A square hole excavation method using an excavation device with a limit protection function

Abstract

The present invention provides an excavation device with a limit protection function and a square hole excavation method thereof, which are applicable to the field of engineering construction. The excavation device of the present invention includes a control cantilever, an eccentric rotating shaft, a spiral drill bit and a limit protection device, wherein the limit protection device includes a limit frame and a card plate, wherein the limit frame has an annular groove for accommodating the outer periphery of the card plate, the upper end of the limit frame is fixedly connected to the control cantilever, and the eccentric rotating shaft is connected directly below the control cantilever. The lower end of the connecting shaft of the eccentric rotating shaft is connected to the driving gear through the driving shaft through the cam assembly, and the driven shaft of the eccentric rotating shaft passes through the center of the card plate and is connected to the spiral drill bit. The present invention solves the problem that the horizontal lateral force of the drill bit of the excavation equipment increases suddenly, causing the cam assembly and the gear connection to be easily damaged. When the spiral drill bit encounters inclined rocks or hard objects, the limit protection device can provide a certain horizontal lateral force constraint. When it is detected that the horizontal side pressure exceeds a certain threshold, an automatic alarm is issued to prompt the on-site personnel to stop the excavation work.

Description

Technical Field

[0001] The invention relates to a square hole excavation method with excavation equipment having a limit protection function, which is suitable for the square hole excavation direction in the engineering construction field. Background Art

[0002] In the traditional machining industry, the Leuleau triangle principle is often used for square hole opening operations. The square hole opening efficiency based on this principle is very high, and it is particularly suitable for square hole opening operations under the condition of uniform hardness of materials, such as application on homogeneous materials such as metal sheets. However, when this principle is applied to complex scenarios such as excavation of square or rectangular holes in the engineering industry, problems such as unclear geological conditions of underground soil layers, inconsistent hardness, and uneven distribution will be encountered. For example, when excavating holes for foundation engineering, hard stones may suddenly be dug up, especially when the surface of the rock block is horizontally inclined, which will cause a sudden increase in the horizontal lateral force acting on the drill bit, and the drill bit similar to a cantilever device will produce a large bending moment on the gear transmission part, thereby damaging the cam assembly on the upper part of the gear, making it impossible for the gear to remain in meshing state.

[0003] Since construction machinery is larger than traditional machinery, the cost of replacing parts on site is high and heavy equipment is difficult to maintain. Therefore, it is necessary to continuously improve and optimize the equipment during the construction process, especially the durability of the equipment's weak and key connection nodes, to ensure stable operation of the equipment and reduce maintenance costs.

[0004] Therefore, it is very necessary to provide an excavation device with a limit protection function, so that the key points and weak nodes of the device can be protected while the device can efficiently excavate square holes. In addition, for the improved square hole excavation device, it is also necessary to provide a corresponding square hole excavation method to guide the staff to perform excavation operations. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that the sudden increase in the horizontal lateral force of the drill bit of the engineering square hole excavation equipment leads to the easy damage of the connection between the root of the drill bit and the gear, reduce the maintenance frequency and improve work efficiency, and provide an excavation equipment with a limit protection function, which has the advantages of reducing the number of idle times, reducing costs and increasing efficiency, and can be widely used in the excavation direction of square holes in the field of engineering construction.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The gear assembly is connected to the control arm, and the driven gear is engaged with the driven gear by the driven shaft, and the driven gear is engaged with the driven gear by the driven shaft.

[0008] As a preferred technical solution of the present invention, the clamping plate is a Lelo triangle structure, and the clamping plate is fixedly connected to the lower end of the driven shaft of the eccentric rotating shaft. When the clamping plate rotates under the action of the driven shaft, its outer contour always remains in the annular groove and will not deviate.

[0009] As a preferred technical solution of the present invention, it also includes a baffle, a through hole for the driven shaft to pass through is opened in the middle of the baffle, and the baffle is fixed to the bottom end of the limiting frame.

[0010] The square hole excavation method of the excavation equipment with the limit protection function of the present invention specifically comprises the following steps:

[0011] S101 obtains excavation equipment parameters;

[0012] The excavation equipment parameters are obtained, including the driven shaft diameter d, the screw drill length l, the shear strength τ and the tensile strength σ of the driven shaft material. t And the compressive strength σ p , compare the tensile strength and the compressive strength, and take the smaller value of the two as σ;

[0013] S102 calculates the pressure threshold of the excavation equipment side;

[0014] The calculating of the pressure threshold of the excavation equipment side includes solving the pressure threshold of the excavation equipment side according to calculation formula (1),

[0015]

[0016] In the formula, η is the safety factor, and its value range is 0.5~0.8;

[0017] S103 feeds back the side pressure during rotary drilling;

[0018] The feedback of the side pressure during the rotary drilling process includes inputting the side pressure threshold into the pressure sensor, the pressure sensor is arranged on the inner wall of the annular groove, and when the measured value of the pressure sensor reaches the side pressure threshold during the rotary drilling process, the pressure sensor sends a warning feedback to the on-site personnel;

[0019] S104 selects the excavation method;

[0020] The selecting of the mining mode includes making the following selections according to whether the pressure sensor has a warning feedback:

[0021] a. If there is no warning feedback, the excavation equipment is used to continue excavating the square hole;

[0022] b. If there is a warning feedback, immediately stop the excavation equipment from digging the square hole, use a special excavation or blasting device to remove the hard obstacles, and use manual excavation for the remaining excavation work.

[0023] As a preferred technical solution of the present invention, in step S3, a pressure threshold warning mechanism is provided in the pressure sensor, and the pressure threshold warning mechanism includes setting a pressure threshold, and when the pressure measurement value reaches the pressure threshold, the pressure sensor will emit a warning sound and feed back to the on-site personnel.

[0024] In summary, the beneficial effects of the present invention are:

[0025] 1. The present invention connects the front end of the square hole excavation equipment with the spiral drill bit through an eccentric rotating shaft, wherein the cam assembly of the eccentric rotating shaft is in the shape of a Reuleaux triangle. Under the action of the eccentric rotating shaft, the central axis of the spiral drill bit reciprocates along the internal small square track by utilizing the Reuleaux triangle principle, and drives the spiral drill bit to move to excavate the square hole. The limit protection device is provided, and the driven shaft is penetrated by a Reuleaux triangle clamping plate, and the clamping plate is limited in the annular groove of the limit frame along the rotation range of the eccentric rotating shaft. Such a setting is to ensure that the reliability of the connection between the cam assembly and the gear will not be damaged due to a sudden increase in horizontal lateral force. The limit protection device itself can provide a large proportion of horizontal lateral force constraints and bending moment constraints, thereby avoiding the spiral drill bit similar to the cantilever device from generating a large bending moment in the gear transmission part, thereby damaging the cam assembly on the upper part of the gear, and making the gear unable to maintain a meshing state.

[0026] 2. The square hole excavation method of the excavation equipment with the limit protection function of the present invention further solves the problem of the sudden increase of horizontal lateral force at the end of the drill bit of the square hole excavation equipment in the project, which causes the drill bit gear connection to be easily damaged, based on the addition of a limit protection device in the excavation equipment. When the square hole excavation equipment in the project encounters a hard object, if the pressure sensor set in the limit protection device exceeds a certain threshold when the horizontal side pressure received by it exceeds a certain threshold, an automatic alarm will be issued to prompt the on-site personnel to stop the excavation work, so as to avoid the drill bit itself being damaged by the horizontal lateral force at the end of the drill bit under the premise that the limit device provides sufficient constraints; a method for using the square hole excavation equipment proposed based on the protection device can guide the on-site personnel to perform square hole excavation work. The present invention has the advantages of reducing maintenance frequency, reducing downtime, and reducing engineering construction costs, and can be widely used in the square hole excavation direction in the field of engineering construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the excavation equipment with position limiting protection function of the present invention;

[0028] Figure 2 It is a schematic diagram of the eccentric shaft structure of the excavation equipment of the present invention;

[0029] Figure 3 yes Figure 1 A cross-sectional view of the limit protection device;

[0030] Figure 4 yes Figure 1 A top view of the limit protection device;

[0031] Figure 5 It is an operation flow chart of the excavation method of the present invention;

[0032] Reference numerals in the figure: 1-control cantilever, 2-limiting frame, 20-annular groove, 3-eccentric rotating shaft, 30-connecting shaft, 31-cam assembly, 32-driving shaft, 33-driving gear, 34-driven gear, 35-driven shaft, 4-spiral drill bit, 5-cage, 6-baffle. DETAILED DESCRIPTION

[0033] 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 given here are only used to illustrate and explain the present invention and cannot be used to limit the present invention. It should be noted that many specific details are set forth in the following description to facilitate a full understanding of the present invention, but the present invention may also have other embodiments and variations thereof, and therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0034] like Figures 1 to 4As shown, the present invention provides an excavation device with a limit protection function, comprising a control boom 1, an eccentric shaft 3, a spiral drill bit 4 and a limit protection device, wherein the limit protection device comprises a limit frame 2 and a clamping plate 5, wherein the limit frame 2 is a U-shaped structure, and an annular groove 20 for accommodating the outer periphery of the clamping plate 5 is formed inside, wherein the upper end of the limit frame 2 is fixedly connected to the control boom 1, and the eccentric shaft 3 is connected to the lower front end of the control boom 1, and the eccentric shaft 3 comprises a connecting shaft 30, a cam assembly 3 1. A driving gear 33 and a driven gear 34. The connecting shaft 30 is connected to the control cantilever 1. The lower end of the connecting shaft 30 is connected to the driving gear 33 through the driving shaft 32 through the cam assembly 31. The driven gear 34 is sleeved on the driven shaft 35. The driven shaft 35 of the eccentric shaft 3 passes through the center of the clamping plate 5 and is connected to the spiral drill bit 4. The driving gear 33 is meshed with the driven gear 34. The rotation of the driven shaft 35 drives the clamping plate 5 and the spiral drill bit 4 to rotate synchronously.

[0035] In the preferred implementation of this embodiment, the clamping plate 5 is a Leroy triangle structure, and the clamping plate 5 is fixedly connected to the lower end of the driven shaft 35 of the eccentric shaft 3. When the clamping plate 5 rotates under the action of the driven shaft 35, its outer contour will always be within the annular groove 20 without deviation. This arrangement is to ensure that the reliability of the connection between the cam assembly 31 and the gear will not be damaged due to a sudden increase in horizontal lateral force, and to avoid the following situation: the spiral drill bit 4 similar to the cantilever device will generate a large bending moment in the gear transmission part, thereby damaging the cam assembly 31 on the upper part of the gear, so that the gear cannot maintain a meshing state.

[0036] The preferred implementation of this embodiment further includes a baffle plate, wherein a through hole for the driven shaft 35 to pass through is formed in the middle of the baffle plate 6, and the baffle plate 6 is fixed to the bottom end of the limit frame 2. The baffle plate 6 is provided to prevent soil and gravel from being splashed by the spiral drill bit 4 during rapid drilling.

[0037] By introducing such limit protection technology, the reliability and durability of engineering equipment will be significantly improved, and the frequency of daily maintenance and emergency maintenance can be reduced. It will not only help improve work efficiency and reduce downtime caused by mechanical damage, but also reduce the total cost of engineering projects.

[0038] The square hole excavation method of the excavation equipment with the limit protection function of the present invention is based on the square hole excavation process of the electric pole of a certain section of a 10kV transmission line project of a certain power grid. The square foundation pit size of the electric pole is 1.1m×1.1m×2.8m, and specifically includes the following steps:

[0039] S101 obtains excavation equipment parameters;

[0040] The excavation equipment parameters are as follows: the driven rod diameter d = 73 mm, the total length of the auger 4 l = 5 m, the driven shaft 35 is made of 42CrMo, the shear strength τ of the driven shaft 35 is 1100 mPa, and the tensile strength σ t =1080mPa and compressive strength σ p =930mPa, compare the tensile strength and the compressive strength, and take the smaller value of the two as σ=930mPa;

[0041] S102 calculates the pressure threshold of the excavation equipment side;

[0042] The pressure threshold of the excavation equipment side is obtained by solving the calculation formula (1):

[0043]

[0044] Where, safety factor η = 0.8;

[0045] In this embodiment, Therefore, the excavation equipment side pressure threshold P t =8.40kN;

[0046] S103 feeds back the side pressure during rotary drilling;

[0047] The side pressure threshold is input to the pressure sensor, and the pressure sensor is arranged on the inner wall of the annular groove 20. When the measured value of the pressure sensor reaches the side pressure threshold during rotary drilling, the pressure sensor emits a warning sound to the on-site personnel;

[0048] S104 selects the excavation method;

[0049] During the excavation process, the pressure sensor emits a warning sound, and the on-site personnel immediately stop the excavation equipment from digging the square hole, use special excavation or blasting equipment to remove the hard obstacles, and the remaining excavation work is carried out by manual excavation.

[0050] In some embodiments, in step S3, a pressure threshold warning mechanism is provided in the pressure sensor, and the pressure threshold warning mechanism includes setting a pressure threshold, and when the pressure measurement value reaches the pressure threshold, the pressure sensor will issue a warning sound and feedback to on-site personnel. If the pressure sensor does not issue a warning sound, it means that the excavation equipment can be used to continue excavation work.

[0051] In summary, the excavation equipment and excavation method of the present invention have the characteristics of high practical value and wide application range in the direction of square hole excavation in the field of engineering construction.

[0052] It should be understood that the above-mentioned embodiments are one or more embodiments of the present invention, and there are many other embodiments and variations thereof based on the present invention; the variations and modifications made by ordinary technicians in this industry through the present invention without making pioneering innovations all fall within the scope of protection of the present invention.

Claims

1. A square hole excavation method with an excavation device having a limit protection function, characterized in that: The following steps are involved: S101 obtains excavation equipment parameters; The excavation equipment includes a control cantilever, an eccentric rotating shaft, a spiral drill bit and a limit protection device, the limit protection device includes a limit frame and a card plate, the limit frame is a U-shaped structure, and an annular groove for accommodating the outer periphery of the card plate is opened inside, the upper end of the limit frame is fixedly connected to the control cantilever, and the eccentric rotating shaft is connected just below the front end of the control cantilever, the eccentric rotating shaft includes a connecting shaft, a cam assembly, a driving gear and a driven gear, the connecting shaft is connected to the control cantilever, the lower end of the connecting shaft is connected to the driving gear through the driving shaft through the cam assembly, the driven gear is sleeved on the driven shaft, the driven shaft of the eccentric rotating shaft passes through the center of the card plate and is connected to the spiral drill bit, the driving gear is meshed with the driven gear, and the rotation of the driven shaft drives the card plate and the spiral drill bit to rotate synchronously; The excavation equipment parameters are obtained, including the driven shaft diameter d, the screw drill length l, the shear strength τ and the tensile strength σ of the driven shaft material. t And the compressive strength σ p , compare the tensile strength and the compressive strength, and take the smaller value of the two as σ; S102 calculates the pressure threshold of the excavation equipment side; The calculating of the pressure threshold of the excavation equipment side includes solving the pressure threshold of the excavation equipment side according to calculation formula (1), In the formula, η is the safety factor, and its value range is 0.5~0.8; S103 feeds back the side pressure during rotary drilling; The feedback of the side pressure during the rotary drilling process includes inputting the side pressure threshold into the pressure sensor, the pressure sensor is arranged on the inner wall of the annular groove, and when the measured value of the pressure sensor reaches the side pressure threshold during the rotary drilling process, the pressure sensor sends a warning feedback to the on-site personnel; S104 selects the excavation method; The selecting of the mining mode includes making the following selections according to whether the pressure sensor has a warning feedback: If there is no warning feedback, continue to dig the square hole using the excavation equipment; If there is a warning feedback, the excavation equipment is immediately stopped from digging the square hole, and a special excavation or blasting device is used to remove the hard obstacles, and the remaining excavation work is carried out by manual excavation.

2. A square hole excavation method with an excavation device having a position limiting protection function according to claim 1, characterized in that: The clamping plate is a Leroy triangle structure, and the clamping plate is fixedly connected to the lower end of the driven shaft of the eccentric shaft. When the clamping plate rotates under the action of the driven shaft, its outer contour always remains in the annular groove and does not deviate.

3. A square hole excavation method with an excavation device having a position limiting protection function according to claim 1, characterized in that: It also includes a baffle, a through hole for the driven shaft to pass through is opened in the middle of the baffle, and the baffle is fixed to the bottom end of the limiting frame.

4. A square hole excavation method with an excavation device having a position limiting protection function according to claim 1, characterized in that: In step S103, a pressure threshold warning mechanism is provided in the pressure sensor, and the pressure threshold warning mechanism includes setting a pressure threshold, and when the pressure measurement value reaches the pressure threshold, the pressure sensor will emit a warning sound and feed back to the on-site personnel.

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