CN115196556A

CN115196556A - Walking speed reducer of electrically-driven forklift and application method thereof

Info

Publication number: CN115196556A
Application number: CN202211082824.9A
Authority: CN
Inventors: 郝鸣; 张治峰; 吕刚; 袁浩; 兰青
Original assignee: Jiangsu Guomao Reducer Group Co ltd
Current assignee: Jiangsu Guomao Reducer Group Co ltd
Priority date: 2022-09-06
Filing date: 2022-09-06
Publication date: 2022-10-18
Anticipated expiration: 2042-09-06
Also published as: CN115196556B

Abstract

The invention relates to the technical field of speed reducers, in particular to an electric forklift walking speed reducer and a using method thereof; the speed reducer includes: the brake seat is provided with a brake cavity, a first oil duct, a second oil duct and a first step surface; the connecting sleeve is provided with a spline tooth part; the friction plate set comprises a static friction plate and a dynamic friction plate; the first piston sleeve is provided with a second step surface, a third step surface, a fourth step surface and a third oil channel, and a first oil cavity is formed between the first step surface and the second step surface at intervals; the stop block is arranged in the brake cavity; the two ends of the first spring are respectively connected with the first piston sleeve and the stop block; the second piston sleeve is provided with a fifth step surface, and a second oil cavity is formed by the fourth step surface and the fifth step surface at intervals; the transmission sleeve rotates on the brake seat; the transmission shaft rotates in the transmission sleeve; the planetary reduction gear set is used for the transmission connection of the transmission sleeve and the transmission shaft; the motor and the transmission shaft are connected with the connecting sleeve key. This electric fork truck walking speed reducer can effectively promote brake sensitivity.

Description

Walking speed reducer of electrically-driven forklift and application method thereof

Technical Field

The invention relates to the technical field of speed reducers, in particular to an electric forklift walking speed reducer and a using method thereof.

Background

The electric forklift is a forklift driven by a storage battery as source power, and drives a motor and an oil pressure system to work through electric power, so that the walking and loading and unloading functions are realized, the electric forklift is controlled more conveniently and flexibly, and is free of tail gas emission and more environment-friendly, so that the electric forklift gradually replaces an internal combustion forklift.

The electric forklift runs by driving the forklift hub through the motor, and the motor is high in rotating speed and small in torque, so that a speed reducer is required to be used for connecting the motor and the hub; meanwhile, due to the special use environment of the forklift, the forklift needs to be capable of accurately controlling advancing and braking when carrying goods, and therefore a brake can be arranged in the speed reducer for braking.

The prior art brake usually adopts a friction plate group control mode, wherein the friction plate group is provided with dynamic friction plates and static friction plates which are arranged in a staggered mode, and the brake is realized by friction force generated by the adhesion of the dynamic friction plates and the static friction plates by extruding the friction plate group. In the related art, the pressing and releasing of the friction plate set are usually achieved by using hydraulic oil to push a single piston. In order to ensure the safety during parking, the piston is required to be pressed against the friction plate set to keep the brake when oil is not supplied, and correspondingly, the piston is pushed away from the friction plate set when the vehicle is required to move. It can be seen that the brake structure is affected by the pressure relief time of the hydraulic oil, which results in longer response time of the brake, and as the service time increases, the return sensitivity of the spring also becomes worse, which also results in increased response time of the brake.

Therefore, there is a need for an electrically driven forklift running speed reducer with higher braking sensitivity.

Disclosure of Invention

The invention provides an electric forklift walking speed reducer which can effectively solve the problems in the background technology. The invention also provides a use method of the electric forklift walking speed reducer, and the same technical effects can be achieved.

The invention provides an electrically-driven forklift walking speed reducer, which comprises:

the brake seat is arranged on the forklift body, a brake cavity penetrating through two ends is arranged in the brake seat, and a first oil duct and a second oil duct which are communicated with the outer side and the brake cavity are arranged in the brake seat; a first step surface is arranged in the brake seat;

the connecting sleeve is arranged in the brake cavity, and a spline tooth part is arranged on the circumferential outer side of the connecting sleeve;

the friction plate set comprises a plurality of static friction plates and a plurality of dynamic friction plates which are arranged in a staggered mode; the static friction plate does not rotate relative to the brake cavity; the inner side of the dynamic friction plate is sleeved on the spline tooth part; when the friction plate set is extruded by the axis, the static friction plate and the dynamic friction plate are tightly attached to each other; when the friction plate set relieves the axial line extrusion, the static friction plate and the dynamic friction plate are separated from each other;

the outer side of the first piston sleeve is attached to the brake cavity; a second step surface is arranged on the outer side surface of the first piston sleeve, a first oil cavity is formed between the first step surface and the second step surface at an interval, and the first oil cavity is communicated with the first oil channel; the inner side surface of the first piston sleeve is provided with a third step surface and a fourth step surface; the first piston sleeve is also provided with a third oil passage;

the stop block is fixedly arranged in the brake cavity and is arranged on one side, away from the friction plate set, of the first piston sleeve;

the two ends of the first spring are respectively connected with the first piston sleeve and the stop block;

the outer side of the second piston sleeve is attached to the first piston sleeve and arranged between the third step surface and the friction plate group; a fifth step surface is arranged on the outer side of the second piston sleeve, a second oil cavity is formed between the fourth step surface and the fifth step surface at an interval, and the second oil cavity is communicated with the third oil channel;

the transmission sleeve is rotatably arranged on the brake seat and is connected with the forklift hub;

a drive shaft rotating within the drive sleeve;

the planetary reduction gear set is used for the transmission connection between the transmission sleeve and the transmission shaft;

the input end of the motor and the transmission shaft are respectively connected with the two end keys of the connecting sleeve.

Furthermore, connecting parts protruding outwards are arranged on two sides of the static friction plate; the friction plate group also comprises a connecting rod which is inserted into all the connecting parts; the friction plate set further comprises a plurality of second springs, the second springs are sleeved on the connecting rod, and each second spring is arranged between every two adjacent static friction plates.

Further, the second spring is a conical spring, and one end with a small diameter faces the second piston sleeve.

Furthermore, a plurality of air guide grooves extending along the radial direction are arranged on the end faces of two ends of the dynamic friction plate, and one ends of the air guide grooves extend to the side face of the dynamic friction plate; one end of the air guide groove close to the outer side is arranged in a bending mode, and the bending direction is the steering direction of the dynamic friction plate when the forklift moves forwards.

Furthermore, annular grooves are formed in the end faces of the two ends of the dynamic friction plate and communicated with one ends, close to the inner sides, of the air guide grooves.

Furthermore, the annular groove is provided with a chamfer structure close to the inner wall of the connecting sleeve.

Furthermore, a first gear ring and a second gear ring are arranged on the inner wall of the transmission sleeve; the side surface of the transmission shaft is provided with a first tooth part;

the planetary reduction gear set includes:

a first wheel disc rotating within the drive sleeve; a plurality of rotatable first gears are arranged on the first wheel disc, and two sides of each first gear are respectively meshed with the first gear ring and the first tooth part;

the middle shaft sleeve is sleeved on the outer side of the transmission shaft, one end of the middle shaft sleeve is in key connection with the first wheel disc, and the outer side of the middle shaft sleeve is provided with a second tooth part;

the second wheel disc is fixedly arranged on the brake seat; and a plurality of rotatable second gears are arranged on the second wheel disc, and two sides of each second gear are respectively meshed with the second gear ring and the second tooth part.

Furthermore, a connecting flange used for being connected with a forklift hub is arranged on the outer side of the transmission sleeve, and the connecting flange is arranged on one side, facing the brake seat, of the second wheel disc.

Further, the driving sleeve comprises a first section and a second section which are fixedly connected into a whole, the first toothed ring is arranged on the first section, and the second toothed ring is arranged on the second section.

The invention also provides a use method of the electric forklift walking speed reducer, which is suitable for the electric forklift walking speed reducer and comprises the following steps:

parking and braking: the motor is stopped, and the first oil duct and the second oil duct are not filled with oil; the first spring directly pushes the first piston sleeve to enable the second piston sleeve to be attached to and extruded from the friction plate set, and the static friction plate and the dynamic friction plate in the friction plate set are attached to enable the connecting sleeve to be incapable of rotating, so that parking braking of the forklift is realized;

and (5) normal driving: oil is filled into the first oil duct, oil is not filled into the second oil duct, and the motor is started; the oil in the first oil cavity pushes the first piston sleeve to the stop block, the second piston sleeve moves along with the first piston sleeve and releases the extrusion on the friction plate group, the static friction plates and the dynamic friction plates are separated, the connecting sleeve normally rotates, and then the motor is started to drive the forklift to travel;

and (3) service braking: oil is injected into the first oil channel and is injected into the second oil channel; the oil in the second oil cavity pushes the second piston sleeve to be attached to and extruded by the friction plate set, and the static friction plate and the dynamic friction plate in the friction plate set are attached to enable the connecting sleeve to be incapable of rotating, so that the running brake of the forklift is realized.

Through the technical scheme of the invention, the following technical effects can be realized:

1. the speed reducer combines the two pistons of the first piston sleeve and the second piston sleeve, and can ensure that the friction plate group is in an extruded state when the forklift stops or suddenly fails to cause the forklift equipment to stop and cannot provide power, so that the safety of the forklift during parking can be ensured;

2. when a forklift needs to brake in the running process of the forklift, the speed reducer performs braking in a mode of injecting oil into the second oil cavity and pushing the second piston sleeve to extrude the friction plate group by using the pressure of hydraulic oil, and the second piston sleeve can be quickly pushed to be in place in an oil pressure pushing mode, so that the braking response speed is higher, and the braking sensitivity of the forklift is effectively improved;

3. according to the speed reducer, the two pistons of the first piston sleeve and the second piston sleeve are designed into a sleeve form, so that the weight of the two pistons can be reduced, the two pistons can be pushed more quickly, the first oil cavity and the second oil cavity are formed by matching of the step surfaces, the volumes of the two oil cavities are reduced, the volume of the speed reducer is reduced, the oil cavities can be filled with oil more quickly, and the response speed of the speed reducer during braking is further improved;

4. the walking brake of the speed reducer is slowly released, so that the phenomenon that the forklift is too fiercely started during walking can be avoided.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a cross-sectional view of an electric forklift walking speed reducer in an embodiment of the invention;

FIG. 2 is a side view of an electric fork lift truck walking reducer in an embodiment of the present invention;

fig. 3 is a sectional view taken at a in fig. 1 (a forklift parking state);

fig. 4 is a cross-sectional view at B of fig. 2 (normal running state of the forklift);

FIG. 5 is a cross-sectional view taken at B of FIG. 2 (a forklift service braking state);

FIG. 6 is an enlarged view at C of FIG. 3;

FIG. 7 is a cross-sectional view of a friction plate pack in an embodiment of the present invention;

FIG. 8 is an enlarged view of FIG. 7 at D;

FIG. 9 is a schematic structural diagram of a friction plate set according to an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a dynamic friction plate according to an embodiment of the present invention;

FIG. 11 is a schematic view of the airflow flow path between the static friction plates and the dynamic friction plates in an embodiment of the invention;

FIG. 12 is a structural exploded view of a planetary reduction gear set in accordance with an embodiment of the present invention;

reference numerals: the brake device comprises a hub 01, a motor 02, a brake seat 1, a brake cavity 11, a first oil passage 12, a first radial oil passage 121, a first oil inlet passage 122, a first pressure relief oil passage 123, a second oil passage 13, a second radial oil passage 131, a second oil inlet passage 132, a second pressure relief oil passage 133, a first stepped surface 14, a connecting sleeve 2, a spline tooth 21, a friction plate group 3, a static friction plate 31, a connecting portion 311, a dynamic friction plate 32, an air guide groove 321, an annular groove 322, a chamfer structure 323, a connecting rod 33, a second spring 34, a first piston sleeve 4, a second stepped surface 41, a third stepped surface 42, a fourth stepped surface 43, a third oil passage 44, a first oil cavity 45, a stop 51, a first spring 52, a second piston sleeve 6, a fifth stepped surface 61, a second oil cavity 62, a transmission sleeve 7, a first gear ring 71, a second gear ring 72, a connecting flange 73, a first segment 74, a second segment 75, a transmission shaft 8, a first gear sleeve 81, a planetary gear set 9, a first wheel disc 91, a first gear 92, a second gear ring 911, a second gear ring 921 and a second gear wheel 921.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like are based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The invention relates to an electric forklift traveling speed reducer, which comprises the following components in parts by weight as shown in figures 1 to 12:

the brake seat 1 is fixedly arranged on a forklift body; a brake cavity 11 penetrating through two ends is arranged in the brake seat 1; the brake seat 1 is also provided with a first oil duct 12 and a second oil duct 13 which are communicated with the outside and the brake cavity 11; a first step surface 14 is also arranged inside the brake seat 1;

the connecting sleeve 2 is arranged in the brake cavity 11, and a spline tooth part 21 is arranged on the circumferential outer side;

the friction plate group 3 comprises a plurality of static friction plates 31 and a plurality of dynamic friction plates 32 which are arranged in a staggered mode; the static friction plate 31 does not rotate relative to the brake cavity 11; the inner side of the dynamic friction plate 32 is provided with a key slot and is sleeved on the spline tooth part 21, so that the dynamic friction plate 32 and the connecting sleeve 2 can synchronously rotate; when the friction plate group 3 is extruded by the axis, the static friction plate 31 and the dynamic friction plate 32 are tightly attached to each other; when the friction plate group 3 releases the axial extrusion, the static friction plate 31 and the dynamic friction plate 32 are separated from each other;

the outer side of the first piston sleeve 4 is attached to the inner wall of the brake cavity 11; a second stepped surface 41 is arranged on the outer side surface of the first piston sleeve 4, a first oil cavity 45 is formed between the first stepped surface 14 and the second stepped surface 41, and the first oil cavity 45 is communicated with the first oil channel 12; the inner side surface of the first piston sleeve 4 is provided with a third step surface 42 and a fourth step surface 43; the first piston sleeve 4 is also provided with a third oil passage 44;

a stop 51 fixedly arranged in the brake chamber 11 and arranged on the side of the first piston sleeve 4 remote from the friction plate set 3;

a first spring 52 having both ends connected to the first piston housing 4 and the stopper 51, respectively; a groove structure capable of placing the first spring 52 is preferably arranged on the first piston sleeve 4 or the stop 51;

the outer side of the second piston sleeve 6 is attached to the first piston sleeve 4 and arranged between the third step surface 42 and the friction plate group 3; a fifth step surface 61 is arranged on the outer side of the second piston sleeve 6, a second oil chamber 62 is formed by the fourth step surface 43 and the fifth step surface 61 at intervals, and the second oil chamber 62 is communicated with the third oil channel 44;

the transmission sleeve 7 is rotatably arranged on the brake seat 1, is connected with the forklift hub 01 and is used for driving the forklift hub 01 to rotate;

the transmission shaft 8 rotates in the transmission sleeve 7;

the planetary reduction gear set 9 is used for the transmission connection of the transmission sleeve 7 and the transmission shaft 8;

the input end of the motor 02 and the transmission shaft 8 are respectively connected with the two ends of the connecting sleeve 2 through flat keys or splines and the like, so that the output end of the motor 02, the connecting sleeve 2 and the transmission shaft 8 synchronously rotate.

Specifically, the operating principle of the speed reducer is as follows:

when the forklift is in a parking state: as shown in fig. 3, the motor 02 is off and not providing power; at this time, no oil is injected into the first oil passage 12 and the second oil passage 13; the first spring 52 can directly push the first piston sleeve 4, so that the second piston sleeve 6 is attached to and extruded by the friction plate set 3, and the static friction plates 31 and the dynamic friction plates 32 in the friction plate set 3 are attached to prevent the connecting sleeve 2 from rotating, thereby realizing parking braking of the forklift;

when the forklift needs normal driving: as shown in fig. 4, hydraulic oil having a certain pressure is injected into the first oil passage 12, and a state where the second oil passage 13 is not filled with oil is maintained; at the moment, hydraulic oil enters the first oil chamber 45 along the first oil duct 12, the first piston sleeve 4 is pushed to the stop block 51 by the oil in the first oil chamber 45, the second piston sleeve 6 moves along with the first piston sleeve 4 and releases the extrusion on the friction plate group 3, the static friction plate 31 and the dynamic friction plate 32 are separated, the connecting sleeve 2 can normally rotate, and the motor 02 can be driven to realize the walking of the forklift when being started;

when the driving process of the forklift needs braking: as shown in fig. 5, the first oil passage 12 is kept in the oil injection state, hydraulic oil with a certain pressure is injected into the second oil passage 13, the hydraulic oil enters the second oil chamber 62 along the second oil passage 13 and the third oil passage 44, the oil in the second oil chamber 62 pushes the second piston sleeve 6 to be attached to and extruded by the friction plate set 3, the static friction plates 31 in the friction plate set 3 are attached to the dynamic friction plates 32, so that the connecting sleeve 2 cannot rotate, and the running brake of the forklift is realized. When the forklift needs to travel again, only oil needs to be injected into the second oil duct 13, so that the second piston sleeve 6 cannot be pushed any more after no oil pressure exists in the second oil chamber 62, the second piston sleeve 6 releases the extrusion on the friction plate set 3, the static friction plates 31 and the dynamic friction plates 32 are separated, the connecting sleeve 2 can rotate again, and the service braking is released.

The speed reducer combines the two pistons of the first piston sleeve 4 and the second piston sleeve 6, and when the forklift stops or suddenly fails to provide power, the friction plate set 3 is ensured to be in an extruded state, so that the safety of the forklift during parking can be ensured; when a brake is needed in the driving process, the speed reducer performs the brake in a mode of injecting oil into the second oil cavity 62 and pushing the second piston sleeve 6 to extrude the friction plate group 3 by using the pressure of hydraulic oil, the second piston sleeve 6 can be quickly pushed to the place in an oil pressure pushing mode, and compared with the existing brake structure of a single-piston structure in which the brake is performed by resetting the piston through oil pressure relief, the speed reducer has higher brake response speed and can improve the brake sensitivity of the forklift; simultaneously, this speed reducer designs into telescopic form with two pistons of first piston bush 4 and second piston bush 6, can alleviate the weight of two pistons, makes it promote more fast to form first oil pocket 45 and second oil pocket 62 through the cooperation of each ladder face, can also reduce the volume of two oil pockets when reducing the processing degree of difficulty, thereby make the oil pocket oil charge faster, further promote the response speed when this speed reducer braking, can also reduce the volume of this speed reducer simultaneously. When the service brake is released, oil is required to be decompressed, the service can be recovered after the second piston sleeve 6 is pushed open through the friction plate group 3, the whole process needs a certain time, and the static friction plate 31 and the dynamic friction plate 32 are slowly separated in the process, so that the service brake of the forklift is slowly released, and the phenomenon that the forklift is too violent in service starting can be avoided.

It is preferable to set the communication relationship of the second oil passage 13 and the third oil passage 44: when the forklift is in a parking state (i.e., the first oil passage 12 is not filled with oil, and the first piston sleeve 4 is not pushed by hydraulic oil), as shown in fig. 3, the second oil passage 13 and the third oil passage 44 are staggered and not communicated with each other; when the forklift is in a walking state (i.e., after the first oil passage 12 is filled with oil, hydraulic oil pushes the first piston sleeve 4 to abut against the stopper 51), as shown in fig. 4~5, the second oil passage 13 and the third oil passage 44 are communicated with each other. The structure can ensure that when the forklift is in a parking state, even if oil is filled into the second oil duct 13 accidentally, hydraulic oil cannot enter the second oil chamber 62, so that damage to the friction plate set 3 caused by overlarge pressure of the second piston sleeve 6 on the friction plate set 3 when the hydraulic oil enters the second oil chamber 62 is prevented, and potential safety hazards caused by the fact that the first piston sleeve 4 is pushed away from the friction plate set 3 by the hydraulic oil in the second oil chamber 62 can also be prevented; meanwhile, in the process that the first piston sleeve 4 is pushed by the hydraulic oil in the first oil chamber 45, the second piston sleeve 6 may not be pushed to abut against the third step surface 42 due to the fact that the pushing force of the friction plate group 3 is not large, and with the structure, if the first piston sleeve 4 and the second piston sleeve 6 do not move synchronously, the second oil chamber 62 is enlarged, and the second oil chamber 62 is in a closed state, the internal pressure of the second oil chamber is reduced, so that the first piston sleeve 4 and the second piston sleeve 6 can keep moving synchronously, and the suction effect is most obvious when the first piston sleeve 4 moves at the beginning, at the moment, the oil pressure pushing force on the first piston sleeve 4 is the largest, but the second piston sleeve 6 is easily moved due to inertia influence, the two piston sleeves are easily dislocated, and the second oil chamber 62 brought by the structure has the suction effect on the second piston sleeve 6, so that the second piston sleeve 6 can be started quickly.

A specific preferred structure of the first oil passage 12 is as follows: as shown in fig. 3, the first radial oil passage 121 communicating with the first oil chamber 45, the first oil inlet passage 122 having two ends respectively communicating with one side end surface of the brake shoe 1 and the first radial oil passage 121, and the first relief oil passage 123 having two ends respectively communicating with the other side end surface of the brake shoe 1 and the first radial oil passage 121 are included. The first radial oil passage 121, the first oil inlet passage 122 and the first pressure relief oil passage 123 are preferably all arranged as linear pipelines, and the first radial oil passage 121 is preferably communicated to the outer side and is blocked by a plug, so that each oil passage can be conveniently machined and formed; a pipeline joint is arranged at one end of the first oil inlet passage 122 close to the outer side, so that the first oil inlet passage can be conveniently connected with an outer side oil way and an oil pipe; one end of the first pressure relief oil passage 123 close to the outer side is provided with a pressure relief valve, and when the oil pressure in the oil passage is too large, the pressure relief valve can relieve the pressure to protect parts.

A specific preferable structure of the second oil passage 13 is as follows: as shown in fig. 4~5, there are included a second radial oil passage 131 which can communicate with the third oil passage 44, a second oil inlet passage 132 whose both ends communicate with the end surface on one side of the brake spider 1 and the second radial oil passage 131, respectively, and a second relief oil passage 133 whose both ends communicate with the end surface on the other side of the brake spider 1 and the second radial oil passage 131, respectively. The second radial oil passage 131, the second oil inlet passage 132 and the second pressure relief oil passage 133 are preferably all arranged as straight lines, and the second radial oil passage 131 is preferably communicated to the outside and blocked by plugs, so that each oil passage can be conveniently machined and formed; a pipeline joint is arranged at one end, close to the outer side, of the second oil inlet channel 132, so that the connection with an outer oil way and an oil pipe is facilitated; one end of the second pressure relief oil passage 133 close to the outside is provided with a pressure relief valve, so that when the oil pressure in the oil passage is too large, the pressure relief valve can relieve the pressure to protect parts.

The friction plate group 3 has the prior art which can be directly implemented, so the specific working principle and structure thereof are not described herein; on the basis of the existing friction plate group 3 structure, the speed reducer also improves the partial structure of the friction plate group 3 according with the use scene:

preferably, the connecting portions 311 protruding outwards are arranged on two sides of the static friction plate 31, the connecting portions 311 can enable the static friction plate 31 to be in a non-rotating structure, at this time, the static friction plate 31 can be placed in the placing cavity by arranging the placing cavity with the same section shape as that of the static friction plate 31 with the connecting portions 311, and the static friction plate 31 can be effectively prevented from rotating by blocking the connecting portions 311 through the side wall of the placing cavity; the friction plate group 3 further comprises a connecting rod 33, and the connecting rod 33 penetrates through all the static friction plates 31 to limit the moving direction of the static friction plates 31; it is preferable to set the insertion position of the connecting rod 33 at the connecting portion 311 to prevent the connecting rod 33 from affecting the rotation of the dynamic friction plate 32; the friction plate group 3 further comprises a plurality of second springs 34 which are sleeved on the connecting rod 33, and each second spring 34 is arranged between two adjacent static friction plates 31, so that the same speed can be kept when all the static friction plates 31 are close to and far away from each other, and the friction action of the dynamic friction plates 32 is prevented from being uneven, so that the friction plate group 3 shakes.

The specific shape of the connecting portion 311 may be a plurality of forms such as a triangle, a rectangle, or a semicircle, and the connecting portion 311 is optimally designed into a triangle, as shown in fig. 9, the triangle-shaped connecting portion 311 is provided with a tangential side and a vertical side, the tangential side is tangential to the side of the static friction plate 31, and the vertical side is perpendicular to the tangential side, so that when the placing cavity limits the rotation of the static friction plate 31, the vertical side becomes a contact surface with the side wall of the placing cavity, and at this time, the stress can be uniformly dispersed and transmitted to each part of the static friction plate 31, thereby improving the stability of the static friction plate 31.

The second spring 34 is preferably provided as a conical spring with the smaller diameter end facing the second piston sleeve 6, as shown in fig. 8. The conical spring can enable the force application direction of the spring to the static friction plate 31 to generate a certain inclination with the surface of the static friction plate 31; when braking, the static friction plate 31 is compressed, at the moment, the static friction plate 31 moves towards the right side of the figure, the direction of a main generated force is expanded towards the figure, and at the moment, the dynamic friction plate 32 is in a rotating state, so that the force applied to the static friction plate 31 in the direction of the expanded state can effectively improve the stability of the static friction plate 31, reduce the tendency that the static friction plate 31 rotates along with the dynamic friction plate 32, and realize quick and stable braking; when the static friction plates 31 are separated, the static friction plates 31 move towards the left side of the drawing, the direction of the main generated force is folded towards the axis of the connecting rod 33, so that the static friction plates 31 can move along the axis of the connecting rod 33 more accurately, the force is concentrated at the contact part of the static friction plates 31 and the connecting rod 33, the static friction plates 31 can be pushed quickly, and the second piston sleeve 6 can be moved and reset quickly.

Preferably, a plurality of air guiding grooves 321 extending in the radial direction are formed in the end faces of the two ends of the dynamic friction plate 32, as shown in fig. 10, and one end of each air guiding groove 321 extends to the side face of the dynamic friction plate 32, and in the process of rotating the dynamic friction plate 32, the air flow enters the air guiding grooves 321 from the end where the air guiding grooves 321 are communicated with the outside, moves to the inner side of the dynamic friction plate 32 along the air guiding grooves 321, and then blows to the static friction plate 31, as shown in fig. 11, at this time, the air flow blows off both the static friction plate 31 and the dynamic friction plate 32, so that the static friction plate 31 is prevented from being contacted by the dynamic friction plate 32 in the rotating process to affect normal rotation, and meanwhile, the flowing air flow can also play a role in heat dissipation for the inside of the speed reducer. Considering that the forklift usually runs at a high speed in a forward running state and does not run at a high speed in a reverse running state, it is preferable that one end of the air guiding groove 321 near the outer side is bent, and the bending direction is the steering direction of the movable friction plate 32 when the forklift advances, so that the air flow forming effect of the air guiding groove 321 is more obvious when the forklift advances.

Because the airflow in the speed reducer is relatively disturbed under the influence of each component, the airflow in each air guide groove 321 is difficult to keep consistent, and the dynamic friction plate 32 is easy to shake due to different blowing forces of different airflows towards the static friction plate 31. In order to solve the problem, the speed reducer is provided with annular grooves 322 on the end faces of the two ends of the dynamic friction plate 32, the annular grooves 322 are communicated with one ends of all the air guide grooves 321 close to the inner sides, so that the air flowing into the inner sides from the air guide grooves 321 cannot directly blow to the static friction plate 31, but can be gathered and mixed in the annular grooves 322 and then blown to the static friction plate 31, the air flow blowing to the static friction plate 31 forms an annular shape, and the blowing strength of the air flow of each part of the annular shape is relatively consistent, so that the friction plate 32 can be effectively prevented from shaking when rotating. Preferably, a chamfer structure 323 is arranged on the annular groove 322 near the inner wall of the connecting sleeve 2, and the chamfer structure 323 can guide the airflow blowing to the static friction plate 31 to incline towards the center of the friction plate set 3, so that the airflow turbulence caused by the mutual interference between the airflow blowing to the static friction plate 31 and the airflow flowing in the air guide groove 321 is avoided, and the friction plate 32 is further prevented from shaking.

In order to reduce the volume of the speed reducer, the speed reducer adopts a planetary reduction gear set 9 with a small volume to drive a forklift hub 01; planetary reduction gear set 9 can directly adopt the structural style of the planetary reducer among the prior art, and this speed reducer carries out the improvement that more accords with the use scene to planetary reduction gear set 9 on the basis of current planetary reducer:

a first gear ring 71 and a second gear ring 72 are arranged on the inner wall of the transmission sleeve 7; a first tooth part 81 is arranged on the side surface of the transmission shaft 8;

meanwhile, the specific structure of the planetary reduction gear set 9 is set as follows, as shown in fig. 9, and includes:

a first wheel disc 91 rotating in the driving sleeve 7; a plurality of rotatable first gears 911 are arranged on the first wheel disc 91, and two sides of each first gear 911 are respectively meshed with the first gear ring 71 and the first tooth part 81;

the middle shaft sleeve 92 is sleeved outside the transmission shaft 8, so that the middle shaft sleeve 92 and the transmission shaft 8 can independently rotate; one end of the middle shaft sleeve 92 is connected with the first wheel disc 91 through splines, flat keys and the like, so that the middle shaft sleeve 92 and the first wheel disc 91 can synchronously rotate; the outer side of the middle shaft sleeve 92 is provided with a second tooth part 921;

a second wheel disc 93 fixedly mounted on the brake base 1; the second disk 93 is provided with a plurality of rotatable second gears 931, and both sides of the second gears 931 are respectively engaged with the second ring gear 72 and the second tooth portions 921.

Specifically, the operating principle of the planetary reduction gear set 9 is as follows: since the planetary reduction gear set 9 is suitable for a forklift truck for carrying goods, a large load-bearing requirement is generated. In the speed reducer, the second wheel disc 93 is directly and fixedly arranged on the brake seat 1, so that the second wheel disc can bear larger pressure transmitted from the transmission sleeve 7; however, the gear teeth of the gears are severely worn by large pressure, and the accuracy of the transmission ratio is affected, therefore, the speed reducer is further provided with a second-stage transmission structure consisting of the first gear 911, the first gear ring 71 and the first gear portion 81, all parts of the second-stage transmission structure are mainly arranged in a rotating mode, and all parts are relatively independent from main stressed parts and cannot be subjected to overlarge load and wear, so that the accurate transmission ratio can be ensured for a long time, and the accuracy of the transmission ratio is ensured.

The connecting flange 73 for connecting with the forklift hub 01 needs to be arranged on the outer side of the transmission sleeve 7, and the most force received by the connecting flange 73 is the force in the radial direction, so the speed reducer preferably arranges the connecting flange 73 on the side of the second wheel disc 93 facing the brake seat 1, thereby transmitting the force received by the connecting flange 73 to the second gear 931 and finally to the second wheel disc 93 as much as possible and avoiding the first wheel disc 91 from receiving excessive pressure.

Preferably, the transmission sleeve 7 is arranged in a split mode, the transmission sleeve 7 is provided with a first section 74 and a second section 75 which are fixedly connected into a whole through screws or bolts, the first toothed ring 71 which is not easy to wear is arranged on the first section 74, and the second toothed ring 72 which is easy to wear is arranged on the second section 75, so that the production and assembly of the speed reducer can be facilitated, when the tooth part is damaged, the transmission sleeve 7 does not need to be integrally replaced, only the corresponding section needs to be replaced, and the cost can be greatly saved. The first section 74 and the second section 75 may be made of different materials if necessary, so that they are more suitable for the special stress situation of each section.

The invention also relates to a use method of the electric forklift walking speed reducer, which is suitable for the electric forklift walking speed reducer and comprises the following steps:

parking and braking: the motor 02 is stopped, and the first oil duct 12 and the second oil duct 13 are not filled with oil; the first spring 52 directly pushes the first piston sleeve 4, so that the second piston sleeve 6 is attached to and extruded by the friction plate set 3, and the static friction plates 31 and the dynamic friction plates 32 in the friction plate set 3 are attached to prevent the connecting sleeve 2 from rotating, thereby realizing parking braking of the forklift;

and (5) normal driving: oil is filled into the first oil duct 12, oil is not filled into the second oil duct 13, and the motor 02 is started; the oil in the first oil chamber 45 pushes the first piston sleeve 4 to the stop block 51, the second piston sleeve 6 moves along with the first piston sleeve 4 and releases the extrusion on the friction plate group 3, the static friction plates 31 are separated from the dynamic friction plates 32, the connecting sleeve 2 normally rotates, and the forklift is driven to walk;

and (3) service braking: starting the motor 02, keeping the first oil duct 12 filled with oil, and filling the second oil duct 13 with oil; the oil in the second oil chamber 62 pushes the second piston sleeve 6 to be attached to and extruded by the friction plate set 3, and the static friction plates 31 and the dynamic friction plates 32 in the friction plate set 3 are attached to each other, so that the connecting sleeve 2 cannot rotate, and the service braking of the forklift is realized.

The parking braking step, the normal running step and the running braking step are control methods of the electric forklift running speed reducer in three states, the three steps are relatively independent, no sequence limitation exists, and the steps can be switched randomly.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides an electricity drives fork truck walking speed reducer which characterized in that includes:

the brake seat (1) is arranged on a forklift body, a brake cavity (11) penetrating through two ends is arranged in the brake seat, and a first oil duct (12) and a second oil duct (13) which are communicated with the outer side and the brake cavity (11) are arranged in the brake seat; a first step surface (14) is arranged in the brake seat (1);

the connecting sleeve (2) is arranged in the brake cavity (11), and a spline tooth part (21) is arranged on the circumferential outer side;

the friction plate set (3) comprises a plurality of static friction plates (31) and a plurality of dynamic friction plates (32) which are arranged in a staggered mode; the static friction plate (31) does not rotate relative to the brake cavity (11); the spline tooth part (21) is sleeved on the inner side of the dynamic friction plate (32); when the friction plate set (3) is extruded by an axis, the static friction plate (31) and the dynamic friction plate (32) are tightly attached to each other; when the friction plate set (3) is released from axial extrusion, the static friction plate (31) and the dynamic friction plate (32) are separated from each other;

the outer side of the first piston sleeve (4) is attached to the brake cavity (11); a second step surface (41) is arranged on the outer side surface of the first piston sleeve (4), a first oil cavity (45) is formed between the first step surface (14) and the second step surface (41) at an interval, and the first oil cavity (45) is communicated with the first oil channel (12); a third step surface (42) and a fourth step surface (43) are arranged on the inner side surface of the first piston sleeve (4); the first piston sleeve (4) is also provided with a third oil channel (44);

the stop block (51) is fixedly arranged in the brake cavity (11) and is arranged on one side, away from the friction plate group (3), of the first piston sleeve (4);

the two ends of the first spring (52) are respectively connected with the first piston sleeve (4) and the stop block (51);

the outer side of the second piston sleeve (6) is attached to the first piston sleeve (4) and arranged between the third step surface (42) and the friction plate group (3); a fifth step surface (61) is arranged on the outer side of the second piston sleeve (6), a second oil cavity (62) is formed by the fourth step surface (43) and the fifth step surface (61) at an interval, and the second oil cavity (62) is communicated with the third oil channel (44);

the transmission sleeve (7) is rotatably arranged on the brake seat (1) and is connected with a forklift hub;

the transmission shaft (8) rotates in the transmission sleeve (7);

a planetary reduction gear set (9) for the transmission connection of the transmission sleeve (7) and the transmission shaft (8);

the input end of the motor and the transmission shaft (8) are respectively connected with the two end keys of the connecting sleeve (2).

2. The walking speed reducer of the electric forklift according to claim 1, wherein connecting portions (311) protruding outwards are arranged on two sides of the static friction plate (31); the friction plate group (3) also comprises a connecting rod (33) which is inserted into all the connecting parts (311); the friction plate group (3) further comprises a plurality of second springs (34) which are sleeved on the connecting rod (33), and each second spring (34) is arranged between two adjacent static friction plates (31).

3. An electrically driven forklift travel reducer according to claim 2 in which the second spring (34) is a conical spring with the smaller diameter end facing the second piston hub (6).

4. The walking speed reducer of the electric forklift according to claim 1, wherein a plurality of radially extending air guide grooves (321) are formed in end faces of two ends of the dynamic friction plate (32), and one end of each air guide groove (321) extends to the side face of the dynamic friction plate (32); one end of the air guide groove (321) close to the outer side is arranged in a bent mode, and the bending direction is the steering direction of the dynamic friction plate (32) when the forklift moves forwards.

5. The walking speed reducer of the electric forklift according to claim 4, wherein annular grooves (322) are further formed in end faces of two ends of the dynamic friction plate (32), and the annular grooves (322) are communicated with one ends, close to the inner sides, of all the air guide grooves (321).

6. The electrically driven forklift walking reducer according to claim 5, wherein the annular groove (322) is provided with a chamfer structure (323) near the inner wall of the connecting sleeve (2).

7. The walking speed reducer of the electric forklift according to claim 1, wherein a first toothed ring (71) and a second toothed ring (72) are arranged on the inner wall of the transmission sleeve (7); a first tooth part (81) is arranged on the side surface of the transmission shaft (8);

the planetary reduction gear set (9) includes:

a first wheel disc (91) rotating in the transmission sleeve (7); a plurality of rotatable first gears (911) are arranged on the first wheel disc (91), and two sides of the first gears (911) are respectively meshed with the first gear ring (71) and the first tooth part (81);

the middle shaft sleeve (92) is sleeved on the outer side of the transmission shaft (8), one end of the middle shaft sleeve is in key connection with the first wheel disc (91), and the outer side of the middle shaft sleeve is provided with a second tooth part (921);

the second wheel disc (93) is fixedly arranged on the brake seat (1); the second wheel disc (93) is provided with a plurality of rotatable second gears (931), and two sides of each second gear (931) are respectively meshed with the second gear ring (72) and the second tooth part (921).

8. The electric forklift walking speed reducer according to claim 7, wherein a connecting flange (73) for connecting with a forklift hub is arranged on the outer side of the transmission sleeve (7), and the connecting flange (73) is arranged on one side of the second wheel disc (93) facing the brake seat (1).

9. The electric drive forklift travel reducer according to claim 7, wherein the drive sleeve (7) comprises a first section (74) and a second section (75) fixedly connected as a single piece, the first toothed ring (71) being disposed at the first section (74) and the second toothed ring (72) being disposed at the second section (75).

10. The use method of the walking speed reducer of the electric forklift is characterized by being suitable for the walking speed reducer of the electric forklift as claimed in any one of claims 1~9, and comprising the following steps of:

parking and braking: the motor is stopped, and the first oil channel (12) and the second oil channel (13) are not filled with oil; the first spring (52) directly pushes the first piston sleeve (4) to enable the second piston sleeve (6) to be attached to and extruded by the friction plate set (3), and the static friction plate (31) and the dynamic friction plate (32) in the friction plate set (3) are attached to enable the connecting sleeve (2) to be incapable of rotating, so that parking braking of the forklift is achieved;

and (5) normal driving: oil is filled into the first oil duct (12), oil is not filled into the second oil duct (13), and the motor is started; oil in the first oil cavity (45) pushes the first piston sleeve (4) to the stop block (51), the second piston sleeve (6) moves along with the first piston sleeve (4) and releases the extrusion of the friction plate set (3), the static friction plate (31) is separated from the dynamic friction plate (32), and the connecting sleeve (2) normally rotates; then the motor is started to drive the forklift to walk;

and (3) service braking: oil is kept injected into the first oil channel (12), and oil is injected into the second oil channel (13); the oil in the second oil cavity (62) pushes the second piston sleeve (6) to be attached to and extruded by the friction plate set (3), and the static friction plate (31) and the dynamic friction plate (32) in the friction plate set (3) are attached to each other, so that the connecting sleeve (2) cannot rotate, and the running brake of the forklift is realized.