Heavy load telescopic mechanism and adjustment method of telescopic mechanism guide gap

Abstract

The application discloses a heavy-load telescopic mechanism and a telescopic mechanism guiding gap adjusting method, which comprises a slide assembly and a slide rail assembly connected to the slide assembly; the slide assembly comprises a slide, the slide is provided with a dovetail-shaped sliding groove, the bottom surface of the dovetail-shaped sliding groove is provided with a slide sticking plate, and the two side surfaces of the dovetail-shaped sliding groove are provided with sliding plates; the slide rail assembly comprises a slide rail, the two side surfaces of the slide rail are wedge-shaped, the bottom surface and the two side surfaces of the slide rail are provided with sticking plates, the sticking plates are in surface contact with the slide sticking plate and the sliding plates, and the slide rail is slidingly connected in the dovetail-shaped sliding groove; the slide is provided with a clamping device, the clamping device comprises an outer cylinder, a single-acting oil cylinder is arranged in the outer cylinder, the single-acting oil cylinder comprises a cylinder barrel, a piston rod and a joint, the cylinder barrel is sleeved in the outer cylinder, the piston rod is in contact with the back surface of the sliding plate, the joint is arranged at the top end of the cylinder barrel and communicates with the inside of the cylinder barrel, and the top end of the cylinder barrel is provided with a locking block for limiting. The application has the functions of clamping and buffering and can reduce abrasion.

Description

Technical Field

[0001] This invention relates to the field of tunneling machine technology, and in particular to a heavy-duty telescopic mechanism and a method for adjusting the guide clearance of the telescopic mechanism. Background Technology

[0002] Traditional cantilever tunneling machines often add a telescopic cantilever section to the cutting section. This telescopic method often uses a circumferentially arranged flat key to resist the torque and vibration generated during the cutting process. Due to the space limitation of the telescopic cantilever section, the size of the flat key is limited. Therefore, when the tunneling machine cuts semi-coal and rock or rock tunnels, the flat key often wears out prematurely due to the large cutting torque and large cutting vibration, which in turn leads to the premature failure of the telescopic mechanism.

[0003] The cutting process of a cantilever tunneling machine has two modes: feed-and-cut mode and swing (up-and-down, left-and-right) cutting mode. In the feed-and-cut mode, the telescopic mechanism needs to operate, while in the swing cutting mode, the telescopic mechanism can operate or not. Comparing the two cutting modes, the swing cutting mode experiences significantly greater cutting reaction forces and vibrations than the feed-and-cut mode. When the cutting mechanism is cutting coal and rock while the telescopic mechanism is advancing, the reaction forces and vibrations generated during the cutting process will impact the telescopic mechanism. The relatively sliding components inside the traditional telescopic mechanism are rigidly connected, and under large cutting reaction forces and vibrations, they will experience mutual impact and wear, leading to premature failure of the telescopic mechanism. In addition, the traditional telescopic mechanism can operate in both cutting modes, making it extremely prone to wear under large cutting reaction forces and vibrations, which will also ultimately lead to premature failure of the telescopic mechanism.

[0004] Chinese invention patent CN114109431A discloses a flexible connection structure for an external telescopic mechanism of an all-rock tunneling machine. The frame body includes a frame and a slide block. The slide block is provided with a dovetail-shaped slide groove. A first sliding bearing is provided on the bottom surface of the dovetail-shaped slide groove, and a second sliding bearing is provided on both sides. The telescopic sliding device includes a cutting section base and a telescopic drive device. The cutting section base is slidably connected in the dovetail-shaped slide groove through the first and second sliding bearings. The telescopic drive device can drive the cutting section base to slide. The cutting section base includes a sliding bottom surface that slides in contact with the first sliding bearing and a sliding side surface that slides in contact with the second sliding bearing. A floating compensation clamping device can generate a force on the second sliding bearing toward the cutting section base so that the sliding bottom surface and the sliding side surface are tightly fitted with the first and second sliding bearings, respectively. The telescopic mechanism of this invention adopts a dovetail groove type integral telescopic mechanism with a large bearing area and a small contact specific pressure when subjected to cutting reaction force, which has an impact resistance function. It can be applied to rock cutting in semi-coal-rock tunnels and rock tunnels. Its floating compensation clamping device has a clamping function, can compensate for gaps after the sliding bearing wears, and has an overload protection function. However, it is still a rigid connection. The clamping needs to take into account two cutting methods at the same time, which has a certain negative impact on the telescopic mechanism and requires further improvement.

[0005] Traditional telescopic mechanisms typically ensure guide clearance through machining or by using relatively simple shims. This method of ensuring or adjusting clearance is effective for some small or light telescopic mechanisms, but for heavy telescopic mechanisms, this method of adjusting guide clearance is not only difficult to guarantee in terms of accuracy, but also time-consuming and labor-intensive during assembly. In addition, if the clearance is too large, the internal impact of the telescopic mechanism will increase, leading to premature failure of the telescopic mechanism. If the clearance is too small, it will lead to increased friction and accelerate the wear of the telescopic mechanism. Summary of the Invention

[0006] The purpose of this invention is to provide a heavy-duty telescopic mechanism and a method for adjusting the guide clearance of the telescopic mechanism, so as to solve the problems existing in the prior art.

[0007] The technical solution adopted by the present invention is to provide a heavy-duty telescopic mechanism. The telescopic mechanism includes a slide rail assembly mounted on a frame assembly, a slide rail assembly connected to the slide rail assembly, and a rotary support mounted on the slide rail assembly for connecting the cutting part.

[0008] The slide assembly includes a slide, on which a dovetail-shaped groove is provided, a slide plate is provided on the bottom surface of the dovetail-shaped groove, and sliding plates are provided on both sides of the dovetail-shaped groove.

[0009] The slide rail assembly includes a slide rail with wedge-shaped sides. The bottom and sides of the slide rail are provided with a plate, which contacts the slide rail plate and the sliding plate surface, so that the slide rail is slidably connected in the dovetail groove.

[0010] Multiple clamping devices are arranged on one side of the slide. Each clamping device includes an outer cylinder fixedly connected to the side of the slide. A single-acting hydraulic cylinder is installed in the outer cylinder. The single-acting hydraulic cylinder includes a cylinder barrel, a piston rod, and a connector. The cylinder barrel is sleeved in the outer cylinder. The piston rod contacts the back of the sliding plate to push the sliding plate to move. The connector is located at the top of the cylinder barrel and connects to the inside of the cylinder barrel for injecting hydraulic oil. A locking block is installed at the top of the cylinder barrel for limiting the movement. The outer wall of the locking block is provided with external threads, which are threaded to the internal threads provided on the inner wall of the outer cylinder.

[0011] Furthermore, a guide gap is provided between the top of the cylinder and the locking block.

[0012] Furthermore, the guide clearance is the same as the maximum stroke of the single-acting hydraulic cylinder's telescopic movement.

[0013] Furthermore, during the feeding and grooving process, the hydraulic oil pressure in the cylinder is P1, which enables the telescopic mechanism to operate and compresses the cylinder during impact vibration.

[0014] Furthermore, during the swing cutting, the hydraulic oil pressure in the cylinder is P2, which prevents the telescopic mechanism from operating.

[0015] Furthermore, the external thread of the locking block is a self-locking thread, and the locking block is self-locked by the self-locking device.

[0016] Furthermore, an end cap is provided at the top of the outer cylinder.

[0017] Furthermore, baffles are provided at the front and rear of the slide to restrict the sliding plate.

[0018] Furthermore, a mud scraping device is fixedly connected to the front and rear of the sliding plate and the sliding track plate, and the mud scraping side of the mud scraping device presses tightly against the plate.

[0019] The heavy-duty telescopic mechanism of the present invention has a clamping function. When the cantilever tunneling machine swings and cuts, the cutting reaction force is large and the cutting vibration is strong. In order to avoid wear and impact on the telescopic mechanism, the present invention introduces high-pressure oil into the single-acting oil cylinder inside the clamping device. Under the action of the single-acting oil cylinder, the telescopic mechanism is clamped and cannot move, thus avoiding premature failure of the telescopic mechanism.

[0020] The heavy-duty telescopic mechanism of the present invention also has a buffer function. When the telescopic mechanism performs telescopic grooving, the single-acting cylinder will maintain a certain small pressure and a certain telescopic stroke (also the guide clearance). When the telescopic mechanism is subjected to a large impact, the slide rail assembly will slowly squeeze the left and right slide rails under the action of the single-acting cylinder, thus avoiding excessive wear of the friction pair of the telescopic mechanism.

[0021] The present invention also provides a method for adjusting the guide clearance of a telescopic mechanism, comprising:

[0022] Step 1: The single-acting hydraulic cylinder is filled with oil, and the piston rod acts on the sliding plate to push the slide rail assembly to its limit position;

[0023] Step 2: Depressurize the single-acting hydraulic cylinder and rotate the locking block to move it towards the cylinder barrel, thereby pushing the cylinder barrel to its limit position;

[0024] Step 3: Rotate the locking block in the opposite direction by an angle α to make the guide clearance between the locking block and the cylinder L. The angle α is calculated from the thread pitch and the set clearance L.

[0025] Step 4: Tighten the internal screws to lock the locking block and secure the connecting end cover.

[0026] The guide clearance adjustment method provided by this invention has high adjustment accuracy and is simple and highly mechanized, ensuring the reliable and stable operation of the telescopic mechanism. At the same time, the guide clearance set by this invention can prevent the telescopic mechanism from crawling or not moving during the feeding and grooving operation. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention;

[0028] Figure 2 This is a cross-sectional schematic diagram of the present invention;

[0029] Figure 3 yes Figure 2 A magnified view of a portion of the image;

[0030] In the diagram: 1-Telescopic mechanism, 11-Left slide rail assembly, 111-Left slide rail, 112-Upper left sliding plate, 113-Lower left slide rail plate, 12-Right slide rail assembly, 121-Right slide rail, 122-Upper right sliding plate, 123-Lower right slide rail plate, 13-Slide rail assembly, 131-Slide rail, 132-Upper left plate, 133-Lower left plate, 134-Upper right plate, 135-Lower right plate, 14-Clamping device 141-Single-acting hydraulic cylinder, 1411-Piston rod, 1412-Cylinder barrel, 1413-Piston seal, 1414-Connector, 1415-Oil port, 142-Outer cylinder, 143-Locking block, 1431-External thread, 1432-Internal screw, 144-End cap, 15-Baffle, 16-Upper scraper, 17-Lower scraper, 2-Frame assembly, 3-Slewing support, 4-Telescopic push cylinder. Detailed Implementation

[0031] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides an explanation of a heavy-duty telescopic mechanism and a method for adjusting the guide clearance of the telescopic mechanism.

[0032] like Figures 1-3As shown, a heavy-duty telescopic mechanism is disclosed. The telescopic mechanism 1 includes a slide rail assembly mounted on a frame assembly 2. A matching slide rail assembly 13 is connected to the slide rail assembly. A slewing support 3 is provided on the slide rail assembly 13 for connecting the cutting part. The slide rail assembly includes a slide rail with a dovetail-shaped groove. A slide rail plate is provided on the bottom surface of the dovetail-shaped groove, and sliding plates are provided on both sides of the dovetail-shaped groove. The slide rail assembly 13 includes a slide rail 131 with wedge-shaped sides. Plates are provided on the bottom surface and both sides of the slide rail 131. The plates contact the slide rail plate and the sliding plates, allowing the slide rail 131 to slide in the dovetail-shaped groove. Multiple sets of sliding rails are arranged on one side of the slide rail. The clamping device 14 includes an outer cylinder 142 fixedly connected to the side of the slide rail. A single-acting hydraulic cylinder 141 is disposed in the outer cylinder 142. The single-acting hydraulic cylinder 141 includes a cylinder barrel 1412, a piston rod 1411, and a connector 1414. The cylinder barrel 1412 is sleeved in the outer cylinder 142. The piston rod 1411 contacts the back of the sliding plate to push the sliding plate to move. The connector 1414 is disposed at the top of the cylinder barrel 1412 and communicates with the inside of the cylinder barrel 1412 for injecting hydraulic oil. A locking block 143 is disposed at the top of the cylinder barrel 1412. The outer wall of the locking block 143 is provided with external threads 1431, which are threadedly connected to the internal threads provided on the inner wall of the outer cylinder 142. By introducing hydraulic oil into the single-acting hydraulic cylinder inside the clamping device 14, different pressures can be set for different cutting methods to clamp the telescopic mechanism 1, avoiding wear and impact on the telescopic mechanism 1 during cutting.

[0033] In this embodiment, the mounting plate includes an upper left mounting plate 132, a lower left mounting plate 133, an upper right mounting plate 134, and a lower right mounting plate 135. The upper left mounting plate 132 is fixedly connected to the upper left side of the slide rail 131, the lower left mounting plate 132 is fixedly connected to the lower left side of the slide rail 131, the upper right mounting plate 134 is fixedly connected to the upper right side of the slide rail 131, and the lower right mounting plate 135 is fixedly connected to the lower right side of the slide rail 131.

[0034] The slide assembly consists of a left slide assembly 11 and a right slide assembly 12. The lower end of the slide assembly is fixedly connected to the frame assembly 2. Specifically, the left slide 111 of the left slide assembly 11 and the right slide 121 of the right slide assembly 12 are fixedly connected to the frame assembly 2.

[0035] The left slide rail assembly 11 also includes an upper left sliding plate 112 and a lower left slide rail plate 113. The upper left sliding plate 112 is installed in the groove of the left slide rail 111 and can slide in the groove. The lower left slide rail plate 113 is fixedly installed below the left slide rail 111. Baffles 15 are installed in front of and behind the left slide rail 111 to prevent the upper left sliding plate 112 from sliding out of the left slide rail 111 in the front-back direction. The upper left sliding plate 112 is fixedly connected to the upper scraping device 16 in front of and behind, and the scraping side presses against the upper left plate 132. The lower left slide rail plate 113 is fixedly connected to the lower scraping device 17 in front of and behind, and the scraping side presses against the lower left plate 133.

[0036] The right slide rail assembly 12 also includes an upper right sliding plate 122 and a lower right slide rail plate 123. The upper right sliding plate 122 is installed in the groove of the right slide rail 121 and can slide in the groove. The lower right slide rail plate 123 is fixedly installed below the right slide rail 121. Baffles 15 are installed in front of and behind the right slide rail 121 to prevent the upper right sliding plate 122 from sliding out of the right slide rail 121 in the front-back direction. The upper mud scraper 16 is fixedly connected to the front and rear of the upper right sliding plate 122, and the mud scraper side presses against the upper right plate 134. The lower mud scraper 17 is fixedly connected to the front and rear of the lower right slide rail plate 123, and the mud scraper side presses against the lower right plate 135.

[0037] The upper scraper 16 and the lower scraper 17 are mainly used to remove coal sludge from the plates on the slide rail assembly 13, prevent coal sludge from entering the friction pair, and avoid damage to the friction pair.

[0038] The upper left sliding plate 112 and the upper left mounting plate 132 form the first pair of friction pairs; the lower left sliding plate 113 and the lower left mounting plate 133 form the second pair of friction pairs; the upper right sliding plate 122 and the upper right mounting plate 134 form the third pair of friction pairs; and the lower right sliding plate 123 and the lower right mounting plate 135 form the fourth pair of friction pairs. The two surfaces of the friction pairs need to have good lubricity and high hardness. Additionally, oil grooves are arranged inside the upper left sliding plate 112, the lower left sliding plate 113, the upper right sliding plate 122, and the lower right sliding plate 123, allowing grease to enter between the two surfaces of the friction pairs and provide lubrication.

[0039] In an optional instance, the left slide assembly 11 and the right slide assembly 12 may be an integral part.

[0040] In this embodiment, the lower end of the slewing support 3 is fixedly connected to the slide rail assembly 13. Specifically, the lower end of the slewing support 3 is connected to the slide rail 131 of the slide rail assembly 13, and the upper end of the slewing support 3 is connected to the slewing lug of the tunneling machine, and then to the cutting part.

[0041] In this embodiment, one end of the telescopic push cylinder 4 is hinged to the rear end connecting lug of the slide rail assembly 13, and the other end of the telescopic push cylinder 4 is hinged to the relevant connecting lug of the frame assembly 2. By extending and shortening the telescopic push cylinder 4, the slide rail assembly 13 can move in the front-back direction relative to the left slide rail assembly 11 and the right slide rail assembly 12, so that the cutting mechanism of the tunneling machine can move in the front-back direction relative to the frame assembly 2, thereby increasing the cutting range of the tunneling machine without moving the machine and improving the cutting efficiency.

[0042] Multiple sets of clamping devices 14 are arranged, and the clamping devices 14 are arranged on one side of the left slide rail assembly 11 or the right slide rail assembly 12. In this embodiment, six sets of clamping devices 14 are arranged, and they are arranged on one side of the right slide rail assembly 12. The right slide rail 121 of the right slide rail assembly 12 has a number of circular holes equal to the number of clamping devices 14 for installing the clamping devices 14. The clamping device 14 includes an outer cylinder 142 fixedly connected to the top of the circular holes. A single-acting hydraulic cylinder 141 is arranged inside the outer cylinder 142, which can slide up and down inside the outer cylinder 142. The single-acting hydraulic cylinder 141 includes a piston rod 1411, a cylinder barrel 1412, and a connector 1414. The cylinder barrel 1412 is sleeved in the outer cylinder 142. The piston rod 1411 contacts the back of the sliding plate to push the sliding plate to move. The connector 1414 is located at the top of the cylinder barrel 1412 and communicates with the inside of the cylinder barrel 1412 for injecting hydraulic oil.

[0043] A locking block 143 is provided at the top of the cylinder 1412 for limiting the position. The upper part of the inner cylinder 142 has an internal thread, and the outer side of the locking block 143 has an external thread. The locking block 143 is connected to the outer cylinder 142 by threads, so that the locking block 143 can move relative to the outer cylinder 142 in the vertical direction through thread engagement.

[0044] The locking block 143 in this embodiment has a self-locking function. That is, by tightening the internal screw 1432 axially arranged on the locking block 143, the self-locking external thread 1431 of the locking block 143 has a certain amount of contraction in the vertical direction, so that the external thread 1431 of the locking block 143 is pressed against the internal thread of the outer cylinder 142, and the locking block 143 is fixed relative to the outer cylinder 142. The locking block 143 is not limited to the one shown in this example.

[0045] The piston rod 1411 of the single-acting hydraulic cylinder 141 is located inside the cylinder barrel 1412. The outer circle of the piston rod 1411 and the inner circle of the cylinder barrel 1412 are cylindrically fitted, allowing the piston rod 1411 to slide up and down relative to the cylinder barrel 1412. A piston seal 1413 is arranged between the piston rod 1411 and the cylinder barrel 1412 to prevent hydraulic oil leakage. The connector 1414 is fixedly connected to the top of the cylinder barrel 1412 by a threaded connection. Hydraulic oil can enter the cylinder barrel 1412 through the oil port 1415 of the connector 1414, pushing the piston rod 1411 to move downward. The locking block 143 is pressed and locked above the single-acting hydraulic cylinder 141, specifically the cylinder barrel 1412 of the single-acting hydraulic cylinder 141 is pressed and locked with the locking block 143. The bottom of the single-acting hydraulic cylinder 141 is in close contact with the upper right sliding plate 122, specifically the bottom of the piston rod 1411 of the single-acting hydraulic cylinder 141 is in close contact with the upper right sliding plate 122.

[0046] In this embodiment, an end cap 144 is fixedly connected above the outer cylinder 142 to prevent dust and other impurities from entering the clamping device 14.

[0047] The telescopic mechanism of this invention is a heavy-duty dovetail groove type telescopic mechanism, which is suitable for cantilever tunneling machines to operate in rock tunnels. The cantilever tunneling machine has a large self-weight of its cutting mechanism and the reaction force generated by the trenching operation. The working conditions of the heavy-duty telescopic mechanism of this invention are described below and corresponding solutions are provided.

[0048] There are two cutting methods for cantilever tunneling machines: feed-and-cut method and swing-and-cut method. Feed-and-cut method requires a telescopic mechanism to extend and retract, and the cutting head is in a rotating drilling and cutting position. The cutting force and vibration are relatively small. However, when the cutting mechanism is not in a horizontal position, the telescopic mechanism will be subjected to a certain lateral force. Swing-and-cut method involves the cutting head rotating and milling, resulting in a relatively large cutting force, and the swing-and-cut method generates significant lateral force and vibration.

[0049] During the feeding and grooving process, when the pressure of the single-acting cylinder 141 of the clamping device 14 is high, the friction between the slide rail assembly 13 and the left slide rail assembly 11 and the right slide rail assembly 12 will increase. On the one hand, the increased friction will exceed the maximum thrust of the telescopic push cylinder 4, ultimately causing the telescopic mechanism to fail to operate. On the other hand, it will also aggravate the wear between each pair of friction pairs. Therefore, in order to ensure cutting stability, the single-acting cylinder 141 of the clamping device 14 needs to maintain a certain low pressure P1 to drive the piston rod 1411 to extend downward relative to the cylinder 1412, thereby causing the piston rods 1411 of all single-acting cylinders 141 to push each pair of friction pairs of the telescopic mechanism to fit tightly.

[0050] All single-acting cylinders 141 maintain a certain pressure P1 inside, and the reaction force generated during the cutting process results in a certain pressure FNi between each pair of friction pairs. When the telescopic push cylinder 4 pushes the slide rail assembly 13 to move relative to the left slide rail assembly 11 and the right slide rail assembly 12, the pressure FN formed between all friction pairs will generate friction force Ff between the slide rail assembly 13 and the left slide rail assembly 11 and the right slide rail assembly 12 during the telescopic process of the telescopic mechanism 1. At this time, the friction force Ff is less than the maximum thrust Fp of the telescopic push cylinder 4. Therefore, under the premise that the friction coefficient μ is constant, the pressure FN formed between all friction pairs has a maximum limit value FNmax. Consequently, the holding pressure P1 of each single-acting cylinder 141 in the feeding and grooving method cannot exceed a certain limit value. Otherwise, the telescopic push cylinder 4 will be unable to push the telescopic mechanism to move due to excessive friction between the friction pairs. Therefore, the value of P1 is a small value.

[0051] When the cutting mechanism performs grooving, especially when the cutting reaction force, cutting lateral force, and cutting vibration are large, the slide rail assembly 13 of the telescopic mechanism 1 will have a certain impact on the left slide rail assembly 11 or the right slide rail assembly 12. Ultimately, this impact force will act on the left slide rail 111 or the right slide rail 121 through each pair of friction pairs and each clamping device 14. At the same time, the telescopic mechanism will affect each pair of friction pairs and the left slide rail 111 and the right slide rail 121 during the forward and backward movement. On the one hand, when the impact force and vibration are too large, they will cause wear on these components; on the other hand, the impact force will also increase the friction between each pair of friction pairs. In severe cases, the telescopic mechanism will crawl or fail to move. Therefore, the telescopic mechanism needs a certain guide clearance L to enable the telescopic mechanism to move more smoothly. This guide clearance L plays a key role in the reliable and stable operation of the telescopic mechanism.

[0052] The guide clearance L cannot be too large; otherwise, when the cutting reaction force or cutting vibration is large, the telescopic mechanism 1 will shake. Specifically, the slide rail assembly 13 will shake relative to the left slide rail assembly 11 and the right slide rail assembly 12, which may cause wear or failure of the telescopic mechanism in severe cases. Similarly, the guide clearance L cannot be too small; otherwise, when the cutting reaction force changes abruptly, the telescopic mechanism 1 may crawl or fail to operate. Therefore, the precise adjustment of the guide clearance L is crucial. At the same time, due to the existence of the guide clearance L, each clamping device 14 of the present invention forms a buffer mechanism inside. The buffer mechanism needs both a certain buffer resistance and a certain buffer stroke. The buffer resistance is provided by the single-acting hydraulic cylinder 141, and the buffer stroke is provided by the guide clearance L.

[0053] The specific implementation method of each function of the telescopic mechanism 1 in the entire feeding and grooving process is as follows: In the feeding and grooving mode, when the telescopic mechanism is in the feeding and grooving mode, the hydraulic oil with a lower pressure of P1 enters the cylinder 1412 through the oil port 1415 of all single-acting cylinders 141. The cylinder 1412 is limited by the locking block 143 above it. The hydraulic oil pushes the piston rod 1411 to extend downward, and then pushes the upper right sliding plate 122 to move in the right slide rail 121. This further pushes the entire slide rail assembly 13 to move to the left and downward, so that the slide rail assembly 13 is in close contact with the left slide rail assembly 11 and the right slide rail assembly 12 respectively. That is, the upper left sliding plate 112 is pressed against the upper left plate 132, the lower left slide rail plate 113 is pressed against the lower left plate 133, the upper right sliding plate 122 is pressed against the upper right plate 134, and the lower right slide rail plate 123 is pressed against the lower right plate 135. By extending and retracting the hydraulic cylinder 4, the slide rail assembly 13 can move forward relative to the left slide rail assembly 11 and the right slide rail assembly 12. Each single-acting hydraulic cylinder 141 maintains pressure P1, and each single-acting hydraulic cylinder 141 extends to its maximum stroke (i.e., the distance the piston rod 1411 extends relative to the cylinder barrel 1412). This maximum stroke is also the guide clearance L of the entire telescopic mechanism 1.

[0054] When the telescopic mechanism performs grooving operations and is subjected to significant cutting reaction force and vibration, the cutting reaction force and vibration will ultimately act on the telescopic mechanism 1 through the cutting mechanism, specifically through the slide rail assembly 13 to the left slide rail 111 or the right slide rail 121. When the torque generated by the cutting reaction force in the vertical direction acts on the left slide rail 111 or the right slide rail 121 through the slide rail assembly 13, the slide rail assembly 13 will push one end of the upper left sliding plate 112 and the other end of the upper right sliding plate 122 (towards the left). The upper sliding plate 112 (opposite end) presses towards the left side of the left slide rail 111 and the right side of the right slide rail 121. When the pressing force is too large, the single-acting cylinder 141 maintains a certain pressure P1 inside, which causes the slide rail assembly 13 to push the upper right sliding plate 122 and then push the piston rod 1411 of the single-acting cylinder 141 to slowly move to the upper right to the maximum stroke. Finally, the slide rail assembly 13 slowly acts on the left slide rail assembly 11 and the right slide rail assembly 12, reducing the impact.

[0055] When the cutting mechanism is in the swing cutting mode, the telescopic mechanism experiences much greater reaction force and vibration from the cutting mechanism than in the feed grooving mode. Even if the telescopic mechanism 1 has a buffer mechanism, the large cutting reaction force and vibration will still impact the telescopic mechanism 1, especially the left slide 111 of the left slide assembly 11 and the right slide 121 of the right slide assembly 12. It will also cause wear to the upper left sliding plate 112 and the lower left slide plate 113 of the left slide 111, as well as the upper right sliding plate 122 and the lower right slide plate 123 of the right slide assembly 12. In severe cases, the telescopic mechanism will fail. Therefore, this invention requires that the telescopic mechanism 1 should not operate when the cutting mechanism is in the swing cutting mode.

[0056] The specific implementation method is as follows: In the swing cutting mode, when the telescopic mechanism 1 is in the swing cutting mode, the hydraulic oil with a higher pressure of P2 enters the cylinder 1412 through the oil port 1415 of all single-acting cylinders 141. The cylinder 1412 is limited by the locking block 143 above it. The hydraulic oil pushes the piston rod 1411 to extend downward, and then pushes the upper right sliding plate 122 to move in the right slide rail 121. This further pushes the entire slide rail assembly 13 to move to the left and downward, so that the slide rail assembly 13 is in close contact with the left slide rail assembly 11 and the right slide rail assembly 12 respectively. That is, the upper left sliding plate 112 is pressed with the upper left plate 132, the lower left slide rail plate 113 is pressed with the lower left plate 133, the upper right sliding plate 122 is pressed with the upper right plate 134, and the lower right slide rail plate 123 is pressed with the lower right plate 135. Each single-acting cylinder 141 maintains a certain higher pressure P2. At this time, the telescopic mechanism 1 cannot move.

[0057] Due to the special structure of the dovetail groove telescopic mechanism of this invention, it is impossible to guarantee the guide clearance of the entire telescopic mechanism through processing. In this embodiment, the method for quickly adjusting the guide clearance of the telescopic mechanism is as follows:

[0058] First, each single-acting cylinder 141 is activated, that is, hydraulic oil enters the cylinder barrel 1412 of each single-acting cylinder 141 through the oil port 1415 of the connector 1414, the piston rod 1411 extends, and then pushes the upper right sliding plate 122 to move in the right slide rail 121, further pushing the entire slide rail assembly 13 to move to the left and downward, so that the slide rail assembly 13 is in close contact with the left slide rail assembly 11 and the right slide rail assembly 12 respectively, that is, the upper left sliding plate 112 is in close contact with the upper left plate 132, the lower left slide rail plate 113 is in close contact with the lower left plate 133, the upper right sliding plate 122 is in close contact with the upper right plate 134, and the lower right slide rail plate 123 is in close contact with the lower right plate 135.

[0059] Then, each single-acting cylinder 141 is depressurized, that is, the internal pressure of each cylinder 1412 and piston rod 1411 is depressurized. At this time, the rotating locking block 143 moves downward (that is, moves towards the cylinder 1412), thereby pushing the cylinder 1412 downward until the cylinder 1412 stops moving.

[0060] Then, the locking block 143 is rotated in the opposite direction by a certain angle. The angle of the reverse rotation of the locking block 143 is calculated based on the thread pitch and the reserved guide clearance L. After the reverse rotation is completed, the locking block 143 is locked, that is, the locking block 143 is fixed relative to the outer cylinder 142. At this time, a certain guide clearance L is left between the locking block 143 and the cylinder 1412, which is both the guide clearance L of the telescopic mechanism 1 and the maximum stroke of the single-acting cylinder 141 that can be telescopic.

[0061] Finally, each end cap 144 is fixedly connected to the top of each outer cylinder 142, and the gap adjustment is completed.

[0062] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A heavy-duty telescopic mechanism, the telescopic mechanism (1) includes a slide rail assembly disposed on a frame assembly (2), a slide rail assembly (13) connected thereto and a rotary support (3) disposed on the slide rail assembly (13) for connecting the cutting part; The slide assembly includes a slide, on which a dovetail-shaped groove is provided, a slide plate is provided on the bottom surface of the dovetail-shaped groove, and sliding plates are provided on both sides of the dovetail-shaped groove; The slide rail assembly (13) includes a slide rail (131), the two sides of the slide rail (131) are wedge-shaped, and the bottom surface and two sides of the slide rail (131) are provided with a plate. The plate contacts the slide rail plate and the sliding plate surface, so that the slide rail (131) is slidably connected in the dovetail groove. Multiple clamping devices (14) are arranged on one side of the slide, characterized in that... The clamping device (14) includes an outer cylinder (142) fixedly connected to the side of the slide. A single-acting hydraulic cylinder (141) is provided in the outer cylinder (142). The single-acting hydraulic cylinder (141) includes a cylinder barrel (1412), a piston rod (1411), and a connector (1414). The cylinder barrel (1412) is sleeved in the outer cylinder (142). The piston rod (1411) contacts the back of the sliding plate to push the sliding plate to move. The connector (1414) is provided at the top of the cylinder barrel (1412) to communicate with the inside of the cylinder barrel (1412) for injecting hydraulic oil. A locking block (143) is provided at the top of the cylinder barrel (1412) for limiting. The outer wall of the locking block (143) is provided with an external thread (1431) which is threadedly connected to the internal thread provided on the inner wall of the outer cylinder (142). A guide gap is provided between the top of the cylinder (1412) and the locking block (143); The guide clearance is the same as the maximum stroke of the telescopic movement of the single-acting hydraulic cylinder (141); During the feeding and grooving process, the hydraulic oil pressure in the cylinder (1412) is P1, which enables the telescopic mechanism to operate and compresses the cylinder (1412) during impact and vibration. During the swing cutting, the hydraulic oil pressure in the cylinder (1412) is P2, which prevents the telescopic mechanism from operating.

2. The heavy-duty telescopic mechanism according to claim 1, characterized in that, The external thread (1431) of the locking block (143) is a self-locking thread, and the locking block (143) is self-locked by the self-locking device.

3. The heavy-duty telescopic mechanism according to claim 2, characterized in that, The self-locking device includes an internal screw (1432) axially arranged on the locking block (143). The internal screw (1432) can press the external thread (1431) of the locking block (143) against the internal thread of the outer cylinder (142), so that the locking block (143) is fixed relative to the outer cylinder (142). The top of the outer cylinder (142) is provided with an end cap (144).

4. The heavy-duty telescopic mechanism according to claim 1, characterized in that, Baffles (15) are provided at the front and rear of the slide to restrict the sliding plate.

5. The heavy-duty telescopic mechanism according to claim 1, characterized in that, The sliding plate and the sliding track plate are fixedly connected to the front and rear of the mud scraping device, and the mud scraping side of the mud scraping device is pressed tightly against the plate.

6. A method for adjusting the guide clearance of a telescopic mechanism, employing the heavy-duty telescopic mechanism as described in claim 3, characterized in that, include: Step 1: The single-acting cylinder (141) is filled with oil, and the piston rod (1411) acts on the sliding plate to push the slide rail assembly (13) to the limit position; Step 2: Depressurize the single-acting cylinder (141), rotate the locking block (143) to move towards the cylinder barrel (1412) side, thereby pushing the cylinder barrel (1412) to the limit position; Step 3: Rotate the locking block (143) in the opposite direction by an angle α so that the guide clearance between the locking block (143) and the cylinder (1412) is L. The angle α is calculated from the thread pitch and the set guide clearance L. Step 4: Tighten the internal screw (1432) to lock the locking block (143) and fix the connecting end cover (144).

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