Lifting mechanism arranged in fork leg of automatic guided vehicle

Abstract

The invention provides a lifting mechanism arranged in a fork leg of an automatic guided vehicle. The lifting mechanism comprises an oil cylinder, a jacking pull rod, a swing arm assembly and a guide plate. A lifting shaft of the jacking pull rod is arranged in a groove body of the guide plate, the swing arm assembly is connected with the lifting shaft, a piston of the oil cylinder can drive the jacking pull rod to enable the lifting shaft to move in the groove body, then the swing arm assembly is driven to swing, lifting of the lifting mechanism is achieved, and when the lifting mechanism lifts goods, shaking of the goods in the lifting process can be avoided; and the stability in the lifting process is better.

Description

[0001] Divisional Application Statement

[0002] This application is a divisional application of the Chinese invention patent application with the invention name “An Unmanned Guided Vehicle” and application number 201910004020.9 filed on January 3, 2019. Technical Field

[0003] The invention relates to the technical field of transport vehicles, and in particular to a lifting mechanism arranged in a fork leg of an unmanned transport vehicle. Background Art

[0004] An Automated Guided Vehicle (AGV) is a transport vehicle equipped with an electromagnetic or optical automatic guidance device that can travel along a specified guide path and has safety protection and various transfer functions. It is a transport vehicle that does not require a driver in industrial applications and uses a rechargeable battery as its power source. Generally, its route and behavior can be controlled by a computer, or its route can be established using an electromagnetic path-following system. However, existing unmanned transport vehicles are prone to tilt and vibration when driving on uneven roads, causing the goods on the fork legs to tip over. They are also prone to shaking when lifting goods, and have poor stability. Summary of the invention

[0005] In order to solve the problems of the prior art, the present invention provides a lifting mechanism arranged in a fork leg of an unmanned guided vehicle, which has better stability when lifting goods.

[0006] The specific technical solution is as follows: The lifting mechanism provided in the fork leg of the unmanned transport vehicle includes:

[0007] Oil cylinder;

[0008] Lifting rod;

[0009] Swing arm assembly;

[0010] Guide plate;

[0011] The lifting shaft of the lifting rod is arranged in the groove body of the guide plate, and the swing arm assembly is connected to the lifting shaft. The piston of the oil cylinder can drive the lifting rod to move the lifting shaft in the groove body, thereby driving the swing arm assembly to swing, thereby realizing the lifting and lowering of the lifting mechanism.

[0012] Preferably, the swing arm assembly includes a first swing arm, a second swing arm, a main shaft and a swing arm shaft, the first swing arm and the second swing arm are connected through the swing arm shaft, the main shaft is fixed on the fork leg, one end of the first swing arm is connected to the main shaft, and one end of the second swing arm is connected to the lifting shaft.

[0013] Further preferably, relative rotation is generated between the first swing arm and the second swing arm through the swing arm shaft.

[0014] Further preferably, the lifting mechanism includes an upper top plate which is connected to the second swing arm and also connected to the lifting plate of the fork leg. When hydraulic oil enters the oil cylinder, the piston moves, driving the jacking pull rod to move, causing the lifting shaft to move back and forth in the groove body, and at the same time driving the second swing arm to move, so that the upper top plate moves upward.

[0015] Further preferably, the lifting mechanism further includes an upper limit proximity switch and a lower limit proximity switch. The first swing arm has a notch which is correspondingly arranged with the upper limit proximity switch, and the lower limit proximity switch is correspondingly arranged with the upper top plate.

[0016] Further preferably, during the rising process of the upper top plate, as the first swing arm rotates around the main shaft, the notch is gradually filled. When the edge of the notch reaches half of the upper limit switch, an induction output signal is generated, and at this time the upper top plate rises to the highest position.

[0017] Preferably, the lifting mechanism further includes a spring. One end of the spring is connected to the lifting mechanism, and the other end is connected to the fork leg. When the lifting mechanism rises, the spring is stretched to accumulate elastic force. When the lifting mechanism descends, the elastic force of the spring assists the lifting mechanism to reset.

[0018] Preferably, the groove body is a kidney-shaped groove extending in the front-rear direction.

[0019] Technical effects of the present invention: The lifting mechanism provided in the fork leg of the automatic guided vehicle of the present invention includes: an oil cylinder, a jacking pull rod, a swing arm assembly, and a guide plate; wherein, the lifting shaft of the jacking pull rod is arranged in the groove body of the guide plate, the swing arm assembly is connected to the lifting shaft, and the piston of the oil cylinder can drive the jacking pull rod to move the lifting shaft in the groove body, thereby driving the swing arm assembly to swing, realizing the lifting of the lifting mechanism. When the lifting mechanism lifts goods, it can avoid the shaking of the goods during the lifting process, making the lifting process more stable. Description of the Drawings

[0020] Figure 1 is a schematic diagram of an automatic guided vehicle according to an embodiment of the present invention.

[0021] Figure 2 is a top view of an automatic guided vehicle according to an embodiment of the present invention.

[0022] Figure 3 is a schematic diagram of a balance wheel system according to an embodiment of the present invention.

[0023] Figure 4 is a schematic diagram of the A-A cross-section in the present invention Figure 3 in the present invention

[0024] Figure 5 is an exploded view of the universal wheel in an embodiment of the present invention

[0025] Figure 6 is a schematic diagram of the fork legs in an embodiment of the present invention

[0026] Figure 7 is a schematic diagram of the lifting mechanism in an embodiment of the present invention

[0027] Figure 8 is another schematic diagram of the lifting mechanism in an embodiment of the present invention

[0028] Figure 9 is a schematic diagram of the drive mechanism in an embodiment of the present invention Detailed implementation manners

[0029] Next, with reference to the examples, the substantial features and advantages of the present invention will be further described, but the present invention is not limited to the listed embodiments

[0030] As Figures 1 to 9 shown, an automated guided vehicle in this embodiment includes a body 1 and fork legs 2, and the fork legs 2 are connected to the body 1. The body is provided with a balance wheel system, and the balance wheel system includes balance wheel assemblies 3. Two groups of balance wheel assemblies 3 are arranged on both sides of the body 1. The balance wheel assembly 3 includes an oil pipe 31, an oil cylinder 32 and a universal wheel 33. The oil cylinder 32 includes a floating cylinder barrel 321, a floating cylinder rod 322 and a spring 323. One end of the floating cylinder rod 322 is inserted into the floating cylinder barrel 321, and the other end is connected to the universal wheel 33. The spring 323 is located between the floating cylinder rod 322 and the floating cylinder barrel 321. Both ends of the oil pipe 31 are respectively connected to the two floating cylinder barrels 321. In the above technical solution, when the two balance wheels are in the same plane, the hydraulic oil levels in the two floating cylinder barrels 321 are equal; if the left and right balance wheels are uneven in height due to uneven ground during the movement of the automated guided vehicle, the uneven height of the left and right balance wheels causes the uneven height of the left and right floating cylinder rods, and the hydraulic oil enters the oil cylinder on the side of the low balance wheel from the oil cylinder 32 on the side of the high balance wheel through the oil pipe 31, and the spring 323 plays a buffering role in this process. Through the above technical solution, when the automated guided vehicle moves on an uneven road surface, it can keep the two sides of the body balanced, buffer the generated vibration, and make its walking smoother

[0031] In this embodiment, the universal wheel 33 includes a balance wheel 331, a support 332, a first deep groove ball bearing 333 and a balance wheel bushing 334. The balance wheel 331 is arranged in the support 332. The first deep groove ball bearing 333 is arranged on the mounting parts 4 on both sides of the support 332. The balance wheel bushing 334 passes through the first deep groove ball bearing 333 and the balance wheel 331 and is locked by a hexagon head bolt 5. Through the above technical solution, the balance wheel can be easily assembled and rolls more flexibly.

[0032] In this embodiment, the universal wheel 33 includes a thrust ball bearing 335, a balance wheel bearing seat 336, a second deep groove ball bearing 337 and a straight-through oil cup 338. The thrust ball bearing 335 is arranged on the positioning seat 6 at the top of the support 332. The balance wheel bearing seat 336 is connected to the support and houses the thrust ball bearing 335. The straight-through oil cup 338 is connected to the balance wheel bearing seat 336. The second deep groove ball bearing 337 is connected to the support. Through the above technical solution, the balance wheel can rotate around the vertical axis to achieve rotation in different directions.

[0033] In this embodiment, a lifting mechanism 7 is provided in the fork leg 2. The lifting mechanism 7 includes an oil cylinder 71, a lifting pull rod 72, a swing arm assembly 73 and a guide plate 74. The lifting shaft 721 of the lifting pull rod 72 is arranged in the groove body 741 of the guide plate 74. The swing arm assembly 73 is connected to the lifting shaft 721. The piston of the oil cylinder 71 drives the lifting pull rod to make the swing arm assembly 73 swing. In the above technical solution, the piston of the oil cylinder can drive the lifting pull rod, so that the lifting shaft can move in the groove body 741, and the lifting shaft drives the swing arm assembly to swing, so that the lifting mechanism can be lifted and lowered.

[0034] In this embodiment, the swing arm assembly 73 includes a first swing arm 731, a second swing arm 732, a main shaft 733 and a swing arm shaft 734. The first swing arm 731 and the second swing arm 732 are connected by the swing arm shaft 734. The main shaft 733 is fixed on the fork leg 2. One end of the first swing arm 731 is connected to the main shaft 733. One end of the second swing arm 732 is connected to the lifting shaft 721. In the above technical solution, relative rotation is generated between the first swing arm and the second swing arm through the swing arm shaft.

[0035] In this embodiment, the lifting mechanism 7 includes an upper top plate 75. The upper top plate 75 is connected to the second swing arm 732, so that the upper top plate can be lifted and lowered. In this embodiment, the upper top plate is connected to the lifting plate 10 of the fork leg, so as to realize the lifting of the goods on the fork leg.

[0036] Specifically, the lifting principle of the lifting mechanism in this embodiment is as follows: The hydraulic pump station installed in the machine body supplies hydraulic oil into the oil cylinder 71. The piston of the oil cylinder moves, and the piston drives the jacking pull rod 72 to move through the top plate 79. The jacking pull rod drives the lifting shaft 721 to move back and forth in the groove body 741, and at the same time drives the second swing arm 732 to move; while the main shaft 733 is fixed, the first swing arm 731 and the second swing arm 732 are connected and rotated through the swing arm shaft 734, so the second swing arm 732 will drive the upper top plate 75 to move upward, achieving the purpose of lifting the platform from low to high; conversely, when the oil inlet of the oil cylinder is connected to the oil cylinder, due to the gravity of the goods and the platform itself, the hydraulic oil in the oil cylinder flows out from the lower end of the oil cylinder plunger and returns to the fuel tank in the machine body, and the second swing arm moves along the reverse trajectory of the lifting action, and finally the platform descends to the limit position. The hydraulic pump station in the machine body in this embodiment can refer to the patent with the application number 201810844219.8 applied by the applicant.

[0037] In this embodiment, the lifting mechanism 7 includes an upper limit proximity switch 76 and a lower limit proximity switch 77. The first swing arm 731 has a notch 735, and the notch 735 is correspondingly arranged with the upper limit proximity switch 76, and the lower limit proximity switch 77 is correspondingly arranged with the upper top plate 75. Through the above technical solution, the limit control of the lifting mechanism can be realized, and the specific principle is as follows: When the upper top plate 75 of the lifting mechanism does not rise, due to the notch 735 on the first swing arm 731, the upper limit proximity switch 76 has no induction within the effective range and no signal is output; during the rising process, as the first swing arm 731 rotates around the main shaft 733 of the lifting mechanism, the notch is gradually filled. When the edge of the notch reaches half of the upper limit switch, an induction output signal is generated, and at this time the upper top plate 75 rises to the highest position; when the mechanism does not rise, the upper top plate 75 can be sensed by the lower limit proximity switch, and a signal is output. When the upper top plate 75 exceeds the sensing range of the lower limit proximity switch after the mechanism rises, no induction signal is output.

[0038] In this embodiment, the lifting mechanism 7 includes a spring 78. One end of the spring 78 is connected to the lifting mechanism, and the other end is connected to the fork leg 2. By setting the spring, when the lifting mechanism rises, the spring stretches and accumulates elastic force; when the lifting mechanism descends, the elastic force of the spring can assist the lifting mechanism to reset.

[0039] In this embodiment, a driving mechanism 8 is provided in the fork legs 2. The driving mechanism 8 includes a servo motor 81, a speed reducer 82, a chain 83, a driving wheel 84, a first sprocket 85 and a second sprocket 86. The servo motor 81 is connected to the speed reducer 82, the first sprocket 85 is connected to the speed reducer 82, the second sprocket 86 is connected to the driving wheel 84, and the chain 83 is arranged between the first sprocket 85 and the second sprocket 86. In the above technical solution, when the servo motor 81 rotates, the torque is increased by the speed reducer 82 and the first sprocket 85 is driven to rotate. The first sprocket 85 drives the chain 83 to rotate, the chain 83 drives the second sprocket 86 to rotate, and finally the second sprocket 86 drives the driving wheel to rotate. The advantage of the above technical solution is that the rotation of the driving wheel can be realized and the assembly process can be simplified.

[0040] In this embodiment, an anti-collision sensor 9 is provided at the end of each fork leg 2. By setting the anti-collision sensor, it is possible to prevent the automatic guided vehicle from colliding with obstacles when moving forward.

[0041] An automatic guided vehicle in this embodiment can reduce the inclination and vibration of the vehicle during travel through a balance wheel system, avoiding the dumping of goods; in addition, the lifting of goods can be realized through a lifting mechanism, and the shaking of the goods during lifting can be avoided, making the lifting process more stable.

[0042] It should be noted that the above preferred embodiment is only used to illustrate the technical concept and characteristics of the present invention, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. It cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A lifting mechanism disposed inside the fork legs of an automated guided vehicle, comprising: an oil cylinder; a jacking pull rod; a swing arm assembly; a guide plate; characterized in that: the lifting shaft of the jacking pull rod is disposed inside the groove of the guide plate, the swing arm assembly is connected to the lifting shaft, and the piston of the oil cylinder can drive the jacking pull rod to move the lifting shaft inside the groove, thereby driving the swing arm assembly to swing and realizing the lifting of the lifting mechanism.

2. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 1, characterized in that: the swing arm assembly includes a first swing arm, a second swing arm, a main shaft and a swing arm shaft. The first swing arm and the second swing arm are connected by the swing arm shaft. The main shaft is fixed on the fork leg. One end of the first swing arm is connected to the main shaft, and one end of the second swing arm is connected to the lifting shaft.

3. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 2, characterized in that: relative rotation is generated between the first swing arm and the second swing arm through the swing arm shaft.

4. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 3, characterized in that: the lifting mechanism includes an upper top plate. The upper top plate is connected to the second swing arm and is also connected to the lifting plate of the fork leg. When hydraulic oil enters the oil cylinder, the piston moves, driving the jacking pull rod to move, causing the lifting shaft to move back and forth inside the groove, and at the same time driving the second swing arm to move, causing the upper top plate to move upward.

5. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 2, characterized in that: the lifting mechanism further includes an upper limit proximity switch and a lower limit proximity switch. The first swing arm has a notch, the notch is correspondingly arranged with the upper limit proximity switch, and the lower limit proximity switch is correspondingly arranged with the upper top plate.

6. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 5, characterized in that: during the upward movement of the upper top plate, as the first swing arm rotates around the main shaft, the notch is gradually filled. When the edge of the notch reaches half of the upper limit switch, an induction output signal is generated, and at this time the upper top plate rises to the highest position.

7. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 1, characterized in that: the lifting mechanism further includes a spring. One end of the spring is connected to the lifting mechanism, and the other end is connected to the fork leg. When the lifting mechanism rises, the spring stretches and stores elastic force. When the lifting mechanism descends, the elastic force of the spring assists the lifting mechanism to reset.

8. The lifting mechanism disposed inside the fork legs of an automated guided vehicle according to claim 1, characterized in that: the groove is a waist-shaped groove extending in the front-rear direction.

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