CN110744718B

CN110744718B - Agitating lorry

Info

Publication number: CN110744718B
Application number: CN201911088226.0A
Authority: CN
Inventors: 陈威; 马业松; 杨瑞峰; 孙加龙
Original assignee: Wuhu CIMC Ruijiang Automobile Co Ltd
Current assignee: Wuhu CIMC Ruijiang Automobile Co Ltd
Priority date: 2019-11-08
Filing date: 2019-11-08
Publication date: 2024-07-12
Anticipated expiration: 2039-11-08
Also published as: CN110744718A

Abstract

The invention provides a mixer truck, which comprises a frame, a mixing drum, a feeding and discharging device and a rotary sealing assembly, wherein the frame is provided with a plurality of grooves; the rear end part of the stirring cylinder is provided with a material opening; the rotary sealing assembly comprises a fixed ring, a rotary ring and a sealing body; the fixed ring is fixedly connected with the feeding and discharging device; the fixing ring is internally provided with an axially extending mounting groove and at least one air inlet channel; the rotating ring is connected to the material opening of the stirring cylinder and can rotate along with the stirring cylinder; the rotating ring stretches into the fixed ring and is rotatably connected with the fixed ring; an air pressure chamber and a sealing cavity are formed between the rotating ring and the fixed ring; the air pressure chamber is communicated with the air inlet channel; the sealing body is annular and is accommodated in the sealing cavity in a sealing manner; a groove is formed in the end face of one end of the sealing body in a surrounding manner; the inner peripheral wall of the groove is inclined toward the center of the sealing body in a direction toward the opening of the groove. The invention can effectively improve the sealing performance of the material opening of the stirring cylinder in a mode of adding the sealing body into the air pressure chamber.

Description

Agitating lorry

Technical Field

The invention relates to the field of transport vehicles, in particular to a stirring vehicle.

Background

The Chinese patent CN205325993U discloses a stirring transport vehicle, which comprises a rolling type stirring cylinder, wherein the stirring cylinder comprises a cylinder body for accommodating materials and a discharge port arranged at one end of the cylinder body, and a material output control device is further arranged at the discharge port; a sealing component is arranged between the discharge hole and the material output control device; the sealing component comprises a flange, a slewing bearing, a supporting beam and a connecting plate; the flange is fixedly assembled on the discharge hole and can rotate along with the rotation of the cylinder body; the slewing bearing comprises a fixed element and a rotating element matched with the fixed element; the rotating element is fixedly arranged in the flange and keeps synchronous rotation with the flange, and the fixing element is matched with the rotating element and is positioned outside the flange. Through setting up seal assembly between discharge gate and material output controlling means, flange, rotating element, sealing washer and the flange gasket in the seal assembly rotate along with the barrel together, and fixed element, connecting plate, supporting beam remain fixed to keep material output controlling means fixed, and seal through sealing washer and flange gasket, thereby guarantee that concrete can not follow the discharge gate and flow. And a sealing cavity for accommodating lubricating oil is formed among the flange gasket, the sealing gasket, the slewing bearing and the connecting plate.

In this stirring transport vechicle, adopt sealing gasket and lubricating oil's sealing means in order to prevent the leakage of concrete in the discharge gate department of churn, this kind of sealing means is traditional mechanical seal and refuels fat seal, and the wearing and tearing is faster, and sealing reliability is poor, need frequently to pour into lubricating oil in order to supplement the lubricating oil of loss into sealed chamber and just can guarantee sealed effect.

Disclosure of Invention

The invention aims to provide a mixer truck, which improves the sealing performance of a discharge hole of a mixing drum.

In order to solve the technical problems, the invention adopts the following technical scheme: the agitating lorry comprises a frame, an agitating drum rotatably arranged on the frame, a feeding and discharging device fixed on the frame, and a rotary sealing assembly connected between the agitating drum and the feeding and discharging device; the rear end part of the stirring cylinder is provided with a material opening; the rotary sealing assembly comprises a fixed ring, a rotary ring and a sealing body; the fixed ring is fixedly connected with the feeding and discharging device; an axially extending mounting groove is formed in the inner part of the air inlet pipe, and at least one air inlet channel communicated with the mounting groove from the periphery of the air inlet pipe is formed in the air inlet pipe; the rotating ring is connected to the material opening of the stirring cylinder and can rotate along with the stirring cylinder; the fixing ring is inserted into the mounting groove of the fixing ring and is rotatably connected with the fixing ring; an air pressure chamber and a sealing cavity are formed between the rotating ring and the fixed ring; the air pressure chamber is communicated with the air inlet channel; the air pressure chamber and the sealing cavity encircle the axis of the material port; the sealing body is annular and is accommodated in the sealing cavity in a sealing manner; a groove is formed in an end face of one end of the sealing body in a ring manner; the inner peripheral wall of the groove is inclined toward the center of the sealing body in a direction toward the opening of the groove.

Optionally, the fixing ring comprises a containing part and a first sealing part which are connected front and back; the mounting groove is formed from the front end of the accommodating part to the first sealing part, and a step is formed at the joint of the accommodating part and the first sealing part; the first sealing part is connected with the feeding and discharging device; the rotating ring comprises a rotating part and a second sealing part which extends backwards from the rear end surface of the rotating part; the rotary part is connected with the stirring cylinder and is rotatably connected with the accommodating part; the air pressure chamber and the sealing cavity are formed between the second sealing part and the first sealing part; and a shaft shoulder is formed at the rear end face of the rotating part and is abutted with the step of the mounting groove.

Optionally, the first sealing part comprises a peripheral wall arranged in the circumferential direction and an end wall arranged at the rear end of the peripheral wall in the vertical direction, and the front end of the peripheral wall is connected with the accommodating part; a mounting groove for accommodating the first sealing part is formed between the peripheral wall and the end wall; the air inlet channel is formed in the peripheral wall; the air pressure chamber is formed between an outer peripheral surface of the first seal portion and the outer peripheral wall.

Optionally, a ring groove is formed in the rear end face of the second sealing part; the first sealing part is shielded at the periphery of the annular groove, and the sealing cavity is formed between the first sealing part and the annular groove.

Optionally, a space is formed between the annular groove and the inner peripheral surface and the outer peripheral surface of the second sealing part; the end wall shields the opening of the annular groove to form the sealing cavity; the opening of the groove of the sealing body faces the end wall.

Optionally, the annular groove penetrates an inner circumferential surface of the second sealing portion; the first sealing part further comprises an inner peripheral wall vertically connected with the end wall, and the inner peripheral wall and the end wall jointly shield the annular groove to form the sealing cavity; the opening of the groove of the sealing body faces the bottom surface of the ring groove.

Optionally, the sealing cavity is formed between the outer peripheral surface of the second sealing part and the outer peripheral wall, and between the second sealing part and the end wall, and is adjacent to the air pressure chamber, and in the sealing cavity, an opening of the groove of the sealing body faces the end wall.

Optionally, the rotary sealing assembly further comprises a spacer bush, the spacer bush is hermetically sleeved between the periphery of the second sealing part and the peripheral wall, and the air pressure chamber is formed inside the spacer bush; the spacer bush is also in axial abutting connection with the sealing body sleeved on the periphery of the second sealing part.

Optionally, the rotary sealing assembly further comprises a sealing ring, and the sealing ring is sleeved on the periphery of the second sealing part and is attached to the shaft shoulder.

Optionally, the sealing body is made of nitrile rubber material, polyurethane rubber material or fluororubber material.

Optionally, the fixed ring is detachably connected with the feeding and discharging device, the fixed ring is detachably connected with the rotating ring, and the rotating ring is detachably connected with the stirring barrel.

Optionally, the rotating ring is connected with the stirring barrel through a flexible deformable connecting piece, one end of the connecting piece is annularly arranged at the material opening and detachably connected with the stirring barrel, and the other end of the connecting piece is detachably connected with the front end face of the rotating ring.

According to the technical scheme, the invention has at least the following advantages and positive effects: in the mixer truck, the material opening of the mixing drum is connected with the material inlet and outlet device through the rotary sealing assembly, and the fixed ring and the rotary ring of the rotary sealing assembly form reliable sealing in a mode of adding a sealing body into the air pressure chamber. The end face of the sealing body is provided with a groove, the inner peripheral wall of the groove is inclined, and when materials in the stirring barrel permeate outwards from the rotating ring, the structure of the groove can facilitate the materials to enter the groove preferentially, so that the materials are prevented from permeating into a gap between the rotating ring and the fixed ring; and the material enters the groove and then generates extrusion force on the sealing body, so that the bonding degree of the sealing body and the sealing cavity is enhanced, and a better sealing effect is achieved. In addition, the air pressure chamber can prevent water from penetrating from the gap between the rotating ring and the fixed ring under the action of air pressure. In a comprehensive view, the sealing performance of the material opening of the stirring cylinder can be effectively improved through the mode that the air pressure chamber is added with the sealing body.

Drawings

FIG. 1 is a schematic illustration of the connection of a mixing drum to a feed and discharge device in an embodiment of the mixer truck of the present invention.

Fig. 2 is a partial enlarged view at a in fig. 1.

FIG. 3 is a schematic cross-sectional view of the rotary seal assembly of FIG. 2.

Fig. 4 is a partial enlarged view at B in fig. 3.

Fig. 5 is a schematic cross-sectional view of the mating of the stationary ring and the rotating ring of the rotary seal assembly of fig. 3.

FIG. 6 is an exploded schematic view of a transition unit of the rotary seal assembly of FIG. 3.

Fig. 7-10 are schematic cross-sectional views of several other variations of the rotary seal assembly of the truck of fig. 1, respectively.

The reference numerals are explained as follows:

1. a stirring cylinder; 11. a material port;

2. A feeding and discharging device;

3. A rotary seal assembly; 301. an air pressure chamber; 302. an inner sealed cavity; 303. an outer sealed cavity; 305. a mounting hole; 307. a receiving chamber; 308. a receiving area;

31. A fixing ring; 311. a housing part; 312. a first sealing part; 3121. an outer peripheral wall; 3122. an end wall; 3123. an inner peripheral wall; 316. an air intake passage; 3101. a step;

32. a rotating ring; 321. a turning part; 3211. a shaft shoulder; 3213. a protrusion; 322. a second sealing part; 3221. a ring groove; 324. a through hole;

33. A transition unit; 331. a fixed bracket; 3311. slotting; 332. a roller block;

34. a baffle;

35. a sealing body; 351. a groove;

36. A seal ring;

37. a spacer bush;

38. An intake valve;

4. a connecting piece;

5. a fastener.

Detailed Description

Exemplary embodiments that embody features and advantages of the present invention will be described in detail in the following description. It will be understood that the invention is capable of various modifications in various embodiments, all without departing from the scope of the invention, and that the description and illustrations herein are intended to be by way of illustration only and not to be construed as limiting the invention.

The invention provides a mixer truck, which can be used for mixing and transporting concrete. The mixer truck generally comprises a frame, a mixing drum rotatably mounted on the frame, a feeding and discharging device fixed on the frame, and a rotary sealing assembly connected between the mixing drum and the feeding and discharging device. The stirring cylinder stirs the concrete material in the stirring cylinder through the rotation relative to the frame, the feeding and discharging device inputs raw materials into the stirring cylinder and outwards outputs the stirred concrete in the stirring cylinder, and the rotary sealing assembly is in rotary connection and sealing with the feeding and discharging device.

The embodiment of the invention is mainly optimized for the rotary sealing assembly and the related connection mode thereof, the related structures of the frame, the stirring cylinder and the feeding and discharging device can refer to the related technologies, and the rotatable mounting of the stirring cylinder relative to the frame and the mounting structure of the feeding and discharging device and the frame can refer to the related technologies as well.

Referring to fig. 1, in the mixer truck of the present embodiment, a material port 11 is provided at a rear end of a mixing drum 1, and a rotary seal assembly 3 is connected between the material port 11 of the mixing drum 1 and a material inlet and outlet device 2.

Referring to fig. 2, the mixing drum 1 and the rotary seal assembly 3 are also preferably connected by a flexibly deformable connecting member 4. The front end of the connecting piece 4 is arranged at the material opening 11 of the mixing drum 1 and is detachably connected with the mixing drum 1 through the fastening piece 5. The rear end of the connector 4 is detachably connected to the rotary seal assembly 3 by a fastener 5. The cross section at the middle part of the connecting piece 4 is provided with a curve section and can be flexibly deformed, so that the stirring cylinder 1 and the rotary sealing assembly 3 form flexible connection, displacement change during load change of the stirring cylinder 1 can be compensated, rotary connection and sealing of the rotary sealing assembly 3 are not influenced by displacement of the stirring cylinder 1, and sealing performance and rotary precision of the rotary sealing assembly 3 are ensured. The fastener 5 may be a bolt, a fixed pin, or the like.

Referring to fig. 2 and 3, the rotary seal assembly 3 mainly includes a stationary ring 31, a rotating ring 32 rotatably coupled to the stationary ring 31, and a sealing body 35 sealingly received between the stationary ring 31 and the rotating ring 32. Wherein the stationary ring 31 and the rotating ring 32 are rotatably connected by a transition unit 33. In this embodiment, the rotary seal assembly 3 further comprises a seal ring 36.

Referring to fig. 3 and 5, the retainer ring 31 has a generally annular structure, and an outer circumferential surface thereof is a cylindrical surface, in which an axially extending mounting groove is provided, which is stepped so that the inner circumference of the retainer ring 31 is formed with a step 3101. The mounting groove is used for accommodating the rotating ring 32, and forms separated functional partitions inside the fixed ring 31 through a step-shaped structure thereof so as to respectively realize the functions of rotating connection and sealing.

The fixing ring 31 is integrally formed, and the fixing ring 31 is axially divided into a receiving portion 311 and a first sealing portion 312, which are connected in front-back direction, according to the functional partition of the fixing ring 31 for easy understanding. The housing portion 311 and the first sealing portion 312 are demarcated by a step 3101 of a mounting groove that opens from the front end of the housing portion 311 toward the first sealing portion 312, a portion of the mounting groove located in the housing portion 311 constitutes a mounting region, a portion located in the first sealing portion 312 constitutes a sealing region, a caliber of the mounting region is larger than that of the sealing region, the step 3101 of the mounting groove is located at a junction between the housing portion 311 and the first sealing portion 312, and the mounting groove does not penetrate the rear end surface of the first sealing portion 312.

The accommodating portion 311 is rotatably connected to the rotating ring 32, and the accommodating portion 311 has a cylindrical structure, and a space enclosed inside thereof constitutes an installation area of the installation groove. The front end surface of the housing portion 311 has a plurality of mounting holes 305 distributed in the circumferential direction.

The first sealing portion 312 includes an outer peripheral wall 3121 disposed circumferentially and an end wall 3122 disposed perpendicularly to the rear end of the outer peripheral wall 3121, and an inner peripheral wall 3123 connected perpendicularly to the end wall 3122 is also preferably provided in the present embodiment. The space enclosed between the outer circumferential wall 3121, the end wall 3122, and the inner circumferential wall 3123 constitutes a sealing area of the installation groove.

The outer peripheral wall 3121 has a cylindrical structure, and the front end thereof contacts the accommodating portion 311, and the thickness of the outer peripheral wall 3121 is greater than the thickness of the accommodating portion 311, thereby forming the step 3101 of the installation groove. The end wall 3122 is generally circular with an inner bore opposite the port 11 of the mixing drum 1 for material ingress and egress. The inner circumferential wall 3123 is cylindrical, extending forward from the inner end of the end wall 3122, and the axial length of the inner circumferential wall 3123 is smaller than the axial length of the outer circumferential wall 3121.

At least one air intake passage 316 is opened in the peripheral wall 3121 along the circumferential direction thereof, and the air intake passage 316 communicates from the outer peripheral surface of the peripheral wall 3121 to an installation groove therein. The air inlet channel 316 may preferably extend directly in the radial direction of the outer peripheral wall 3121 with a shorter path, but is not limited thereto. The outer end of the intake passage 316 may be controlled by mounting an intake valve 38.

The rear end surface of the outer peripheral wall 3121 is provided with an installation hole 305, which can be detachably connected and fixed with the feeding and discharging device 2 by a fastener 5.

Referring to fig. 2 to 5, a rotating ring 32 is connected to the stirring cylinder 1 at the material inlet 11, and can rotate with the stirring cylinder 1. The rotating ring 32 extends into the mounting groove of the fixed ring 31 and is rotatably connected with the fixed ring 31. The middle part of the rotating ring 32 is provided with a through hole 324 which is penetrated from front to back, and the through hole 324 is opposite to the material inlet 11 of the stirring cylinder 1 for material to enter and exit. The axis of the rotating ring 32 substantially coincides with the axis of the spout 11.

The rotating ring 32 is also integrally constructed, and the rotating ring 32 may be divided into a swivel portion 321 and a second sealing portion 322 protruding rearward from the rear end surface of the swivel portion 321 according to functions at different portions thereof when it is fitted with the fixing ring 31. The shapes of the turning part 321 and the second sealing part 322 are cylindrical, the diameter of the turning part 321 is larger than that of the second sealing part 322, the joint of the turning part 321 and the second sealing part 322 forms a step shape, and a shaft shoulder 3211 is formed at the rear end surface of the turning part 321.

The front end surface of the turning portion 321 is provided with a plurality of mounting holes 305 distributed circumferentially to be detachably connected and fixed with the connecting member 4 by the fastener 5, thereby being connected with the stirring cylinder 1.

The turning portion 321 is accommodated in the accommodating portion 311 of the retainer ring 31, that is, an installation region of the installation groove. The shoulder 3211 of the turning part 321 abuts against the step 3101 of the mounting groove, and the axial limit of the rear end is formed. A circumferential accommodation chamber 307 is formed between the outer peripheral surface of the turning portion 321 and the inner peripheral surface of the accommodation portion 311, and a front end of the accommodation chamber 307 is opened. The receiving cavity 307 is used for receiving the transition unit 33 such that the rotating ring 32 can rotate relative to the stationary ring 31 by means of the transition unit 33.

In this embodiment, the rear end of the turning portion 321 further has a protrusion 3213 protruding from the outer periphery thereof, and a circumferential gap is formed between the protrusion 3213 and the inner peripheral surface of the accommodating portion 311 to form an annular accommodating region 308. The rear end surface of the protrusion 3213 also abuts against the step 3101 of the installation groove.

The second sealing portion 322 is accommodated in the first sealing portion 312 of the retainer ring 31, i.e., a sealing region of the mounting groove. The outer peripheral surface of the second seal portion 322 is spaced apart from the outer peripheral wall 3121 of the first seal portion 312, and the rear end surface of the second seal portion 322 is opposed to the end wall 3122 of the first seal portion 312.

The outer peripheral surface of the second seal portion 322, the rear end surface of the turning portion 321, and the outer peripheral wall 3121 and the end wall 3122 of the first seal portion 312 are surrounded to form an annular chamber around the axis of the turning ring 32. In the axial direction, the middle part of the annular cavity forms an air pressure chamber 301, the air pressure chamber 301 is communicated with an air inlet channel 316, and the air pressure chamber 301 can prevent the permeation of water quality through the air pressure action in the air pressure chamber. The rear portion adjacent to the air pressure chamber 301 forms a seal chamber for accommodating the seal body 35, which is located at the outer periphery of the second seal portion 322, which will be referred to as an outer seal chamber 303. The front portion adjacent to the air pressure chamber 301 is adapted to receive the sealing ring 36.

A rear end surface of the second sealing portion 322 is provided with an annular groove 3221, the annular groove 3221 penetrates through an inner circumferential surface of the second sealing portion 322, an inner opening of the annular groove 3221 is blocked by an inner circumferential wall 3123 of the first sealing portion 312, and a rear end opening of the annular groove 3221 is blocked by an end wall 3122 of the first sealing portion 312. A seal chamber for accommodating the seal body 35 is formed between the second seal portion 322 and the first seal portion 312, i.e., at the ring groove 3221, and is located at the inner periphery of the second seal portion 322, which is referred to as the inner seal chamber 302.

Referring to fig. 3 and 4, the sealing body 35 is ring-shaped, and has a groove 351 formed on one end surface thereof, and an inner peripheral wall of the groove 351 is inclined toward the center of the sealing body 35 in a direction opening to the groove 351. The cross section of the groove 351 is a right trapezoid, the inclined waist of the right trapezoid corresponds to the inner side peripheral wall of the groove 351, and the lower bottom edge of the right trapezoid corresponds to the opening of the groove 351.

The sealing body 35 may be made of nitrile rubber, polyurethane rubber or fluororubber. The nitrile rubber has the advantages of excellent oil resistance, higher wear resistance, better heat resistance, strong adhesive force, good water resistance, air tightness and excellent adhesive property. The polyurethane rubber (polyurethane rubber) has the advantages of high hardness, good strength, high elasticity, high wear resistance, tear resistance, aging resistance, ozone resistance, radiation resistance, good conductivity and the like. Fluororubbers have excellent heat resistance, oxidation resistance, oil resistance, corrosion resistance and atmospheric aging resistance. The excellent performance of the sealing body 35 by utilizing the materials can be matched with the application working condition of the mixer truck, so that the sealing body can meet the sealing performance, and meanwhile, the sealing body has a longer service life and higher use reliability.

Referring to fig. 2 to 5, in this embodiment, a sealing body 35 is sealingly received in the inner sealing cavity 302, the opening of the groove 351 of the sealing body 35 faces the bottom surface of the ring groove 3221, and the sealing body 35 in the inner sealing cavity 302 forms a first seal. The outer seal chamber 303 sealingly receives a seal 35 with the groove 351 of the seal 35 opening toward the end wall 3122, the seal 35 in the outer seal chamber 303 forming a second seal.

The mechanism of action of the seal 35 is: the concrete in the mixing drum 1 is discharged from the port 11 and then sequentially discharged to the feeding and discharging device 2 along the through hole 324 of the rotating ring 32 and the inner hole of the end wall 3122 of the fixed ring 31, and the position where the concrete easily leaks is the rear end of the second sealing portion 322 of the rotating ring 32. When concrete leaks along the rear end of the second sealing portion 322, there are two cases as follows: 1. when the concrete permeates into the gap between the sealing body 35 and the ring groove 3221, the concrete can play a role of adhesion and blocking after solidification, thereby being beneficial to preventing the concrete from further permeating into the gap between the rotating ring 32 and the fixed ring 31; 2. when the concrete is inserted into the groove 351 of the sealing body 35, the structure of the sealing body 35 at the outer peripheral side portion of the groove 351 is turned over in the direction indicated by the arrow marked inside the groove 351 in fig. 4 due to the extrusion of the concrete, and the degree of adhesion of the sealing body 35 to the sealing cavity can be enhanced, thereby improving the sealing effect.

The opening of the groove 351 of the sealing body 35 in the inner sealing cavity 302 and the opening of the groove 351 of the sealing body 35 in the outer sealing cavity 303 are both in the material feeding direction of material leakage, and the material preferably enters the groove 351 of the sealing body 35 during material leakage, so that further leakage is prevented. The inclined structure of the inner peripheral wall of the groove 351 can guide leaked materials, so that the materials can enter the groove 351 more conveniently.

Referring to fig. 3, the seal ring 36 is also annular, has a square cross section, is sealingly sleeved on the outer periphery of the second seal portion 322, and is attached to the shoulder 3211. The sealing ring 36 further isolates the mounting region from the sealing region, so that a better effect is exerted between the rotary connection and the seal, respectively. At the same time, the sealing ring 36 also acts as a third seal, further preventing leaking material from entering the mounting area and affecting the relative rotation between the rotating ring 32 and the stationary ring 31.

The seal ring 36 may employ a slinger, such as grease applied to the mounting area to reduce rotational resistance, and the seal ring 36 may prevent grease from entering the seal area. The sealing ring 36 can also be made of asbestos packing materials to realize sealing effect.

Referring to fig. 6, the transition unit 33 includes a fixed bracket 331 and a plurality of roller blocks 332. Wherein, the fixing bracket 331 is ring-shaped. The fixed bracket 331 is provided with a plurality of slots 3311 at intervals along the circumferential direction thereof to form a tooth-like structure at the circumference of the fixed bracket 331. The slot 3311 extends along the axial direction of the fixing bracket 331.

Referring also to fig. 3, the transition unit 33 is installed between the rotating ring 32 and the fixed ring 31. Wherein, the fixed bracket 331 is disposed in the accommodation area 308 formed between the protrusion 3213 of the rotating ring 32 and the inner wall of the accommodation portion 311 of the fixed ring 31. The plurality of roller blocks 332 are correspondingly clamped in the grooves 3311 of the fixed bracket 331, so that the surfaces of the roller blocks 332 are contacted with the inner wall of the accommodating cavity 307, namely, the outer peripheral surface of the rotating part 321 of the rotating ring 32 and the inner wall of the accommodating part 311 of the fixed ring 31, so as to realize the relative rotation of the rotating ring 32 and the fixed ring 31. The cross section of the roller block 332 is preferably polygonal, so that the roller block is in surface contact with both the rotating portion 321 and the accommodating portion 311, so as to improve the stability of the rotational connection. The roller block 332 is made of a self-lubricating wear resistant material. The self-lubricating wear-resistant material can be polytetrafluoroethylene, polycarbonate or nylon, etc. In addition, the roller block 332 may be made of a highly wear-resistant metal material, such as copper.

The front side of the transition unit 33 is stopped by a baffle 34. The baffle 34 is fixed to the mounting hole 305 on the front end surface of the retainer 31 by the fastener 5, and the baffle 34 is partially stopped at the opening of the housing 307 to prevent the roller block 332 from coming out. The baffle 34 cooperates with the bulge 3213 of the turning part 321 to form axial limit on the roller moving block 332, so that the separation of the rotating ring 32 and the fixed ring 31 during relative rotation is avoided, and the stability of the relative rotation of the fixed ring 31 and the rotating ring 32 is ensured.

In this embodiment, the fixed ring 31 of the rotary seal assembly 3 is detachably connected with the feeding and discharging device 2 through the fastener 5, and the rotating ring 32 is detachably connected with the connecting piece 4, which is equivalent to that the rotating ring 32 is detachably connected with the mixing drum 1, and in addition, the baffle 34 is detachably connected with the fixed ring 31. If any one of the components of the rotary seal assembly 3 is worn or damaged, the rotary seal assembly can be adaptively disassembled and then correspondingly maintained and replaced, and compared with the integral replacement of the rotary seal assembly 3, the structure of the embodiment can greatly reduce maintenance and update costs.

Based on the above description, in the mixer truck of the present embodiment, the rotary connection and rotary sealing between the mixing drum 1 and the feeding and discharging device 2 are realized through the rotary sealing assembly 3, and the reliable sealing is formed by using the air pressure chamber 301 and the sealing body 35, and particularly, a better sealing effect is formed through the structural form of the sealing body 35.

There are many different embodiments of the seal related structures in the rotary seal assembly 3 based on this concept. Fig. 7 to 10 schematically show the structures of four variants, respectively, and the following description will mainly be made of the variants of several variants.

First modification: as shown in fig. 7, this modified structure adds a spacer 37 to the structure of fig. 3. The spacer 37 is sealingly disposed in the annular cavity between the outer periphery of the second sealing portion 322 and the outer peripheral wall 3121 of the first sealing portion 312, the spacer 37 has an inner annular groove 3221, an outer annular groove 3221, and a vent hole radially communicating the inner annular groove 3221 and the outer annular groove 3221, the outer annular groove 3221 is communicated with the air inlet channel 316 on the fixing ring 31, and the air pressure chamber 301 is formed inside the spacer 37. The spacer 37 is abutted against the sealing body 35 and the sealing ring 36 in the annular cavity in the axial direction, so that the sealing body 35 and the sealing ring 36 can be limited in the axial direction.

The second variant: as shown in fig. 8, the main difference between the structure of this modification and the structure shown in fig. 3 is the position where the ring groove 3221 of the second seal portion 322 is provided. With this structure, the annular groove 3221 is spaced from both the outer peripheral surface and the inner peripheral surface of the second seal portion 322, that is, the annular groove 3221 has only a rear end opening. In response to this change, the first sealing portion 312 of the retainer ring 31 no longer has the inner peripheral wall 3123, and only the end wall 3122 is shielded outside the annular groove 3221 to form the inner sealing chamber 302. At this time, the groove 351 of the sealing body 35 accommodated in the inner seal chamber 302 opens to face the end wall 3122. In this modification, the inner peripheral wall 3123 structure of the retainer ring 31 is omitted, and the thickness of the retainer ring 31 can be reduced, thereby reducing the dead weight.

Third modification: as shown in fig. 9, the structure of this modification is compared with fig. 8, in which the ring groove 3221 on the second seal portion 322 is omitted, and accordingly, one seal body 35 is reduced. The sealing body 35 is provided only in the outer seal chamber 303 adjacent to the air pressure chamber 301. In this manner, the thickness of the turn ring 32 can be reduced, and the thickness of the retainer ring 31 can be further reduced, thereby reducing the dead weight to a greater extent, than in the structure shown in fig. 8.

Fourth modification: as shown in fig. 10, in the structure of this modification, a spacer 37 is added, and a pneumatic chamber 301 is formed inside the spacer 37, as compared with fig. 9. The structure and arrangement of the spacer 37 may be the same as those shown in fig. 3, and will not be described in detail.

It will be appreciated that the actual arrangement is not limited to the several illustrated. In some embodiments, the outer seal cavity 303 and the seal 35 therein may be omitted, while the inner seal cavity 302 and the seal 35 therein remain; for another example, a spacer 37 may be added to the modification described in fig. 8, and the air pressure chamber 301 may be formed inside the spacer 37. Other ways of specifically deforming are not listed.

While the invention has been described with reference to several exemplary embodiments, it is to be understood that the terminology used is intended to be in the nature of words of description and of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. The agitating lorry comprises a frame, an agitating drum rotatably arranged on the frame, a feeding and discharging device fixed on the frame, and a rotary sealing assembly connected between the agitating drum and the feeding and discharging device; the rear end part of the stirring cylinder is provided with a material opening; characterized in that the rotary seal assembly comprises:

the fixed ring is fixedly connected with the feeding and discharging device; an axially extending mounting groove is formed in the inner part of the air inlet pipe, and at least one air inlet channel communicated with the mounting groove from the periphery of the air inlet pipe is formed in the air inlet pipe;

the rotating ring is connected to the material opening of the stirring cylinder and can rotate along with the stirring cylinder; the fixing ring is inserted into the mounting groove of the fixing ring and is rotatably connected with the fixing ring; an air pressure chamber and a sealing cavity are formed between the rotating ring and the fixed ring; the air pressure chamber is communicated with the air inlet channel; the air pressure chamber and the sealing cavity encircle the axis of the material port;

A sealing body which is annular and is accommodated in the sealing cavity in a sealing manner; a groove is formed in an end face of one end of the sealing body in a ring manner; the inner peripheral wall of the groove is inclined towards the center of the sealing body in the direction of opening to the groove;

the fixing ring comprises a containing part and a first sealing part which are connected front and back; the mounting groove is formed from the front end of the accommodating part to the first sealing part, and a step is formed at the joint of the accommodating part and the first sealing part; the first sealing part is connected with the feeding and discharging device;

The rotating ring comprises a rotating part and a second sealing part which extends backwards from the rear end surface of the rotating part; the rotary part is connected with the stirring cylinder and is rotatably connected with the accommodating part; the air pressure chamber and the sealing cavity are formed between the second sealing part and the first sealing part; a shaft shoulder is formed at the rear end face of the rotary part and is abutted with the step of the mounting groove;

the first sealing part comprises a peripheral wall arranged in the circumferential direction and an end wall vertically arranged at the rear end of the peripheral wall, and the front end of the peripheral wall is connected with the accommodating part; a mounting groove for accommodating the first sealing part is formed between the peripheral wall and the end wall; the air inlet channel is formed in the peripheral wall; the air pressure chamber is formed between the outer peripheral surface of the first sealing portion and the outer peripheral wall;

the rear end face of the second sealing part is provided with a ring groove; the first sealing part is shielded at the periphery of the annular groove, and the sealing cavity is formed between the first sealing part and the annular groove.

2. The mixer truck according to claim 1, wherein a space is provided between the annular groove and each of the inner peripheral surface and the outer peripheral surface of the second seal portion; the end wall shields the opening of the annular groove to form the sealing cavity; the opening of the groove of the sealing body faces the end wall.

3. The mixer truck according to claim 1, wherein the ring groove penetrates an inner peripheral surface of the second seal portion;

The first sealing part further comprises an inner peripheral wall vertically connected with the end wall, and the inner peripheral wall and the end wall jointly shield the annular groove to form the sealing cavity; the opening of the groove of the sealing body faces the bottom surface of the ring groove.

4. A mixer vehicle according to any one of claims 1-3, characterized in that the outer peripheral surface of the second sealing part forms the sealing chamber with the peripheral wall, the end wall, the sealing chamber being adjacent to the air pressure chamber, in which sealing chamber the opening of the groove of the sealing body faces the end wall.

5. The mixer truck of claim 4 wherein said rotary seal assembly further comprises a spacer sealingly disposed between an outer periphery of said second seal portion and said outer peripheral wall, said spacer defining said pneumatic chamber therein; the spacer bush is also in axial abutting connection with the sealing body sleeved on the periphery of the second sealing part.

6. The mixer truck of claim 1, wherein the rotary seal assembly further comprises a seal ring sleeved on the outer periphery of the second seal portion and attached to the shaft shoulder.

7. The mixer truck of claim 1, wherein the sealing body is made of nitrile rubber, polyurethane rubber or fluororubber.

8. The mixer truck according to claim 1, wherein detachable connection is adopted between the fixed ring and the feeding and discharging device, between the fixed ring and the rotating ring, and between the rotating ring and the mixing drum.

9. The mixer truck of claim 8 wherein said rotatable collar is connected to said mixer drum by a flexible deformable connector, one end of said connector being disposed around said port and detachably connected to said mixer drum, and the other end of said connector being detachably connected to the front face of said rotatable collar.