Mast jacking mechanism and crane

Abstract

This invention discloses a mast lifting mechanism and a crane, relating to the field of engineering machinery, to optimize the structure of the mast lifting mechanism so that the mast can be placed flat on a turntable. The mast lifting mechanism includes a turntable, a mast, a guide member, and a lifting cylinder. The mast is rotatably connected to the turntable. The guide member is fixed to one end of the mast near the turntable and includes an open groove. One end of the lifting cylinder is rotatably connected to the turntable, and the other end of the lifting cylinder engages with the groove and is configured to switch between two positions: in the groove and out of the groove. The mast lifting mechanism provided by the above technical solution does not have a lifting frame; the lifting cylinder engages with the guide member, and the guide member is fixedly connected to the mast, enabling the mast to rotate when the lifting cylinder extends. When laid flat, the lifting cylinder can be placed flat on the turntable. Furthermore, the number of components is reduced, the hinge points between components are decreased, and the assembly relationship is reliable.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery, specifically to a mast lifting mechanism and a crane. Background Technology

[0002] Tracked cranes are used in construction, wind power, factories and other scenarios. They combine the high performance of a truss boom with the high load-bearing capacity of a tracked chassis, enabling them to travel under load and greatly improving their operational capabilities and efficiency.

[0003] The mast is a key component of a crawler crane. The mast is hinged to the turntable, and its pitch is achieved via luffing wire ropes. Simultaneously, the mast head is connected to the boom via luffing plates, thus driving the boom to pitch as well. Hydraulic cylinder supports are welded inside the turntable, and the bottom of the lifting cylinder is hinged to these supports. To limit the extension and retraction direction of the lifting cylinder, the cylinder head is hinged to the lifting frame, and the other end of the lifting frame is hinged to the turntable.

[0004] During the relocation process, the mast is placed horizontally on the turntable, with the angle between the mast and the upper surface of the turntable being 0°. When assembling the main unit at the work site, the mast must be rotated until the angle with the turntable is greater than 90° before the auxiliary installation cylinders can be used to hoist and install the various components of the main unit. After the main unit is installed, the auxiliary installation cylinders are retracted, and the mast head is connected to the luffing plate. The other end of the luffing plate is connected to the boom head. When the luffing wire rope is retracted and released, the mast pitches, which in turn drives the boom to pitch.

[0005] The inventors discovered that the existing technology has at least the following problems: the structure of existing crawler cranes is unreasonable. Due to unavoidable manufacturing errors, the lifting frame and the mast do not fit tightly, resulting in gaps and high contact stress. When the mast is subjected to high stress, the lifting frame will deform, causing the mast to be unable to be placed horizontally on the turntable after being lowered; in addition, when the hydraulic cylinder extends to its maximum stroke, interference occurs between the lifting frame and the hydraulic cylinder piston rod. Summary of the Invention

[0006] This invention proposes a mast lifting mechanism and a crane to optimize the structure of the mast lifting mechanism so that the mast can be placed flat on the turntable.

[0007] This invention provides a mast lifting mechanism, comprising:

[0008] Turntable;

[0009] The mast is rotatably connected to the turntable;

[0010] A guide member, fixed to one end of the mast near the turntable, the guide member including an open groove; and

[0011] The lifting cylinder has one end rotatably connected to the turntable and the other end engaged with the slide groove and is configured to switch between two positions: in the slide groove and out of the slide groove.

[0012] In some embodiments, the guide includes:

[0013] The first plate is fixed to one end of the mast near the turntable; and

[0014] The second plate is arranged parallel to the first plate and is also fixed to the end of the mast near the turntable;

[0015] Both the first plate and the second plate include the groove.

[0016] In some embodiments, the chute includes:

[0017] The guide segment is constructed to be straight;

[0018] A transition section, located at the bottom of the guide section, and the transition section is configured to be curved; and

[0019] A limiting segment is located at the end of the transition segment away from the guide segment, and the limiting segment is parallel to the guide segment.

[0020] In some embodiments, when the lifting cylinder rotates to fit against the turntable, the other end of the lifting cylinder is located within the limiting section of the slide groove.

[0021] In some embodiments, the mast lifting mechanism further includes:

[0022] A pin is fixedly connected at its middle part to the piston rod of the lifting cylinder, and both ends of the pin are provided with annular recesses. One of the annular recesses engages with a groove in the first plate, and the other annular recess engages with a groove in the second plate. The annular recess engages with the groove and is configured to switch between two positions: the annular recess is in the groove, and the annular recess is out of the groove.

[0023] In some embodiments, the mast lifting mechanism further includes:

[0024] A hydraulic cylinder bracket is installed on the turntable. The hydraulic cylinder bracket includes a limiting groove, through which the lifting hydraulic cylinder passes. The limiting groove restricts the rotation angle of the lifting hydraulic cylinder relative to the turntable.

[0025] In some embodiments, the cylinder bracket includes:

[0026] The first connecting arm has one end fixedly connected to the turntable;

[0027] The second connecting arm, one end of which is fixedly connected to the turntable; and

[0028] A connector is used to fix one end of the first connecting arm to the other end of the second connecting arm; the connector includes a recess; when the lifting cylinder rotates to its maximum angle with the turntable, the lifting cylinder rests in the recess.

[0029] In some embodiments, after the lifting cylinder rotates to its maximum angle with the turntable, the lifting cylinder retracts to disengage from the slide.

[0030] In some embodiments, the first connecting arm and / or the second connecting arm are configured to be bent.

[0031] In some embodiments, the mast lifting mechanism further includes:

[0032] An angle measuring element is installed at the hinge point between the mast and the turntable; the angle measuring element monitors the angle between the mast and the turntable in real time.

[0033] The control system is electrically connected to the angle detection element; the control system controls the extension and retraction of the lifting cylinder when the included angle measured by the angle measuring element is a set value.

[0034] In some embodiments, the number of lifting cylinders is two, and one lifting cylinder is provided for each edge of the mast in the width direction.

[0035] This invention also provides a crane, including the mast lifting mechanism provided by any of the technical solutions of this invention.

[0036] The mast lifting mechanism provided by the above technical solution does not have a lifting frame. The lifting cylinder cooperates with the guide component, which is fixedly connected to the mast, so that the mast rotates when the lifting cylinder extends. When the lifting cylinder is laid flat, it is not obstructed by the guide component and can be placed flat on the turntable. Furthermore, the number of components is small, the hinge points between components are reduced, and the assembly relationship is reliable. Attached Figure Description

[0037] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0038] Figure 1 This is a front view schematic diagram of a crane provided in an embodiment of the present invention.

[0039] Figure 2 This is a top view schematic diagram of a crane provided in an embodiment of the present invention;

[0040] Figure 3 This is a left-side view of a crane provided for an embodiment of the present invention.

[0041] Figure 4 This is a schematic diagram of the mast lifting mechanism provided in an embodiment of the present invention.

[0042] Figure 5 This is a schematic diagram of another state of the mast lifting mechanism provided in an embodiment of the present invention.

[0043] Figure 6 This is an enlarged schematic diagram of the lifting cylinder of the mast lifting mechanism provided in an embodiment of the present invention.

[0044] Figure 7 This is a schematic diagram of the lifting cylinder of the mast lifting mechanism provided in an embodiment of the present invention at its longest stroke.

[0045] Figure 8 This is an enlarged schematic diagram of the guide component of the mast lifting mechanism provided in an embodiment of the present invention.

[0046] Figure 9 A schematic diagram of the guide structure of the mast lifting mechanism provided in an embodiment of the present invention.

[0047] Figure 10 This is a schematic diagram showing the connection relationship between the lifting cylinder and the pin shaft of the mast lifting mechanism provided in an embodiment of the present invention.

[0048] Figure 11 This is a schematic diagram of the lifting cylinder structure of the mast lifting mechanism provided in an embodiment of the present invention.

[0049] Figure 12 This is a schematic diagram of the hydraulic cylinder bracket structure of the mast lifting mechanism provided in an embodiment of the present invention.

[0050] Figure label:

[0051] 1. Turntable; 2. Mast; 3. Guide components; 4. Lifting cylinder; 5. Pin; 6. Cylinder bracket; 7. Angle measuring element;

[0052] 30. Slide groove; 31. First plate; 32. Second plate; 301. Guide section; 302. Transition section; 303. Limiting section;

[0053] 51. Annular inner concave part;

[0054] 61. First connecting arm; 62. Second connecting arm; 63. Connector. Detailed Implementation

[0055] The following is combined with Figures 1-12 The technical solution provided by this invention will be described in more detail below.

[0056] See Figures 1 to 3 This invention also provides a crane, including a mast lifting mechanism provided by any of the technical solutions of this invention. The mast lifting mechanism is used to rotate the mast 2 from a horizontal position by more than 90° in order to connect the main boom pull plate, thereby realizing boom lifting.

[0057] The crane also includes tracks located at the bottom of the turntable 1 to enable the crane to move. A crawler crane is a crane equipped with a traveling device, lifting device, luffing device, and slewing device on a traveling crawler chassis.

[0058] See Figures 1 to 3 The mast lifting mechanism includes a turntable 1, a mast 2, a guide 3, and a lifting cylinder 4. The mast 2 is rotatably connected to the turntable 1. The guide 3 is fixed to one end of the mast 2 near the turntable 1 and includes an open groove 30. One end of the lifting cylinder 4 is rotatably connected to the turntable 1, and the other end of the lifting cylinder 4 engages with the groove 30 and is configured to switch between two positions: within the groove 30 and disengaged from the groove 30.

[0059] Turntable 1 is the upper slewing part of the crawler crane. The turntable 1 is equipped with the operator's cab, power system, hydraulic system, main boom hinge point, mast 2 hinge point, counterweight, etc.

[0060] Mast 2 is the luffing component of the boom, and it is hinged to the turntable 1. Through mast 2, the wire rope, via pulley blocks at its head and lower sections, enables the main boom to luff. An auxiliary installation cylinder is hinged to the top of mast 2; the luffing of mast 2 and the extension / retraction of the auxiliary installation cylinder allow for self-assembly and disassembly of the main boom, facilitating relocation.

[0061] The maximum angle between mast 2 and turntable 1 is α, which is greater than 90° and approximately 107.2°. As mast 2 rotates from 0° to its maximum angle relative to turntable 1, the other end of lifting cylinder 4 is positioned at different locations on the slide groove 30 of guide member 3. When the angle between mast 2 and turntable 1 is 0°, the other end of lifting cylinder 4 is at the bottom of slide groove 30; when the angle between mast 2 and turntable 1 is α, the other end of lifting cylinder 4 is at the opening of slide groove 30.

[0062] To ensure reliable rotation of mast 2, a lifting cylinder 4 is installed at each edge along the rotation direction of mast 2, and each lifting cylinder 4 is equipped with a corresponding guide component 3. The lifting cylinders 4 and guide components 3 on both sides have the same structure; the following description will focus on one side.

[0063] Figure 4 The diagram illustrates the lifting cylinder 4 of the mast lifting mechanism extending halfway. Figure 5 This diagram illustrates the mast lifting mechanism with the lifting cylinder 4 extended to its maximum length. Figure 6 A partially enlarged schematic diagram of the lifting cylinder 4 is shown. Figure 7 The diagram illustrates the lifting cylinder 4 at its maximum length.

[0064] See Figure 8 and Figure 9 In some embodiments, the guide member 3 includes a first plate 31 and a second plate 32. The first plate 31 is fixed to one end of the mast 2 near the turntable 1; the second plate 32 is arranged parallel to the first plate 31 and is also fixed to one end of the mast 2 near the turntable 1. Both the first plate 31 and the second plate 32 include a groove 30.

[0065] The first plate 31 and the second plate 32 have the same structure. See also Figure 8 Each of the slide grooves 30 includes a guide section 301, a transition section 302, and a limiting section 303. The guide section 301 is constructed to be straight; located at the bottom of the guide section 301, the transition section 302 is constructed to be curved. The limiting section 303 is located at the end of the transition section 302 away from the guide section 301, and the limiting section 303 is parallel to the guide section 301. The transition section 302 acts as a constraint, making it difficult for the other end of the lifting cylinder 4 to slide from the limiting section 303 into the guide section 301, nor easy for it to slide from the guide section 301 into the guide section 301. This reduces the probability of the end of the lifting cylinder 4 accidentally slipping out of the slide groove 30, allowing the mast 2 to be stably placed on the turntable 1 when laid flat.

[0066] The guide component 3 adopts a double-ear plate structure, which improves structural stability. The opening end of the slide groove 30 is designed as a flared shape, which facilitates the entry of the annular inner recess 51 of the pin 5 into the slide groove. As the lifting cylinder 4 extends, the pin 5 reaches the limit position of the slide groove 30, thereby raising the mast 2.

[0067] One end of the lifting cylinder 4 is rotatably connected to the turntable 1 via a pin 5 and other components. Specifically, a cylindrical boss is fixed to the bottom of the cylinder barrel of the lifting cylinder 4, and is hinged to the cylinder support at the bottom of the turntable 1 via the cylindrical boss. The other end of the lifting cylinder 4 engages with the slide groove 30 of the guide member 3. As the lifting cylinder 4 rises and retracts, the other end of the lifting cylinder 4 moves relative to the slide groove 30. To make the engagement between the lifting cylinder 4 and the slide groove 30 more controllable and manageable, see [reference needed]. Figure 7 , Figure 10 and Figure 11In some embodiments, the mast lifting mechanism further includes a pin 5. The middle part of the pin 5 is fixedly connected to the piston rod of the lifting cylinder 4, and both ends of the pin 5 are provided with annular recesses 51. One annular recess 51 engages with the slide groove 30 of the first plate 31, and the other annular recess 51 engages with the slide groove 30 of the second plate 32. The annular recess 51 engages with the slide groove 30 and is configured to switch between two positions: the annular recess 51 is in the slide groove 30, and the annular recess 51 is disengaged from the slide groove 30.

[0068] In some embodiments, the hardness of the pin 5 is greater than that of the guide member 3 of the mast 2. During operation, the pin 5 is less prone to deformation under stress, so even after prolonged use, the shapes of both the lifting cylinder 4 and the pin 5 remain relatively intact and are not easily deformed. Therefore, even after prolonged use, the lifting cylinder 4 can still maintain planar contact with the turntable 1 in a flat position and is not prone to tilting. The stable structure and resistance to deformation of the pin 5 also ensure a secure fit between the pin 5 and the slide groove 30, allowing the slide groove 30 to consistently guide the pin 5.

[0069] See Figure 10 One pin 5 corresponds to two annular recesses 51, and each groove 30 corresponds to one annular recess 51.

[0070] See Figure 6 and Figure 12 In some embodiments, the mast lifting mechanism further includes a cylinder bracket 6, which is mounted on the turntable 1. The cylinder bracket 6 includes a limiting groove through which the lifting cylinder 4 passes, thereby limiting the rotation angle of the lifting cylinder 4 relative to the turntable 1. The cylinder bracket 6 employs a mechanical limiting structure, ensuring that when the lifting cylinder 4 rotates to its maximum position, it is directly blocked by the cylinder bracket 6, preventing further rotation.

[0071] See Figure 12 The cylinder bracket 6 specifically includes a first connecting arm 61, a second connecting arm 62, and a connector 63. The first connecting arm 61 and the second connecting arm 62 can have the same structure. The first connecting arm 61 and / or the second connecting arm 62 are constructed to be bent. This facilitates surrounding the lifting cylinder 4. One end of the first connecting arm 61 is fixedly connected to the turntable 1; one end of the second connecting arm 62 is fixedly connected to the turntable 1. The connector 63 fixes the other end of the first connecting arm 61 to the other end of the second connecting arm 62; the connector 63 includes a recess; when the lifting cylinder 4 rotates to its maximum angle with the turntable 1, the lifting cylinder 4 rests against the recess.

[0072] The operation of the lifting cylinder 4 is as follows: When the angle between the mast 2 and the turntable 1 is greater than α, the lifting cylinder 4 reaches its maximum stroke. At this time, the lifting cylinder 4 needs to retract. The pin 5 at the head of the piston rod of the lifting cylinder 4 retracts along the slide groove 30 of the guide 3. After the pin 5 disengages from the slide groove 30, it is supported by the cylinder bracket 6 welded on the turntable 1, realizing the unobstructed retraction of the piston rod of the lifting cylinder 4. The cylinder bracket 6 also serves as a guide mechanism, which can effectively orient the lifting cylinder 4 when it extends to connect with the mast 2.

[0073] When the mast 2 falls back to α (for example, 107°) and needs to be lowered, the lifting cylinder 4 extends to receive the mast 2. The guide groove 30 then engages with the annular inner recess 51 of the pin 5, thus connecting the lifting cylinder 4 with the mast 2.

[0074] In some embodiments, the mast lifting mechanism further includes an angle measuring element 7, which is installed at the hinge point between the mast 2 and the turntable 1. The angle measuring element 7 monitors the angle between the mast 2 and the turntable 1 in real time, and the control system can control the extension and retraction of the lifting cylinder 4 at a set mast 2 angle of 107°.

[0075] When the lifting cylinder 4 and the guide member 3 come into contact, the pin 5 of the piston rod of the lifting cylinder 4 is provided with an annular inner recess 51, which is stuck in the slide groove 30.

[0076] When the hydraulic system supplies oil, the piston rod of the lifting cylinder 4 extends, lifting the mast 2. The angle measuring element 7, specifically the angle sensor, detects that the angle between the mast 2 and the turntable 1 is ≥107°. At this point, the lifting cylinder 4 is at its maximum stroke position, and its tilt angle is exactly against the cylinder bracket 6. Afterward, the mast 2 can continue to tilt forward under its own weight, no longer requiring the action of the lifting cylinder 4. The lifting cylinder 4 then begins to retract, remaining against the cylinder bracket 6 throughout the retraction process.

[0077] When the crane finishes its work and the mast 2 falls, the angle sensor detects that the angle between the mast 2 and the turntable 1 reaches 107°. The piston rod of the lifting cylinder 4 extends. Due to the guidance of the cylinder bracket 6, after the piston rod extends, the pin 5 at the end of the piston rod is just stuck in the slide groove 30, realizing the connection between the lifting cylinder 4 and the mast 2. After that, the mast 2 falls back to the horizontal position slowly by relying on the lifting cylinder 4.

[0078] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of this invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A mast jacking mechanism, characterised in that, The utility model relates to a kind of jacking oil cylinder, including: Rotary table (1); Mast (2), rotatable connection with the rotary table (1); Guide piece (3), fixed to the mast (2) near the rotary table (1) one end, the guide piece (3) includes open chute (30);And Jacking oil cylinder (4), one end rotatable connection with the rotary table (1), the other end with the chute (30) cooperation and be configured as between the following two positions switching: in the chute (30), separate from the chute (30); The chute (30) includes: Guide section (301), it is configured to be straight; Transition section (302), located at the bottom of the guide section (301), and the transition section (302) is configured to be curved;And Limit section (303), located at the end of the transition section (302) away from the guide section (301), the limit section (303) is parallel with the guide section (301).

2. A mast jacking mechanism according to claim 1, characterised in that, The guide piece (3) includes: First plate (31), fixed to the mast (2) near the rotary table (1) one end;And Second plate (32), parallel arrangement with the first plate (31), and also fixed to the mast (2) near the rotary table (1) one end; The first plate (31) and the second plate (32) all include the chute (30).

3. A mast jacking mechanism according to claim 1, characterised in that, When the jacking oil cylinder (4) rotates to adhere to the rotary table (1), the other end of the jacking oil cylinder (4) is located in the limit section (303) of the chute (30).

4. A mast jacking mechanism according to claim 2, characterised in that, Further including: Pin shaft (5), the middle part of the pin shaft (5) is fixedly connected with the piston rod of the jacking oil cylinder (4), and the two ends of the pin shaft (5) are provided with annular recess (51), one of the annular recess (51) is matched with the chute (30) of the first plate (31), and the other annular recess (51) is matched with the chute (30) of the second plate (32);The annular recess (51) is matched with the chute (30) and is configured to switch between the following two positions: the annular recess (51) is located in the chute (30), the annular recess (51) is separated from the chute (30).

5. The mast jacking mechanism of claim 1, wherein, Further including: Oil cylinder bracket (6), installed on the rotary table (1), the oil cylinder bracket (6) includes limit slot, the jacking oil cylinder (4) passes through the limit slot, and the rotation angle of the jacking oil cylinder (4) relative to the rotary table (1) is limited by the limit slot.

6. A mast jacking mechanism according to claim 5, characterised in that, The oil cylinder bracket (6) includes: First connecting arm (61), one end fixedly connected with the rotary table (1); Second connecting arm (62), one end fixedly connected with the rotary table (1);And Connecting piece (63), the other end of the first connecting arm (61) and the other end of the second connecting arm (62) are fixedly connected;The connecting piece (63) includes recess;When the jacking oil cylinder (4) rotates to the maximum angle with the rotary table (1), the jacking oil cylinder (4) leans in the recess.

7. A mast jacking mechanism according to claim 6, characterised in that, When the jacking oil cylinder (4) rotates to the maximum angle with the rotating platform (1), the jacking oil cylinder (4) is retracted to be separated from the sliding groove (30).

8. A mast jacking mechanism according to claim 6, characterised in that, The first connecting arm (61) and / or the second connecting arm (62) are configured to be bent.

9. The mast jacking mechanism of claim 1, wherein, Further comprising: An angle measuring element (7) is installed at the hinge point position of the mast (2) and the rotating platform (1); the angle measuring element (7) monitors the included angle of the mast (2) and the rotating platform (1) in real time; A control system is electrically connected with the angle detecting element; the control system controls the extension and retraction of the jacking oil cylinder (4) when the included angle measured by the angle measuring element (7) is a set value.

10. The mast jacking mechanism of claim 1, wherein, The number of the jacking oil cylinder (4) is two, and one jacking oil cylinder (4) is arranged on each edge of the mast (2) in the width direction.

11. A crane, characterized in that The mast jacking mechanism comprises the mast jacking mechanism according to any one of claims 1-10.

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