of which is connected to the first elastic rubber block; When the first elastic rubber block contacts the circumferential end portion I, the arc pads are all adsorbed on the top plate of the outer shell around the arc guide groove to seal the arc guide groove; When the stopper assembly pushes the first elastic rubber block to move, the first elastic rubber block drives the arc pad to gradually separate from the top plate of the outer shell, thereby opening the arc guide groove so that the stopper assembly can penetrate into the arc guide groove.

9. The flexible rotation limiting mechanism according to claim 1, characterized in that: The stopper assembly comprises: The mounting block is a T-shaped structure as a whole, comprising a horizontal plate and a vertical plate, wherein the horizontal plate is fixed to the upper frame by bolts, and the vertical plate is provided with a through hole I opening toward the outer shell; The second elastic rubber block is symmetrically mounted on both side surfaces of the vertical plate, and is provided with a through hole II. The through holes II on both sides and the middle through hole I form an arc through hole, which is convenient for the arc guide rod in the flexible buffer component to penetrate.

10. The flexible rotation limiting mechanism according to claim 1, characterized in that: The outer shell is provided with a window on the arc-shaped outer plate away from the lower frame for assembling the flexible buffer component, the pressure detection component and the first elastic rubber block, and a second sealing plate for sealing the window is fixed on the arc-shaped outer plate by bolts.

11. An engineering machine, characterized in that: include: Lower the frame; An upper frame capable of performing a rotary motion on the lower frame; A flexible rotation limiting mechanism as claimed in any one of claims 1 to 10.

12. A control method of a flexible rotary limit mechanism according to any one of claims 1 to 10, characterized in that: When the upper frame performs a rotational motion on the lower frame, the block assembly only performs a reciprocating circumferential motion between the two flexible buffer deceleration assemblies, and this rotation angle range is a normal working range; When the upper frame swivels at an angle beyond the normal working range, the second elastic rubber block in the block assembly starts to mechanically contact the first elastic rubber block, and the limit spring in the flexible buffer component is compressed. At this time, the elastic potential energy of the limit spring is transmitted to the pressure detection component, and the pressure detection component converts different elastic potential energies into different electrical signals. The control system controls the hydraulic oil flow of the swivel mechanism according to different electrical signals. The greater the elastic potential energy, the smaller the hydraulic oil flow of the swivel mechanism. When the rotation angle of the upper frame reaches the preset limit position, the control system cuts off the hydraulic oil supply to the rotation mechanism, the upper frame stops rotating, and the alarm system sounds an alarm to remind the driver that he has reached the danger zone.

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