CN220748998U - Engineering machinery power output device - Google Patents

Abstract

The application discloses engineering machine tool power take off, include: the device comprises a main shaft, a transmission piece, a box body, an end cover, an oil seal, a dust-proof cover and a dust-proof ring. Wherein the transmission member is connected to a power source; the transmission part is coaxially and fixedly arranged on the main shaft; the box body is formed with an installation space and a perforation penetrating through the installation space along the direction of the rotation axis; the end cover is fixedly arranged at one end of the box body; the inside of the end cover is provided with a mounting hole communicated with the mounting space; the main shaft is in rotary connection with the box body and the end cover; the dust-proof cover is formed on or fixedly installed at one end of the end cover; the dust ring is arranged on the dust-separating cover; the dustproof sleeve is sleeved on the main shaft; the dust-proof cover is provided with a through hole; the oil seal is positioned between the box body and the dust-proof cover; the dust ring is fixedly arranged in the through hole of the dust-proof cover. The beneficial point of the application lies in: the engineering mechanical power output device ensures the sealing performance of the oil seal under the working environment with much dust.

Description

Engineering machinery power output device

Technical Field

The application relates to the technical field of engineering machinery, in particular to a power output device of engineering machinery.

Background

For a construction machine such as a drill carriage, a hydraulic drill carriage, or the like, a mining machine, or the like, a transmission for outputting torque is generally provided. The box body of the transmission device is internally provided with transmission parts such as gears, belt wheels, chain wheels and the like which are connected with power sources such as motors, hydraulic motors and the like, the transmission parts are driven to rotate in a gear transmission mode, a chain transmission mode, a belt transmission mode and the like, and then the transmission parts drive a main shaft to rotate, so that power is output through the main shaft. Lubricating oil is generally injected into the box body to lubricate transmission parts and the like in the box body. When the transmission device is used for engineering machinery, lubricating oil and the outside are often separated by arranging an oil seal between the box body and the main shaft. However, the use environment of the equipment such as the drill jumbo is often dusty, and the oil seal is easy to wear to influence the sealing effect, so that the oil leakage of the box body is serious. The rotary power head driving the drill rod to rotate on equipment such as a rock drilling rig and the like is the problem of oil leakage of the box body.

In the related art, chinese patent publication No. CN210174540U discloses a split double-row sprocket shaft, which uses double oil seals to secure a sealing effect. However, the related art does not give any technical teaching on how to solve the problem of serious oil seal abrasion of engineering machinery in a dusty severe environment.

Disclosure of Invention

The content of the present application is intended to introduce concepts in a simplified form that are further described below in the detailed description. The section of this application is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

To solve the technical problems mentioned in the background section above, some embodiments of the present application provide a power output apparatus for a construction machine, including: the device comprises a main shaft, a transmission piece, a box body, an end cover, an oil seal, a dust-proof cover and a dust-proof ring.

The transmission piece is connected to a power source to rotate around a rotation axis under the driving of the power source; the transmission part is coaxially and fixedly arranged on the main shaft so as to drive the main shaft to rotate when rotating; the box body is provided with an installation space for placing the transmission part and a perforation penetrating through the installation space along the direction of the rotation axis; the end cover is fixedly arranged at one end of the box body along the direction of the rotation axis; the inside of the end cover is provided with a mounting hole communicated with the mounting space; one end of the main shaft passes through the perforation and the mounting hole along the direction of the rotation axis to form rotation connection with the box body and the end cover around the rotation axis; the dust-proof cover is formed or fixedly arranged at one end of the end cover far away from the box body; the dust ring is arranged on the dust-separating cover; the dustproof sleeve is sleeved on the main shaft to isolate the main shaft from the dust-isolating cover; the dust-proof cover is provided with a through hole; the through hole penetrates through the dust-proof cover along the direction of the rotation axis so as to enable the main shaft to penetrate through and form rotary connection with the main shaft; each oil seal is positioned between the box body and the dust-proof cover along the direction of the rotation axis; the dust ring is fixedly arranged in the through hole of the dust-proof cover to seal the mounting hole.

Further, the construction machine power output apparatus further includes: and a blocking cover. Wherein, the baffle cover is fixedly arranged at one end of the dust-proof cover far away from the end cover; the baffle cover is provided with a shaft hole for the spindle to pass through; the dust ring is positioned between the dust separation cover and the baffle cover along the direction of the rotation axis so as to limit the movement of the dust ring along the direction of the rotation axis through the baffle cover.

Further, the dust-proof cover is provided with in order along the rotation axis direction: the connecting part and the mounting part. Wherein, the connecting part is arranged at one end of the dust-proof cover close to the end cover; the retaining cover is fixedly connected to the mounting part; the through hole penetrates through the connecting part and the mounting part, and the dust ring is positioned in the part of the through hole positioned in the mounting part; the aperture of the through hole at the connection portion is smaller than the aperture at the mounting portion.

Further, the shielding cover is at least partially positioned in the extension range of the through hole at the mounting part along the rotation axis direction so as to prevent the dust ring from being removed from the through hole.

Further, the aperture of the shaft hole is larger than the shaft diameter of the spindle passing through the shaft hole part so that the spindle and the baffle cover are arranged at intervals; the aperture of the through hole at the connecting part is larger than the shaft diameter of the main shaft passing through the connecting part.

Further, at least one oil seal is in contact with an end face of the connecting portion near one end of the end cap to restrict movement of the oil seal in the direction of the rotational axis.

Further, at least one oiling channel is arranged on the dust-proof cover; one end of the oiling channel is communicated with the outside of the dust-proof cover; the other end of the oiling channel is communicated with the through hole.

Further, the part of the through hole communicated with the oil injection channel is positioned between the oil seal and the dust ring.

Further, the end of the oil filling passage remote from the through hole extends in a direction perpendicular or oblique to the rotation axis.

Further, the power output apparatus of the construction machine further includes: and a grease nipple. Wherein, the grease nipple is detachably arranged on the dust-proof cover; the grease nipple is in one-to-one correspondence with the grease filling channels, and is embedded into one end, far away from the through hole, of the grease filling channel corresponding to the grease nipple so as to seal the grease filling channel.

The beneficial effects of this application lie in: the engineering mechanical power output device can ensure the sealing performance of the oil seal in working environments with high dust and dust.

More specifically, some embodiments of the present application may have the following specific benefits:

according to the power output device of the engineering machinery, the mode that a plurality of oil seals are arranged on the end cover is adopted to prevent external impurities from entering the installation space, so that the possibility of lubricating oil deterioration in the installation space is reduced. And the dust-proof ring is arranged on the dust-proof cover to further prevent dust from entering the mounting hole, so that the tightness of each oil seal is ensured. Even if the dust ring is damaged, the end part of the end cover is blocked by the dust separation cover, so that the possibility that the oil seal contacts dust is reduced. The engineering machinery with the engineering machinery power output device can be used for a period of time, so that the dust ring can be replaced after the shutdown. Thereby further ensuring the sealing performance of the oil seal.

The shielding cover is arranged to limit the axial movement of the dustproof ring, so that the dustproof ring is tightly contacted with the dust-separating cover, and the isolation and sealing effects of the dustproof ring on external impurities are ensured.

By arranging the oiling channel, each oil seal can be conveniently lubricated, and the possibility of abrasion is reduced. And part oiling passageway communicates to between oil blanket and the dust ring, can lubricate the dust ring, reduces the wearing and tearing of the terminal surface of dust ring contact dust separation lid of main shaft rotation in-process.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, are included to provide a further understanding of the application and to provide a further understanding of the application with regard to the other features, objects and advantages of the application. The drawings of the illustrative embodiments of the present application and their descriptions are for the purpose of illustrating the present application and are not to be construed as unduly limiting the present application.

In addition, the same or similar reference numerals denote the same or similar elements throughout the drawings. It should be understood that the figures are schematic and that elements and components are not necessarily drawn to scale.

In the drawings:

FIG. 1 is a cross-sectional view of a work machine power take-off according to one embodiment of the present application;

FIG. 2 is a partial enlarged view at B in FIG. 1;

fig. 3 is a partial enlarged view at a in fig. 1.

Meaning of the reference numerals in the drawings:

100. a power take-off of the construction machine;

110. a main shaft;

120. a transmission member;

130. a case; 131. an installation space; 132. perforating;

140. an end cap; 141. a mounting hole; 142. an oiling channel;

150. an oil seal; 151. a grease chamber 151;

160. a dust-proof cover; 161. a through hole; 162. a connection part; 163. a mounting part;

170. a dust ring;

180. a blocking cover; 181. A shaft hole;

190. a grease nipple; 191. A plug;

a1, a rotation axis.

Detailed Description

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete. It should be understood that the drawings and embodiments of the present disclosure are for illustration purposes only and are not intended to limit the scope of the present disclosure.

It should be noted that, for convenience of description, only the portions relevant to the present application are shown in the drawings. Embodiments of the present disclosure and features of embodiments may be combined with each other without conflict.

It should be noted that references to "one", "a plurality" and "a plurality" in this disclosure are intended to be illustrative rather than limiting, and those of ordinary skill in the art will appreciate that "one or more" is intended to be understood as "one or more" unless the context clearly indicates otherwise.

The present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Referring to fig. 1 to 3, a construction machine power output apparatus 100 of the present application includes: spindle 110, driving medium 120, case 130, end cap 140, oil seal 150, dust cap 160, and dust ring 170.

Wherein, the transmission member 120 is connected to a power source to rotate around the rotation axis a1 under the driving of the power source. The driving member 120 may be a gear, a pulley, a sprocket, etc., and the power source may be coupled to the driving member 120 by way of a gear drive, a belt drive, a chain drive, etc. The transmission member 120 is coaxially and fixedly arranged on the main shaft 110 to drive the main shaft 110 to rotate when rotating, namely, the main shaft 110 is driven by a power source to rotate so as to output torque to a part (such as a drill rod for rock drilling operation) connected with the power output device on the engineering machinery.

The case 130 is formed with an installation space 131 in which the driving member 120 is placed and a penetration hole 132 penetrating the installation space 131 in the direction of the rotation axis a 1. The end cap 140 is fixedly disposed at one end of the case 130 in the direction of the rotation axis a 1. The end cap 140 is provided therein with a mounting hole 141 communicating with the mounting space 131. One end of the main shaft 110 passes through the through hole 132 and the mounting hole 141 in the direction of the rotation axis a1 to be rotatably coupled with the case 130 and the cap 140 about the rotation axis a 1. Thereby mounting the main shaft 110 between the case 130 and the end cap 140. The installation space 131 is filled with lubricating oil or grease for lubricating the box main shaft 110, the transmission 120, and the like.

To seal the installation space 131, an oil seal 150 is sleeved on the main shaft 110. The oil seal 150 is located in the mounting hole 141, and the oil seal 150 is rotatably connected to the main shaft 110 about the rotation axis a 1. An oil seal 150 is located between the main shaft 110 and the end cap 140, the oil seal 150 contacts the end cap 140 to form an inner wall of the mounting hole 141 to isolate the main shaft 110 from the end cap 140 and to close the mounting space 131, preventing the lubricant in the mounting space 131 from leaking out of the mounting hole 141. Preferably, in order to ensure the sealing performance of the power output apparatus 100 for construction machinery when used in a dusty environment, the number of the oil seals 150 is two or more, and each oil seal 150 is linearly disposed in the mounting hole 141 along the rotation axis a 1. In view of the manufacturing cost, the number of the oil seals 150 provided in the end cap 140 in this embodiment is most preferably two.

A dust cap 160 is formed on or fixedly mounted to the end of the end cap remote from the housing 130. The dust ring 170 is disposed on the dust cap 160. The dust ring 170 is sleeved on the main shaft to isolate the main shaft 110 from the dust-proof cover 160. The dust cap 160 is provided with a through hole 161. The through hole 161 penetrates the dust-proof cover 160 along the direction of the rotation axis a1 so that the main shaft 110 penetrates and is in rotary connection with the main shaft 110, and one end of the main shaft 110 along the direction of the rotation axis a1 extends out of the through hole 161 and is connected to parts such as a drill rod. Each oil seal 150 is located between the case 130 and the dust-proof cover 160 along the rotation axis a 1. The dust ring 170 is fixedly installed in the through hole 161 of the dust cap 160 to close the installation hole 141. The dust ring 180 is commercially available, for example, a vs.v type sealing ring product manufactured by skofu corporation, and the structure and principle thereof are not described herein.

Thus, dust is prevented from entering the mounting hole 141 when the construction machine is in operation, so that the sealability of each oil seal 150 is ensured. Even if the dust ring 170 is damaged, the possibility of the oil seal 150 contacting dust is reduced because the end of the end cap 140 is blocked by the dust cap 160. So that the construction machine loaded with the construction machine power take-off 100 can be used for a continuous period of time to replace the dust ring 170 after a stoppage. Thereby further ensuring the sealing performance of the oil seal 150.

Specifically, the work machine power output apparatus 100 further includes: a flap 180. Wherein, the shield cover 180 is fixedly installed at one end of the dust-proof cover 160 far from the end cover. The cover 180 is formed with a shaft hole 181 through which the main shaft 110 passes, and the main shaft 110 passes through the shaft hole 181 of the cover 180 to output torque to parts such as a drill rod connected to a construction machine. The dust ring 170 is located between the dust cap 160 and the cap 180 in the direction of the rotation axis a1 to restrict movement of the dust ring 170 in the direction of the rotation axis a1 by the cap 180.

Specifically, the dust-proof cover 160 is provided with, in order along the rotation axis a 1: the connecting portion 162 and the mounting portion 163. Wherein, the connecting portion 162 is disposed at one end of the dust-proof cover 160 near the end cover. The flap 180 is fixedly coupled to the mounting portion 163. The through hole 161 penetrates the connection part 162 and the mounting part 163, and the dust ring 170 is located in a portion of the through hole 161 located in the mounting part 163. The aperture of the through hole 161 at the connection portion 162 is smaller than that at the mounting portion 163. More specifically, the shielding cover 180 is at least partially located within an extension of the through hole 161 at the mounting portion 163 in the direction of the rotation axis a1, that is, the aperture of the shaft hole 181 is smaller than the aperture of the through hole 161 at the mounting portion 163, so that the shielding cover 180 is used to prevent the dust ring 170 from moving out of the through hole 161, thereby achieving axial positioning of the dust ring 170.

In this way, the dust ring 170 contacts with the inner wall of the through hole 161 formed by the mounting part 163 to prevent impurities of the external environment from entering the mounting hole 141, and the axial movement of the dust ring 170 is reduced by the shielding cover 180, so that the dust ring 170 contacts with the inner wall of the through hole 161 formed by the mounting part 163 tightly, and the isolation and sealing effects of the dust ring on the external impurities are ensured.

Specifically, the hole diameter of the shaft hole 181 is larger than the shaft diameter of the spindle 110 passing through the shaft hole 181, so that the spindle 110 and the blocking cover 180 are arranged at intervals, and abrasion caused by contact with the blocking cover 180 when the spindle 110 rotates is avoided. Meanwhile, the hole diameter of the through hole 161 at the connection portion 162 is defined to be larger than the shaft diameter of the main shaft 110 passing through the connection portion 162, that is, the through hole 161 is a stepped hole. The dust ring 170 contacts an end surface formed when the inner diameter of the stepped hole varies to restrict axial movement of the dust ring 170 in the direction of the rotation axis a1 toward an end near the case 130.

Specifically, at least one oil seal 150 contacts an end surface of the connection part 162 near one end of the end cap 140 to restrict the movement of the oil seal 150 in the direction of the rotation axis a1, thereby restricting each oil seal 150 to the same side of the dust-proof cover 160, i.e., forming a protection for the oil seal 150 from external impurities by the dust-proof cover 160.

Specifically, the dust cap 160 and the end cap 140 are provided with at least one oil injection passage 142. An oil injection passage 142 provided on the end cap 140 has one end communicating with the outside of the end cap 140 and the other end communicating with the mounting hole 141. One end of the oil injection passage 142 provided in the dust cap 160 communicates with the outside of the dust cap 160, and the other end communicates with the through hole 161.

Thus, by providing the oil filling passage 142, lubricating oil can be filled into the mounting hole 141 and the through hole 161, so that each oil seal 150 can be easily lubricated, and the possibility of abrasion is reduced. And part of the oiling channel 142 is communicated between the oil seal 150 and the dust ring 170, so that the dust ring 170 can be lubricated, and abrasion of the end face of the dust ring 170 contacting the dust cover 160 and abrasion of the contact surface of the main shaft 110 and the dust ring 170 in the rotation process of the main shaft 110 are reduced.

More specifically, the oil seal 150 is formed with an oil cavity 151, and the oil cavity 151 is provided with an opening at one end in the direction of the rotation axis a1, so that the oil cavity 151 communicates with at least one oil injection passage 142 or with the installation space 131 through the installation hole 141, thereby enabling the lubricating oil entering the installation hole 141 from the oil injection passage 142 to be stored in the oil cavity 151 or the lubricating oil in the installation space 131 to enter the oil cavity 151, and enabling the oil seals to be sufficiently lubricated.

More specifically, the hole diameter of the mounting hole 141 is larger than the hole diameter of the through hole 161 at the connection portion 162 so as to mount the oil seals 150 in the mounting hole 141 and ensure that the mounting hole 141 can be filled with sufficient lubricating oil to sufficiently lubricate each oil seal 150. Meanwhile, the diameter of the through hole 161 and the diameter of the mounting hole 141 are changed to form a labyrinth-shaped lubrication space between the end cover 140 and the dust-proof cover 160, so that external impurities are difficult to enter the mounting hole 141 from the part of the through hole 161 located at the connecting part 162, and the possibility of abrasion of each oil seal 150 in the mounting hole 141 is reduced, so that the sealing performance of the oil seal 150 is ensured.

More specifically, the portion of the through hole 161 communicating with the oil filling passage 142 is located between the oil seal 150 and the dust ring 170. I.e., lubricating oil can be injected between the oil seal 150 and the dust ring 170 to lubricate both simultaneously. The cover 180 restricts the movement of the dust ring 170 in the direction of the rotation axis a1, and prevents the cover 180 from being pushed to move during the injection of the lubricant to ensure the sealing effect of the dust ring 170.

In the solution that the end of the oil injection channel 142 away from the through hole 161 extends along the direction perpendicular or oblique to the rotation axis a1, that is, the end of the oil injection channel 142 away from the mounting hole 141 penetrates the end cover 140 along the direction perpendicular or oblique to the rotation axis a1, so that the end of the oil injection channel 142, which is in communication with the external environment, is not disposed on the end surface of the end cover 140 along the direction of the rotation axis a 1. In this way, the oil filling passage 142 can be conveniently opened to replenish the lubricating oil into the mounting hole 141 without being restricted by the components provided on the main shaft 110 or the end cap 140.

Specifically, the work machine power output apparatus 100 further includes: a grease nipple 190. Wherein the grease fitting 190 is detachably mounted on the dust cap 160. The grease nipple 190 is in one-to-one correspondence with the grease filling channel 142, and the grease nipple 190 is embedded into one end of the grease filling channel 142 corresponding thereto, which is far away from the through hole 161, so as to close the grease filling channel 142. The end of the grease nipple 190, which is inserted into the grease filling channel 142 and is far away from the mounting hole 141, is fixed on the end cover 140 by means of threaded connection or interference fit, and after the grease nipple 190 is removed or opened, grease can be filled into the grease filling channel 142. The grease nipple is commercially available and is a part commonly used in the field for oiling, and the structure of the grease nipple is not improved, so that the structure and the principle of the grease nipple are not repeated here.

In general, the grease may be injected into the installation space 131, but when the grease nipple 190 is used as a switch for switching the grease filling passage 142 to and from the external environment, the grease filling passage is only used to inject grease into the installation space 131, but not used to inject grease due to the limitation of the structure of the grease nipple 190.

More specifically, more openings communicating with the external environment may be additionally provided on the oil filling channel 142, and when the plug 191 is detachably mounted at the openings, the openings are blocked to prevent the grease from leaking from the openings when the plug 191 is fixedly mounted at the openings of the oil filling channel 142. In addition, when the grease is injected, the plug 191 may be removed from the opening of the grease filling passage 142, so that the injection amount of the grease may be observed at the opening.

Alternatively, the end of the oil filling passage 142 remote from the through hole 161 extends in a direction perpendicular or oblique to the rotation axis a 1.

In the related art, one end of the main shaft 110 connected to an external device to output torque is often mounted with components such as a coupling, and at the same time, the end face of the end cap 140 along the direction of the rotation axis a1 is often mounted with components such as a sensor, and if one end of the oil filling channel 142 connected to the external environment is disposed on the end face of the end cap 140 along the direction of the rotation axis a1, the axial dimension of the main shaft 110 may be longer, or the grease nipple 190 and the plug 191 are not easy to operate, which makes it difficult to open the lubrication channel and fill the installation hole 141 with lubricating oil.

The engineering machinery is used for illustrating the inventive concept and the technical scheme. However, it should be understood that the power output apparatus provided in the present application can be applied to equipment such as a construction machine and a mining machine, for example, a rock drill rig, and thus the "construction machine" should not be construed as limiting the technical field to which the present utility model is applied. The foregoing description is only of the preferred embodiments of the present disclosure and description of the principles of the technology being employed. It will be appreciated by those skilled in the art that the scope of the utility model in the embodiments of the present disclosure is not limited to the specific combination of the above technical features, but encompasses other technical features formed by any combination of the above technical features or their equivalents without departing from the spirit of the utility model. Such as the above-described features, are mutually substituted with (but not limited to) the features having similar functions disclosed in the embodiments of the present disclosure.

Claims (10)

1. A power take-off for a work machine, comprising:

the device comprises a main shaft, a transmission piece, a box body and an end cover;

wherein the transmission piece is used for being connected to a power source to rotate around a rotation axis under the drive of the power source; the transmission part is coaxially and fixedly arranged on the main shaft so as to drive the main shaft to rotate when rotating; the box body is provided with an installation space for placing the transmission part and a perforation penetrating through the installation space along the direction of the rotation axis; the end cover is fixedly arranged at one end of the box body along the direction of the rotation axis;

the method is characterized in that:

a mounting hole communicated with the mounting space is formed in the end cover; one end of the main shaft passes through the perforation and the mounting hole along the direction of the rotation axis to form rotation connection with the box body and the end cover around the rotation axis;

the engineering machinery power output device further comprises: a dust-proof cover, a dust-proof ring and a plurality of oil seals;

the dust-proof cover is formed at or fixedly arranged at one end of the end cover far away from the box body; the dust ring is connected to the dust separation cover; the dustproof sleeve is sleeved on the main shaft to isolate the main shaft from the dust-isolating cover;

the dust-proof cover is provided with a through hole; the through hole penetrates through the dust-proof cover along the direction of the rotation axis so as to enable the main shaft to penetrate through and form rotary connection with the main shaft; each oil seal is positioned between the box body and the dust-proof cover along the direction of the rotation axis; the dustproof ring is fixedly arranged in the through hole of the dust separation cover so as to seal the mounting hole.

2. The construction machine power take-off according to claim 1, wherein:

the engineering machinery power output device further comprises: a blocking cover;

wherein, the baffle cover is fixedly arranged at one end of the dust-proof cover far away from the end cover; the baffle cover is provided with a shaft hole for the spindle to pass through; the dust ring is positioned between the dust separation cover and the blocking cover along the direction of the rotation axis so as to limit the movement of the dust ring along the direction of the rotation axis through the blocking cover.

3. The construction machine power take-off according to claim 2, wherein:

the dust-proof cover is sequentially provided with: a connecting part and a mounting part;

wherein the connecting part is arranged at one end of the dust-proof cover close to the end cover; the baffle cover is fixedly connected to the mounting part; the through hole penetrates through the connecting part and the mounting part, and the dust ring is positioned in the part of the through hole positioned in the mounting part; the aperture of the through hole at the connection portion is smaller than the aperture at the mounting portion.

4. A construction machine power take-off according to claim 3, wherein:

the baffle cover is at least partially positioned in the extension range of the through hole at the mounting part along the rotation axis direction so as to prevent the dust ring from moving out of the through hole.

5. The construction machine power take-off according to claim 4, wherein:

the aperture of the shaft hole is larger than the shaft diameter of the spindle passing through the shaft hole part so that the spindle and the baffle cover are arranged at intervals; the aperture of the through hole at the connecting part is larger than the shaft diameter of the spindle passing through the connecting part.

6. A construction machine power take-off according to claim 3, wherein:

at least one of the oil seals is in contact with an end face of the connecting portion near one end of the end cover to restrict movement of the oil seal in the rotation axis direction.

7. The construction machine power take-off according to any one of claims 1 to 6, wherein:

at least one oiling channel is arranged on the dust-proof cover; one end of the oiling channel is communicated with the outside of the dust-proof cover; the other end of the oiling channel is communicated with the through hole.

8. The construction machine power take-off according to claim 7, wherein:

the part of the through hole, which is communicated with the oiling channel, is positioned between the oil seal and the dust ring.

9. The construction machine power take-off according to claim 8, wherein:

the oil injection passage extends in a direction perpendicular to or inclined to the rotation axis at an end away from the through hole.

10. The construction machine power take-off according to claim 7, wherein:

the engineering machinery power output device further comprises: a grease nipple;

wherein, the grease nipple is detachably arranged on the dust-proof cover; the grease nipple is in one-to-one correspondence with the grease injection channels, and the grease nipple is embedded into one end, away from the through hole, of the grease injection channel corresponding to the grease nipple so as to seal the grease injection channels.