CN220972224U - Power unit assembling tool - Google Patents

Abstract

The utility model relates to the technical field of power unit assembly, and particularly discloses a power unit assembly tool which comprises a shell, a fixed block, a clamping assembly and an arc-shaped lifting plate, wherein the fixed block and the clamping assembly are at least partially positioned in the shell, the fixed block is used for supporting the clamping assembly, the clamping assembly is used for clamping or releasing a cylinder sleeve of a power unit, relative movement can occur between the shell and the fixed block, when the shell moves relative to the fixed block, the clamping assembly can clamp or release the cylinder sleeve, the arc-shaped lifting plate is positioned outside the shell and fixedly connected with the fixed block, and a plurality of lifting holes are formed in the arc-shaped lifting plate along the radian direction of the arc-shaped lifting plate. The clamping assembly clamps the cylinder sleeve to realize that the piston connecting rod group is pre-installed in the cylinder sleeve and is integrally installed in the engine, and meanwhile, the arc-shaped lifting plate is arranged, a plurality of lifting holes are formed in the radian direction, the piston connecting rod group is lifted through connecting different lifting holes, and the requirements of different machine types and various installation angles can be met during installation, so that the application scene of the piston connecting rod group is widened.

Description

Power unit assembling tool

Technical Field

The utility model relates to the technical field of power unit assembly, in particular to a power unit assembly tool.

Background

When the power unit of the engine is assembled, all the parts are assembled and fixed into a whole through bolts by split tools, so that the assembly is completed. However, when the power unit of the large engine is assembled, the piston rod group cannot be directly assembled or disassembled from the cylinder liner due to the excessively large shaft diameter of the connecting rod.

In this regard, the prior art provides a piston connecting rod assembly fixture, this frock is through setting up a plurality of toper pieces along the radial of cylinder liner, makes toper piece remove and with the cylinder liner butt through the slip slider, lean on the friction effect of toper piece and cylinder liner to fix the cylinder liner to form a whole with piston connecting rod assembly preassembly in the cylinder liner and assemble the engine again, thereby also improved the assembly efficiency of power unit when solving above-mentioned problem. But this frock only can vertical hoisting in the use, consequently can only satisfy the assembly demand of in-line engine, can't better adaptation V type, W type engine's assembly demand, and applicable scene is less.

Disclosure of utility model

The utility model aims to provide a power unit assembling tool which solves the problem that the existing tool is less in applicable scene because the existing tool can only be vertically hoisted.

The utility model provides a power unit assembling tool which comprises a shell, a fixed block, a clamping assembly and an arc-shaped lifting plate, wherein the fixed block and the clamping assembly are at least partially positioned in the shell, the fixed block is used for supporting the clamping assembly, the clamping assembly is used for clamping or releasing a cylinder sleeve of a power unit, relative movement can occur between the shell and the fixed block, when the shell moves relative to the fixed block, the clamping assembly can clamp or release the cylinder sleeve, the arc-shaped lifting plate is positioned outside the shell and fixedly connected with the fixed block, and a plurality of lifting holes are formed in the arc-shaped lifting plate along the radian direction of the arc-shaped lifting plate.

As the preferential technical scheme of power unit assembly tool, the clamping assembly includes a plurality of jack catchs, and a plurality of jack catchs evenly set up in the shell, and the jack catchs are provided with location portion and clamping part, and location portion sets up between shell and fixed block, and the clamping part is used for centre gripping cylinder liner.

As the preferential technical scheme of power unit assembly tool, the jack catch includes clamping state and release state, and the jack catch still includes operating portion, and operating portion sets up between location portion and clamping part, and operating portion is provided with the arch towards the direction of shell, and the inside wall setting of shell is used for with protruding complex recess, and the jack catch is in clamping state, and the arch breaks away from the recess, and the jack catch can the centre gripping cylinder liner, and the jack catch is in when release state, protruding and recess cooperation, jack catch release cylinder liner.

As a preferable technical scheme of the power unit assembling tool, the groove is provided with a first limiting wall and a first leading-in wall, the bulge is provided with a second limiting wall and a second leading-in wall, and when the clamping jaw is in a release state, the second limiting wall is contacted with the first limiting wall; when the clamping jaw is in a clamping state, the top wall of the bulge is abutted with the inner side wall of the shell; the second leading-in wall and the first leading-in wall are used for enabling the protrusion to be separated from the groove when the shell moves relative to the fixed block.

As a preferred technical solution of the power unit assembling tool, the clamping portion comprises a bearing wall and a first mating wall which are adjacently arranged, the bearing wall is in contact with the bottom wall of the flange of the cylinder sleeve, and the first mating wall is in contact with the outer side wall of the flange.

As the preferable technical scheme of the power unit assembling tool, the fixing block is provided with a clamping locating hole and a releasing locating hole, the clamping locating hole is positioned below the releasing locating hole, the locating pin penetrates through the shell and is connected with the clamping locating hole when the clamping jaw is in a clamping state, and the locating pin penetrates through the shell and is connected with the releasing locating hole when the clamping jaw is in a releasing state.

As the preferable technical scheme of the power unit assembling tool, the power unit assembling tool further comprises a fixing bolt, wherein the fixing bolt penetrates through the fixing block, and the fixing bolt is used for being connected with a piston of the power unit.

As the preferable technical scheme of the power unit assembling tool, the arc-shaped hanging plate is provided with a yielding groove, and the head of the fixing bolt is arranged in the yielding groove.

As the preferred technical scheme of the power unit assembling tool, the power unit assembling tool further comprises at least two handles, wherein each handle comprises a connecting shaft and a sleeve, the connecting shaft is fixedly connected with the shell, and the sleeve is rotatably sleeved on the connecting shaft.

As the preferred technical scheme of the power unit assembling tool, the power unit assembling tool further comprises an insert, wherein the insert is welded with the shell, and the connecting shaft is fixedly connected with the insert.

The beneficial effects of the utility model are as follows:

The utility model provides a power unit assembling tool which comprises a shell, a fixed block, a clamping assembly and an arc-shaped lifting plate, wherein the fixed block and the clamping assembly are at least partially positioned in the shell, the fixed block is used for supporting the clamping assembly, the clamping assembly is used for clamping a cylinder sleeve of a power unit, the shell and the fixed block can move relatively, when the shell moves relative to the fixed block, the clamping assembly can clamp the cylinder sleeve, the arc-shaped lifting plate is positioned outside the shell and fixedly connected with the fixed block, and a plurality of lifting holes are formed in the arc-shaped lifting plate along the radian direction of the arc-shaped lifting plate. Through clamping assembly centre gripping cylinder liner, also can realize in the cylinder liner with power unit's piston connecting rod group to pack into the engine as a whole in advance, set up curved hanger plate simultaneously and set up a plurality of lifting holes along the radian direction, hoist through connecting different lifting holes, can satisfy the demand of different models and multiple installation angle when the installation, thereby widen its application scenario.

Drawings

FIG. 1 is a schematic view of a power unit assembly tool according to an embodiment of the present utility model;

FIG. 2 is a cross-sectional view of a power unit assembly tool according to an embodiment of the present utility model;

FIG. 3 is an enlarged view of a portion A of FIG. 2;

FIG. 4 is a schematic view of a power unit assembly tool coupled to a cylinder liner according to an embodiment of the present utility model.

In the figure:

100. Cylinder sleeve;

1. A housing; 2. a handle; 3. a positioning pin; 4. an arc-shaped hanging plate; 5. a fixing bolt; 6. a fixed block; 7. a claw;

11. a first limiting wall; 12. a first lead-in wall;

41. a hoisting hole;

71. The second limiting wall; 72. a second lead-in wall; 73. a load-bearing wall; 74. a first mating wall; 75. a second mating wall.

Detailed Description

The following description of the embodiments of the present utility model will be made more apparent and fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first location" and "second location" are two distinct locations and wherein the first feature is "above," "over" and "over" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is level above the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood as appropriate by those of ordinary skill in the art.

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.

As shown in fig. 1-4, the present utility model provides a power unit assembly tool, comprising a housing 1, a fixed block 6, a clamping assembly and an arc-shaped hanging plate 4, wherein at least part of the fixed block 6 is positioned in the housing 1, the fixed block 6 penetrates through the housing 1, and the housing 1 can move relative to the fixed block 6. At least part of a clamping assembly is arranged in the housing 1, the clamping assembly being adapted to clamp or release the cylinder liner 100 of the power unit, the fixing block 6 being adapted to hold the clamping assembly, the clamping assembly being adapted to clamp or release the cylinder liner 100 of the power unit when the housing 1 is moved relative to the fixing block 6. The arc-shaped hanging plate 4 is fixedly connected with the fixed block 6 in a bolt connection or a welding connection mode, and in the embodiment, the arc-shaped hanging plate 4 is preferably connected with the fixed block 6 through welding. The arc-shaped hanger plate 4 is provided with a plurality of hanger holes 41 along the arc direction thereof. Through clamping assembly cylinder liner 100, also can realize loading in advance the cylinder liner 100 with the piston connecting rod group of power unit to regard as an integral loading engine, set up curved hanger plate simultaneously and set up a plurality of lifting holes 41 along the radian direction, hoist through connecting different lifting holes 41, can satisfy the demand of different models and multiple installation angle when the installation, thereby widen its application scenario.

In particular, as shown in fig. 2-4, the clamping assembly comprises a plurality of jaws 7, the number of jaws 7 may be 2, 3 or 4. In the present embodiment, the number of the claws 7 is preferably 4. The housing 1 is preferably a circular stepped tubular member with a small end at the upper portion and a large end at the lower portion. The 4 claws 7 are each provided in the large end of the housing 1 and are uniformly provided in the circumferential direction of the housing 1. The fixing block 6 is preferably an inverted T-shaped part in cross section, one part of the fixing block 6 is arranged in the shell 1, and the other part of the fixing block 6 penetrates through and extends out of the small end of the shell 1 and then is welded with the arc-shaped hanging plate 4. The claw 7 is provided with a positioning portion, an operating portion, and a clamping portion. The locating part sets up between fixed block 6 and shell 1, and fixed block 6 bearing locating part to avoid jack catch 7 to drop from shell 1. The operation part is vertically connected with the positioning part, and the bottom of the operation part is provided with a clamping part. The clamping portion is used to clamp the cylinder liner 100. The clamping portion is provided with a carrying wall 73, a first mating wall 74 and a second mating wall 75, the first mating wall 74 and the second mating wall 75 being arranged in parallel, the carrying wall 73 being arranged between the first mating wall 74 and the second mating wall 75, the carrying wall 73 being arranged adjacent to the first mating wall 74 and perpendicular to the first mating wall 74. As is known in the art, the end of the liner 100 is provided with a flange that extends radially outwardly of the body of the liner 100. The bearing wall 73 is in contact with the bottom wall of the flange of the cylinder liner 100 and is used for bearing the cylinder liner 100, and the first mating wall 74 is in contact with the outer side wall of the flange of the cylinder liner 100 and is used for preventing the cylinder liner 100 from shaking axially. A certain gap exists between the second mating wall 75 and the outer side wall of the cylinder liner 100 to reduce the difficulty of assembly. A limit flange is further provided on the clamping portion, and the limit flange can contact with the top end of the cylinder liner 100 to limit the axial position of the cylinder liner 100. The cylinder sleeve 100 is clamped through the combined action of the clamping claws 7, so that the piston connecting rod group of the power unit can be pre-assembled and then lifted and installed at a specific angle, and the power unit is suitable for engines with various cylinder angles.

Further, as shown in fig. 2-3, the claw 7 comprises a clamping state and a releasing state, when clamping the cylinder liner 100, the claw 7 is firstly in the releasing state, and after the clamping assembly is sleeved into the cylinder liner 100, the claw 7 is switched to the clamping state to clamp the cylinder liner 100. In the present embodiment, the state switching of the claw 7 can be achieved as follows. The operating portion of the claw 7 can be in contact with the inner side wall of the housing 1, the operating portion is provided with a protrusion toward the direction of the housing 1, and the inner side wall of the housing 1 is provided with a groove for being matched with the protrusion. When the clamping jaws 7 are in a release state, the protrusions are matched with the grooves, and the radial distance between the two opposite clamping jaws 7 is increased through the matching of the protrusions and the grooves, so that the clamping assembly can be sleeved into the cylinder sleeve 100. When the jaws 7 are in the clamped state, the protrusions are disengaged from the grooves, thereby reducing the radial distance of the two opposite jaws 7 to clamp the cylinder liner 100.

Still further, as shown in fig. 3, the groove includes a first limiting wall 11, a bottom wall and a first guiding wall 12, the first limiting wall 11 is disposed along a horizontal direction, the bottom wall is disposed along a vertical direction, the first guiding wall 12 is disposed at an obtuse angle with the bottom wall, and the first guiding wall 12 is disposed above the bottom wall. The protrusion includes a second limiting wall 71, a top wall and a second guiding wall 72, the second limiting wall 71 is disposed along a horizontal direction, the top wall is disposed along a vertical direction, the second guiding wall 72 is disposed at an obtuse angle with the top wall, and the angle between the first guiding wall 12 and the bottom wall is equal in value, and the second guiding wall 72 is disposed above the top wall. The second lead-in wall 72 and the first lead-in wall 12 serve to disengage the protrusion from the recess when the housing 1 is moved relative to the fixed block 6. When the claw 7 is required to be in a release state, the shell 1 is lifted upwards, the groove moves upwards relative to the protrusion until the protrusion is aligned with the groove, and at the moment, the claw 7 can be stirred to move towards the direction of the groove, so that the protrusion is matched with the groove, the second limiting wall 71 is contacted with the first limiting wall 11, the distance between the two opposite claws 7 along the radial direction is increased, and the claws 7 are in the release state. The height of the protrusion is smaller than or equal to the depth of the groove, so that interference of the clamping assembly in the process of sleeving the cylinder sleeve 100 caused by the fact that the clamping jaws 7 are not released in place is avoided. When the jaws 7 are required to be in a clamped state, the housing 1 is pressed downwards, so that the housing 1 moves downwards relative to the fixed block 6, i.e. the grooves move downwards relative to the protrusions. Since the recess and the protrusion are in a fitted state at this time, during the downward pressing of the casing 1, the protrusion and the recess are relatively dislocated in the direction of the first introduction wall 12, i.e., the protrusion moves away from the recess while moving upward with respect to the recess, so that the radial distance between the opposite jaws 7 is reduced to clamp the cylinder liner 100.

Specifically, as shown in fig. 3, in order to enhance the structural strength of the assembly tool, two bosses are uniformly provided on the claw 7. Two grooves are correspondingly arranged on the inner side wall of the shell. In this embodiment, one of the grooves is complete and the other groove is provided with only a first lead-in wall 12, which can likewise cooperate with the boss, in order to achieve the clamping and release action of the jaws 7, due to the weight and size constraints. In other embodiments, the positions or the number of the bosses can be adjusted according to different actual conditions, and the positions or the number of the grooves can be adaptively adjusted to meet the use requirements.

Optionally, a clamping positioning hole and a releasing positioning hole are formed in the fixing block 6 along the vertical direction, and the clamping positioning hole is located below the releasing positioning hole. When the claw 7 is switched from the released state to the clamped state, the housing moves downwards until the claw 7 is switched to the clamped state. The shell 1 is connected with a positioning pin 3, and the positioning pin 3 penetrates through the shell 1 and is connected with the clamping positioning hole, so that the shell is ensured to move downwards to be in place, namely, the clamping jaw 7 is in a clamping state, the shell 1 is locked after the positioning pin 3 is connected with the clamping positioning hole, and the shell 1 and the clamping jaw 7 do not move relatively in the installation process, so that the clamping force of the clamping assembly on the cylinder sleeve 100 is ensured to be constant. If the positioning pin 3 is not aligned with the clamping positioning hole, the shell moves downwards to be not in place, at this time, the positioning pin 3 cannot be connected with the clamping positioning hole, and the clamping force of the clamping jaw 7 on the cylinder sleeve 100 is insufficient. When the clamping state of the claw 7 is switched to the release state, the shell moves upwards until the claw 7 is switched to the release state, and the positioning pin 3 penetrates through the shell 1 to be connected with the release positioning hole, so that the shell moves upwards in place, namely, the claw 7 is in the release state, the shell 1 is locked after the positioning pin 3 is connected with the release positioning hole, and the shell 1 and the claw 7 do not move relatively in the process of sleeving the cylinder sleeve 100, so that the claw 7 is ensured to be released in place. If the positioning pin 3 is not aligned with the release positioning hole, the claw 7 may not be released in place, and at this time, the positioning pin 3 cannot be connected with the release positioning hole, and in the process of sleeving the cylinder liner 100 with the clamping assembly, the clamping portion and the flange of the cylinder liner 100 are likely to interfere with each other, which is difficult to install.

It should be noted that, in other embodiments, the following modifications may be made based on the above scheme: the first lead-in wall 12 is disposed below the bottom wall and the second lead-in wall 72 is disposed below the top wall. And simultaneously, the clamping positioning hole is arranged above the release positioning hole. Correspondingly, when the claw 7 is required to be in a release state, the shell 1 is pressed downwards until the positioning pin 3 is aligned with the release positioning hole, and the positioning pin 3 is inserted into the release positioning hole. When the claw 7 is required to be in a clamping state, the shell 1 is lifted upwards until the positioning pin 3 is aligned with the clamping positioning hole, and the positioning pin 3 is inserted into the clamping positioning hole, and the related implementation principle is described in detail in the above scheme, and will not be described in detail herein.

Further, as shown in fig. 2 and 4, the power unit assembling tool further includes a fixing bolt 5, and the fixing bolt 5 passes through the fixing block 6 and protrudes out of the housing 1. After the clamping assembly clamps the cylinder sleeve 100, a piston connecting rod group is assembled into the cylinder sleeve 100, and the fixing bolt 5 is used for being connected with a piston so as to prevent the piston connecting rod group from being separated from the cylinder sleeve 100 in the hoisting process. The head of the fixing bolt 5 extends out of the fixing piece, a yielding groove is formed in the arc-shaped hanging plate 4, the head of the fixing bolt 5 is arranged in the yielding groove, and a user can rotate the head of the fixing bolt 5 through an operation space at the yielding groove to enable the fixing bolt to be connected with the piston.

Optionally, for ease of handling, the power unit assembly tool further comprises at least two handles 2, the two handles 2 being symmetrically arranged on the housing 1. The handle 2 comprises a connecting shaft and a sleeve, the connecting shaft is fixedly connected with the shell 1, and the sleeve is rotatably sleeved on the connecting shaft. During use, a user can more conveniently lift or press the housing 1 by means of the handle 2. Meanwhile, the sleeve is sleeved on the connecting shaft, so that a user can conveniently exert force from various angles, and the use comfort is improved.

Optionally, since the inner side wall of the housing 1 is provided with a groove, which results in a local thickness reduction of the housing 1, in order to avoid a situation that the handle 2 is mounted to a position where the thickness is thin, which results in insufficient strength to cause damage in lifting or pressing, an insert is provided at the connection point of the handle 2 and the housing 1, the insert is welded with the housing 1, and the connecting shaft is fixedly connected with the insert, and in this embodiment, the connecting shaft is preferably in threaded connection with the insert. Through setting up the insert, will comparatively concentrate the load and scatter, improved the local structural strength of tie point position, avoid appearing damaging the condition such as in the use.

Specifically, as shown in fig. 4, when assembling is performed using the power unit assembling tool in the present embodiment. The positioning pin 3 is pulled out first and the handle 2 is lifted upwards, so that the shell 1 moves upwards relative to the clamping jaws 7 until the positioning pin 3 is aligned with the release positioning hole, the positioning pin 3 is inserted into the release positioning hole to lock the position of the shell 1, the clamping jaws 7 are shifted to move towards the corresponding grooves respectively, and therefore the distance between the two opposite clamping jaws 7 is increased. The claw assembly is sleeved on the cylinder sleeve 100, the positioning pin 3 is pulled out from the release positioning hole, the handle 2 is pressed downwards, the shell 1 moves downwards relative to the claws 7, meanwhile, the protrusions on the claws 7 and the grooves on the shell 1 are relatively staggered, the distance between the two opposite claws 7 is reduced, the cylinder sleeve 100 is clamped, and when the positioning pin 3 is aligned with the clamping positioning hole, the positioning pin 3 is inserted into the clamping positioning hole to lock the position of the shell 1. The piston connecting rod is assembled into the cylinder liner 100, and the fixing bolt 5 is connected with the top of the piston, so that the position of the piston in the cylinder liner 100 is fixed. After the piston connecting rod group is assembled to the cylinder sleeve 100, the corresponding lifting holes 41 on the arc-shaped lifting plate 4 are selected according to the type of the engine on which the power unit is required to be installed for lifting so as to lift the power unit to the engine at a specific angle for installation. After the power unit is connected with the engine, the fixing bolt 5 connected with the piston is loosened, the locating pin 3 in the clamping locating hole is pulled out, the handle 2 is lifted upwards, the claw 7 is shifted to enable the distance between the two opposite claws 7 to be increased, and therefore the power unit assembling tool is detached from the cylinder sleeve 100.

It is to be understood that the above examples of the present utility model are provided for clarity of illustration only and are not limiting of the embodiments of the present utility model. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.

Claims (10)

1. The power unit assembling tool is characterized by comprising a shell (1), a fixed block (6), a clamping assembly and an arc-shaped hanging plate (4), wherein the fixed block (6) and the clamping assembly are at least partially positioned in the shell (1);

The fixed block (6) is used for supporting the clamping assembly, the clamping assembly is used for clamping or releasing a cylinder sleeve (100) of the power unit, relative movement can occur between the shell (1) and the fixed block, and when the shell (1) moves relative to the fixed block (6), the clamping assembly can clamp or release the cylinder sleeve (100);

The arc-shaped hanging plate (4) is located outside the shell (1) and fixedly connected with the fixed block (6), and a plurality of hanging holes (41) are formed in the arc-shaped hanging plate (4) along the radian direction of the arc-shaped hanging plate.

2. The power unit assembling tool according to claim 1, wherein the clamping assembly comprises a plurality of jaws (7), the plurality of jaws (7) are uniformly arranged in the housing (1), the jaws (7) are provided with positioning portions and clamping portions, the positioning portions are arranged between the housing (1) and the fixing blocks (6), and the clamping portions are used for clamping the cylinder liners (100).

3. The power unit assembling tool according to claim 2, wherein the claw (7) comprises a clamping state and a releasing state, the claw (7) further comprises an operation portion, the operation portion is arranged between the positioning portion and the clamping portion, a protrusion is arranged on the operation portion towards the direction of the housing (1), a groove for being matched with the protrusion is arranged on the inner side wall of the housing (1), when the claw (7) is in the clamping state, the protrusion is separated from the groove, the claw (7) can clamp the cylinder sleeve (100), and when the claw (7) is in the releasing state, the protrusion is matched with the groove, and the claw (7) releases the cylinder sleeve (100).

4. A power unit assembly tool according to claim 3, wherein the recess is provided with a first limiting wall (11) and a first lead-in wall (12), the projection is provided with a second limiting wall (71) and a second lead-in wall (72), the second limiting wall (71) being in contact with the first limiting wall (11) when the claw (7) is in the released state; when the clamping jaw (7) is in a clamping state, the top wall of the bulge is abutted with the inner side wall of the shell (1); the second lead-in wall (72) and the first lead-in wall (12) are used for enabling the protrusion to be separated from the groove when the shell (1) moves relative to the fixed block (6).

5. A power unit assembly tool according to claim 3, wherein the clamping portion comprises an adjacently arranged carrier wall (73) and a first mating wall (74), the carrier wall (73) being in contact with a bottom wall of a flange of the cylinder liner (100), the first mating wall (74) being in contact with an outer side wall of the flange.

6. A power unit assembling tool according to claim 3, wherein the fixing block (6) is provided with a clamping locating hole and a releasing locating hole, the clamping locating hole is located below the releasing locating hole, the locating pin (3) penetrates through the shell (1) and is connected with the clamping locating hole when the claw (7) is in a clamping state, and the locating pin (3) penetrates through the shell (1) and is connected with the releasing locating hole when the claw (7) is in a releasing state.

7. The power unit assembly tool according to any one of claims 1-6, further comprising a fixing bolt (5), said fixing bolt (5) passing through said fixing block (6), said fixing bolt (5) being for connection with a piston of said power unit.

8. The power unit assembly tool according to claim 7, characterized in that the arc-shaped hanger plate (4) is provided with a relief groove, in which the head of the fixing bolt (5) is arranged.

9. The power unit assembly tool according to any one of claims 1-6, further comprising at least two handles (2), said handles (2) comprising a connecting shaft and a sleeve, said connecting shaft being fixedly connected to said housing (1), said sleeve being rotatably sleeved on said connecting shaft.

10. The power unit assembly tool according to claim 9, further comprising an insert welded to the housing (1), the connecting shaft being fixedly connected to the insert.