CN112850579A

CN112850579A - AGV fork truck of rearmounted differential drive wheel

Info

Publication number: CN112850579A
Application number: CN202110240031.4A
Authority: CN
Inventors: 石伟; 李特
Original assignee: Shenzhen Casun Intelligent Robot Co ltd
Current assignee: Shenzhen Casun Intelligent Robot Co ltd
Priority date: 2021-03-04
Filing date: 2021-03-04
Publication date: 2021-05-28

Abstract

The invention discloses an AGV forklift with a rear differential driving wheel, which comprises a forklift body, wherein a control circuit unit for automatic guiding is arranged on the forklift body, two supports for supporting the forklift body are arranged at the rear end of the forklift body in a fork manner, and fork arms which can be up and down slidably connected with the forklift body to realize lifting are arranged above the two supports; the two supports are respectively internally provided with at least one chain type driving wheel component, each chain type driving wheel component is provided with a driving wheel for contacting with the ground, and each chain type driving wheel component is independently controlled by the control circuit unit to enable the driving wheels on the two supports to form differential motion; the bottom of the vehicle body is also provided with at least one supporting wheel for contacting with the ground. The invention enables the electric forklift with the automatic guiding function to realize rear differential drive, flexibly realize walking and turning, reduce the turning radius, and ensure the ground gripping force of the driving wheel while lightening the balance weight of the forklift head.

Description

AGV fork truck of rearmounted differential drive wheel

Technical Field

The invention relates to the technical field of intelligent forklifts, in particular to an AGV forklift with a rear differential driving wheel.

Background

Along with the development of logistics and warehousing industries, electric forklifts for carrying goods in warehouses are more and more widely applied. The automatic guide module is arranged on the electric forklift, so that the electric forklift becomes an AGV forklift.

The end of the electric forklift with the fork arm is the rear end (or the tail) of the forklift, and the end of the forklift body is the front end (or the head).

The existing electric forklift driving wheel is generally driven in a single steering wheel mode, the walking and the steering of the existing electric forklift driving wheel are controlled by adopting independent motors, and meanwhile, the existing electric forklift driving wheel is generally arranged at the head part.

The driving by adopting the single steering wheel mode has the following defects:

1. the electric forklift driven by the single steering wheel is poor in walking flexibility, needs a large turning radius and a long aligning distance, and generally requires a high utilization rate of an area in an intelligent warehousing project, so that a reserved channel is not wide, and the traditional electric forklift with the single steering wheel has no competitive advantage under the condition.

2. The single steering wheel driving forklift is provided with one driving motor on the whole forklift, when the load is heavy, the power of the single driving motor needs to select high power, and the large current generated during the operation brings inconvenience to the wire profile selection and safety control.

Meanwhile, the driving wheel is arranged at the head part of the electric forklift and has the following defects:

because the load (goods) is placed at the tail part of the forklift and on the fork arm, the design of the forklift is heavier or a counterweight is added to ensure the grip force of the forklift in order to prevent the single steering wheel of the forklift part from tilting, and the power loss is increased due to the overweight of the forklift.

Therefore, the prior art has yet to be improved.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide an AGV forklift with a rear differential driving wheel, which aims to enable an electric forklift with an automatic guiding function to realize rear differential driving, flexibly realize walking and turning, reduce the turning radius, reduce the counterweight of a vehicle head and ensure the ground gripping force of the driving wheel.

In order to realize the purpose, the invention adopts the following technical scheme:

an AGV forklift with a rear differential driving wheel comprises a forklift body, a control circuit unit which is arranged on the forklift body and used for automatically guiding the forklift body, wherein,

the rear end fork of the vehicle body is provided with two brackets for supporting the vehicle body, and a fork cargo arm which can be up and down connected with the vehicle body in a sliding manner to realize lifting is arranged above the two brackets;

the two supports are respectively internally provided with at least one chain type driving wheel component, each chain type driving wheel component is provided with a driving wheel for contacting with the ground, and each chain type driving wheel component is independently controlled by the control circuit unit to enable the driving wheels on the two supports to form differential motion;

the bottom of the vehicle body is also provided with at least one supporting wheel for contacting with the ground.

Each chain type driving wheel assembly comprises a servo motor, a speed reducer, a tensioning mechanism, a main chain wheel, a driven chain wheel, a chain and a driving wheel;

the servo motor is in transmission connection with the speed reducer in the axial direction of the speed reducer, the tensioning mechanism is connected with the outer side of the speed reducer and fixes the speed reducer on the support, and the driving wheel is rotationally connected to the support;

the output end of the inner side of the speed reducer is rotatably connected with the main chain wheel, the driven chain wheel is fixed on the driving wheel, the main chain wheel is in transmission connection with the driven chain wheel through a chain, and the tensioning degree of the chain is adjusted by the tensioning mechanism.

The tensioning mechanism comprises a sliding block and a tensioning block;

the inner side surface of the sliding block is fixedly connected with the speed reducer, the outer side surface of the sliding block is fixed on the bracket, the bracket is provided with an adjusting chute which can adjust the fixed position of the sliding block on the bracket, and the rear end of the sliding block is provided with a first tensioning inclined plane;

the tensioning block comprises a fixing block and an adjusting block, the fixing block is fixed on the support, the adjusting block is installed on the fixing block, the fixing position of the adjusting block is adjustable, and a second tensioning inclined plane and a first tensioning inclined plane are arranged at the front end of the adjusting block and abutted to the chain in a propping mode.

The driving wheel is a cylindrical wide rubber wheel, and the width of the cylindrical wide rubber wheel is close to that of the support.

Wherein, the main chain wheel and the auxiliary chain wheel are both double-row chain wheel.

Wherein, the driving wheel is positioned at the middle position of the bracket in the length direction.

The lifting motor and the lead screw assembly are further arranged in the trolley body, the lifting motor is in transmission connection with the lead screw assembly, and the lead screw assembly is further connected with the fork arm to enable the fork arm to ascend and descend.

The control circuit unit comprises a main control circuit, a wireless communication circuit, a power management circuit, a battery and a driving circuit, wherein the wireless communication circuit, the power management circuit, the battery and the driving circuit are electrically connected with the main control circuit;

the power management circuit manages charging and discharging of the battery, the wireless communication circuit receives and transmits signals between the upper control platform and the main control circuit, and the main control circuit controls the driving circuit to drive the chain type driving wheel assembly.

The tail end of the bracket is provided with a specular reflection sensor which is connected with a main control circuit and used for detecting an object at the tail end of the bracket.

The upper end of the vehicle body is also provided with a laser scanner and a signal indicator light which are electrically connected with the main control circuit;

and barrier laser detectors are respectively arranged on two sides of the front end of the vehicle body and electrically connected with the main control circuit.

According to the AGV forklift with the rear differential driving wheel, the two supports at the rear end of the forklift body are respectively provided with the at least one chain type driving wheel assembly, and each chain type driving wheel assembly is independently controlled by the control circuit unit, so that differential motion is realized when the driving speeds of the chain type driving wheel assemblies on the two supports are different, the AGV forklift can flexibly realize walking and turning, the turning radius is reduced, the AGV forklift is suitable for operation in a narrow space, and the occupied space during cargo handling is reduced. Meanwhile, each chain type driving wheel assembly is provided with an independent driving motor for driving, so that the high-power driving motor of the existing single steering wheel is changed into a small motor which is shared, the working current is reduced, and convenience is brought to wire selection and safety control.

And the chain type driving wheel assembly is arranged on the support at the tail of the vehicle, namely the chain type driving wheel assembly is driven to be arranged at the rear position, so that the influence of the weight on the driving wheel is not considered at the head part, the driving resistance is smaller when the head part is lighter, the gravity center can be greatly deviated to the support after the load is forked, and the ground gripping force of the driving wheel is ensured when the load is loaded. The weight of the forklift is reduced, and the power loss caused by the self weight of the forklift is reduced.

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 of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic diagram of a first embodiment of an AGV fork truck with rear differentially driven wheels according to the present invention;

FIG. 2 is a bottom view of the structure of FIG. 1;

FIG. 3 is a schematic view of the structure of FIG. 1 from another perspective;

FIG. 4 is a schematic electrical schematic of a first embodiment of the AGV fork truck with rear differentially driven wheels of the present invention;

FIG. 5 is a first exploded schematic view of the structure of FIG. 1;

FIG. 6 is a schematic structural view of the chain drive wheel assembly of the present invention;

FIG. 7 is a schematic view of the structure of FIG. 6 from another perspective;

FIG. 8 is an exploded view of the structure of FIG. 6;

FIG. 9 is a schematic view of the structure of FIG. 1 with a fork arm removed;

FIG. 10 is an enlarged schematic view at A of FIG. 9;

FIG. 11 is a schematic view of the body of the structure of FIG. 1 with a portion of the shell removed;

fig. 12 is a second exploded view of the structure of fig. 1.

Description of reference numerals:

100-forklift, 1-car body, 2-control circuit unit, 21-main control circuit, 22-wireless communication circuit, 23-power management circuit, 24-battery, 25-drive circuit, 26-laser scanner, 27-signal indicator light, 28-obstacle laser detector, 29-specular reflection sensor, 30-ultrasonic sensor array, 3-support, 31-adjustment chute, 4-fork arm, 5-chain drive wheel assembly, 51-drive wheel, 52-servo motor, 53-reducer, 54-tensioning mechanism, 541-slide block, 5411-first tensioning inclined plane, 542-tensioning block, 5421-fixed block, 5422-adjustment block, 5423-second tensioning inclined plane, 55-main sprocket, 56-driven chain wheel, 57-chain, 58-wheel shaft, 591-induction switch, 592-first rotary disc, 6-supporting wheel, 7-lifting motor and 8-screw rod component.

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. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In the present invention, unless expressly stated or limited otherwise, the terms "connected," "secured," and the like are to be construed broadly, and for example, "connected" may be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

Referring to fig. 1 to 5, the present invention provides an AGV forklift 100 with a rear differential driving wheel, which includes a car body 1, and a control circuit unit 2 for automatic guidance is provided on the car body 1.

Two supports 3 for supporting the vehicle body are arranged at the rear end of the vehicle body 1 in a fork mode, and a fork cargo arm 4 which can be connected with the vehicle body 1 in a vertically sliding mode to achieve lifting is arranged above the two supports. In the present invention, one end of the forklift body 1 of the forklift 100 is a front end (or a front end), and one end of the forklift arm 4 is a rear end (or a rear end). Two supports 3 are arranged at the left and right sides of the rear end of the vehicle body 1, when goods are placed on the fork arm 4 above the supports, the gravity of the goods is applied to the fork arm 4 and is transmitted to the supports 3, and the supports 3 play a supporting role. The fork end of the fork arm 4 is divided into two parts which are arranged left and right, and a lifting mechanism is arranged in the vehicle body 1 of the forklift truck and is in transmission connection with the fork arm 4 to drive the fork arm 4 to lift so as to fork goods.

As shown in fig. 1, at least one chain driving wheel assembly 5 is accommodated in each of the two supporting frames 3 of the present invention, each chain driving wheel assembly 5 is provided with a driving wheel 51 for contacting with the ground, and each chain driving wheel assembly 5 is independently controlled by the control circuit unit 2 to enable the driving wheels 51 of the two supporting frames 3 to perform differential motion. The bottom of the vehicle body 1 is also provided with at least one support wheel 6 for contacting the ground. Preferably, as shown in fig. 2 and 3, the bottom of the vehicle body 1 of the present invention is provided with two support wheels 6. The supporting wheels 6 can be universal wheels.

The forklift 100 of the present invention supports the whole forklift 100 by the driving wheels 51 separately provided on both sides of the rear end of the forklift 100 together with the support wheels 6 at the bottom of the body 1.

Meanwhile, the chain type driving wheel assemblies 5 on the left bracket 3 and the right bracket 3 are respectively and independently controlled by the control circuit unit 2 and can be driven independently, so that the rotating speeds of the driving wheels 51 on the chain type driving wheel assemblies can be independently controlled, and the chain type driving wheel assemblies can flexibly walk forwards and backwards and steer in a differential mode. Compared with the electric forklift in the prior art, the AGV forklift 100 disclosed by the invention can flexibly realize walking and turning, reduces the turning radius, is suitable for operation in a narrow space, and reduces the occupation of the forklift to the space during cargo transportation.

Meanwhile, each chain type driving wheel assembly 5 is driven by independent control, so that each chain type driving wheel assembly 5 is provided with an independent driving motor for driving, the high-power driving motor of a single steering wheel in the prior art is changed into a mode that two small motors are shared, the working current of a single motor is reduced, and convenience is brought to wire material type selection and safety control of a circuit part on the forklift 100.

Thirdly, the chain type driving wheel assembly 5 is arranged on the bracket 3 at the tail of the vehicle, and is installed at the rear position which is equivalent to the driving of the forklift 100 of the invention, so that the influence of the weight on the driving wheel is not considered at the head part, the lighter the head is, the smaller the driving resistance is, the gravity center can be greatly deviated to the bracket 3 after the forklift is used for forking the load, and the ground gripping force of the driving wheel 51 is ensured during the load. The weight of the forklift is reduced, and the power loss caused by the self weight of the forklift 100 is reduced.

Specifically, as shown in fig. 6 to 8, each of the chain drive wheel assemblies 5 of the forklift 100 of the present invention includes a servo motor 52, a reducer 53, a tensioning mechanism 54, a main sprocket 55, a sub sprocket 56, a chain 57 and a drive wheel 51.

The servo motor 52 is drivingly connected to the reduction gear 53 in the axial direction of the reduction gear 53, the tension mechanism 54 is connected to the outside of the reduction gear 53 and fixes the reduction gear 53 to the frame 3, and the drive wheel 51 is rotatably connected to the frame 3. The driving wheel 51 is mounted on the frame 3 through a wheel shaft 58 penetrating therein, and the driving wheel 51 rotates on the wheel shaft 58.

The servo motor 52 can precisely control the rotation speed to flexibly control the movement of the forklift 100.

The output end of the inner side of the speed reducer 53 is rotatably connected with the main chain wheel 55, the auxiliary chain wheel 56 is fixed on the driving wheel 51, the main chain wheel 55 and the auxiliary chain wheel 56 are in transmission connection through a chain 57, and the tensioning mechanism 54 adjusts the tensioning degree of the chain 57.

The tensioning mechanism 54 is provided to facilitate installation of the chain drive mechanism of the present invention, while allowing for easy adjustment of the tightness of the chain.

The invention adopts chain transmission, has the advantages of large transmission force, no slippage and the like, and is suitable for the fork transportation of heavy objects.

Further, as shown in fig. 6 and 8, the tensioning mechanism 54 of the present invention includes a slide block 541 and a tensioning block 542.

The inner side surface of the sliding block 541 is fixedly connected with the speed reducer 53, and the outer side surface thereof is fixed on the bracket 3. As shown in fig. 9 and 10, the bracket 3 of the present invention is provided with an adjusting slide groove 31 for adjusting the fixed position of the sliding block 541 on the bracket 3, and the rear end of the sliding block 541 is provided with a first tightening slope 5411.

The adjusting slide 31 allows the fixed position of the sliding block 541 and the speed reducer 53 fixedly connected to the sliding block 541 on the bracket 3 to be adjusted, thereby adjusting the tightness of the chain 57.

Tensioning block 542 includes fixed block 5421 and regulating block 5422, fixed block 5421 is fixed in support 3, regulating block 5422 installs on fixed block 5421 and fixed position is adjustable, regulating block 5422's front end is provided with second tensioning inclined plane 5423 and first tensioning inclined plane 5411 butt will the tensioning of chain 57. The position of the adjustment block 5422 is changed so that the abutment position of the second tightening slope 5423 with the first tightening slope 5411 is adjustable.

The second tensioning inclined surface 5423 abuts against the first tensioning inclined surface 5411, so that the phenomenon that the speed reducer 53 of the forklift 100 moves towards the rear end to cause the chain 57 to loosen during the operation process can be effectively prevented.

Preferably, the driving wheel 51 of the present invention is a cylindrical wide rubber wheel having a width close to the width of the bracket 3. Thus, the driving wheel 51 of the present invention has a larger contact area with the ground compared to the prior art, and thus, the supporting stability and the gripping ability are enhanced.

Preferably, the main sprocket 55 and the auxiliary sprockets 56 of the present invention are double-row sprockets, and correspondingly, the chain 57 is a double chain, which can increase the transmission stability, reduce the stress on a single chain, and prolong the service life of the chain.

Preferably, the driving wheel 51 of the present invention is located at a middle position in the length direction of the bracket 3. After the goods are placed on the fork arms 4, the stress on the supports 3 on the two sides of the driving wheel 51 is balanced, and the driving action of the chain type driving wheel assembly 5 on the whole forklift 100 is facilitated.

As shown in fig. 11, a lifting motor 7 and a screw rod assembly 8 are further arranged in the AGV forklift 100 body 1, the lifting motor 7 is in transmission connection with the screw rod assembly 8, and the screw rod assembly 8 is further connected with the fork arm 4 to enable the fork arm 4 to lift up and down. The lifting motor 7 and the screw rod assembly 8 form a lifting mechanism in the AGV forklift 100 body 1.

As shown in fig. 4, the control circuit unit 2 of the AGV forklift 100 according to the present invention includes a main control circuit 21, a wireless communication circuit 22 electrically connected to the main control circuit 21, a power management circuit 23, a battery 24, and a driving circuit 25, and the driving circuit 25 outputs a driving current to the chain drive wheel assembly 5.

The power management circuit 23 manages charging and discharging of the battery 24, the wireless communication circuit 22 transmits and receives signals between the upper control platform and the main control circuit 21, and the main control circuit 21 controls the driving circuit 25 to drive the chain type driving wheel assembly 5. In the embodiment of the present invention, the battery 24 may be a 48V/24Ah lithium ion battery.

The control circuit unit 2 receives wireless signals of an upper control platform such as a control center through the wireless communication circuit 22, obtains a navigation track after the signals are processed by the main control circuit 21, drives the driving wheels 51 of the chain driving wheel assemblies 5 on the two supports 3 through the driving circuit 25, realizes movement such as forward movement, backward movement and turning, and feeds back position information to the upper control platform in time.

Preferably, the wireless communication circuit 22 of the present invention is provided with a WIFI module, and/or a bluetooth module, and/or a 5G communication module. Therefore, the wireless communication connection with the upper control platform can be realized through various wireless networks.

Preferably, as shown in fig. 11, the end of the rack 3 of the AGV forklift 100 of the present invention is provided with a mirror reflection sensor 29 connected to the main control circuit 21 for detecting an object at the end of the rack 3. When the forklift 100 moves to the area where the goods are to be transported for forking, the specular reflection sensor 29 detects the object at the bottom of the goods, so that the fork arm 4 can correctly fork into the neutral position at the bottom of the goods, such as the neutral position of the goods shelf. The bracket 3 and the fork arm 4 are prevented from being damaged by collision.

As shown in fig. 12, the AGV forklift 100 of the present invention further includes a laser scanner 26 and a signal indicator 27 electrically connected to the main control circuit 21 at the upper end of the car body 1; thus, the AGV fork 100 with the rear differential drive wheel according to the present invention can perform the position detection by the laser scanner 26 during the transportation operation to perform the laser navigation, and perform the safety range confirmation and the signal prompt to ensure the safety of the automatically transported goods.

Preferably, the two sides of the front end of the body 1 of the forklift 100 are respectively provided with an obstacle laser detector 28 electrically connected with the main control circuit 21. The obstacle laser detector 28 detects whether an obstacle appears in front of the forklift in time during the walking process of the forklift, and adjusts the navigation path in time.

Further, the invention is also provided with an ultrasonic sensor array 30, the ultrasonic sensor array 30 can avoid the interference of light rays by detecting through ultrasound, and the combination with the obstacle laser detector 28 can enhance the obstacle avoidance effect of the forklift 100.

AGV forklift 100 with rear differential drive wheels of the present invention:

the speed and the direction of the two motors can be directly controlled by the differential driving of the two chain type driving wheel assemblies 5 to realize the motion postures of straight movement, reverse movement, turning, in-situ rotation and the like of the forklift, and the flexibility of the forklift is greatly improved.

Meanwhile, the differential driving assembly of the AGV forklift 100 of the invention consists of two chain type driving wheel assemblies, so that the high-power traveling motor of the single steering wheel is divided by two small motors, the working current is reduced, and convenience is brought to the wire rod type selection and the safety control.

Thirdly, the two chain driving wheel assemblies 5 of the AGV forklift 100 are arranged on the support 3 at the tail part of the forklift 100, the influence of weight on the driving wheels is not considered in the design of a head, the driving resistance is smaller when the head is lighter, and the gravity center can greatly shift to the support after the load is forked, so that the ground gripping force of the driving wheels 51 during the load is ensured, the weight of the head is reduced, the power loss caused by the dead weight of the forklift 100 is reduced, and the driving performance and the utility of the forklift 100 are improved.

The above description is only for clearly illustrating the invention and is not therefore to be considered as limiting the scope of the invention, and all embodiments are not intended to be exhaustive, and all equivalent structural changes made by using the technical solutions of the present invention or other related technical fields directly/indirectly applied under the concept of the present invention are included in the scope of the present invention.

Claims

1. An AGV forklift with a rear differential driving wheel, which comprises a forklift body, wherein a control circuit unit for automatic guiding is arranged on the forklift body,

2. The AGV fork lift truck with rear differentially driven wheels according to claim 1, wherein each chain drive wheel assembly comprises a servo motor, a speed reducer, a tensioning mechanism, a main sprocket, a secondary sprocket, a chain and a drive wheel;

3. The AGV forklift with rear differentially driven wheel according to claim 2, wherein the tensioning mechanism comprises a slide block and a tensioning block;

4. AGV fork truck with rear differential drive wheels according to claim 1, characterized in that the drive wheels are cylindrical wide rubber wheels with a width close to the width of the carriage.

5. The AGV forklift with rear differential drive wheel according to claim 1, wherein said master and slave sprockets are double chain sprockets.

6. AGV fork lift truck with rear differentially driven wheels according to claim 1, characterised in that the drive wheels are located in the middle of the length of the carriage.

7. The AGV forklift with the rear differential driving wheel as claimed in claim 1, wherein a lifting motor and a screw rod assembly are further arranged in the forklift body, the lifting motor is in transmission connection with the screw rod assembly, and the screw rod assembly is further connected with the fork arm so that the fork arm can lift up and down.

8. The AGV forklift with the rear differential driving wheel according to claim 1, wherein the control circuit unit comprises a main control circuit, a wireless communication circuit, a power management circuit, a battery and a driving circuit, wherein the wireless communication circuit, the power management circuit, the battery and the driving circuit are electrically connected with the main control circuit, and the driving circuit outputs driving current to the chain type driving wheel assembly;

9. The AGV forklift with the rear differential drive wheel of claim 8, wherein the end of the rack is provided with a mirror reflection sensor connected with the main control circuit for detecting the object at the end of the rack.

10. The AGV forklift with the rear differential driving wheel as claimed in claim 8, wherein the upper end of the vehicle body is further provided with a laser scanner and a signal indicator light which are electrically connected with the main control circuit;