A sprocket mechanism for a trolley

Abstract

The utility model discloses a chain wheel mechanism of dolly belongs to the field of logistics equipment, and two pairs of walking wheels are arranged on one walking direction of dolly, and the walking wheel is displaced up and down on the frame simultaneously, and a motor is installed on the frame, and the motor drives the transmission rod rotation perpendicular to the walking direction, and two drive chain wheels are arranged on the both ends of transmission rod, and one passive chain wheel is arranged on the both sides of frame in the walking direction, and the outside of unilateral drive chain wheel and passive chain wheel is provided with fixed press wheel, and the outside of fixed press wheel is provided with walking wheel, and the chain is through walking wheel-fixed press wheel-drive chain wheel-passive chain wheel-fixed press wheel-walking wheel alternately and then closed loop, and one motor drives two pairs of walking wheels to rotate simultaneously. The chain wheel position is adjusted dynamically, and the chain wheel group is arranged on two kinds of moving components, and when the moving component changes the posture, the transmission is normal, so that the structure is compact, and it is favorable to realize the realization of chain transmission mode between long distance moving components.

Description

Technical Field

[0001] This utility model relates to a logistics device, specifically a sprocket mechanism for a trolley. Background Technology

[0002] Automated guided vehicles (AGVs), such as four-way vehicles and four-way shuttles, can move laterally and longitudinally along predetermined tracks to store and retrieve goods from racking locations. Four-way vehicles evolved from traditional shuttles, which can only move in a straight line and are therefore generally not used to build fully automated warehouses, but rather in conjunction with forklifts for semi-automated operations. Four-way vehicles, however, can move in four directions on a single plane and are currently the most widely used main equipment in Zhiteng's automated warehousing systems.

[0003] A four-way trolley typically has two wheel systems: one for movement in the X direction and the other for movement in the Y direction. When switching between directions, a lifting mechanism lowers the wheel set to the ground, while the other wheel set remains stationary. In existing technology, the rotation of this vertically moving wheel set is either driven by two motors on one side, or by a complex transmission mechanism that drives both wheels on one side together. This increases the cost and reliability of the equipment.

[0004] The reason why traditional chain drives cannot be used is that the core limitation of traditional chain drives is that the center position of all sprockets is fixed and the total length of the chain cannot be changed. Once the position of the sprockets is moved, the chain will inevitably become too loose or too tight, leading to skipped teeth, wear, or even breakage.

[0005] To address this, this invention proposes a "dynamic position-constant pitch line" mechanism: a symmetrical displacement design for the sprocket assembly. At least two synchronously movable sprockets are incorporated into the entire chain drive structure, and a rigid linkage mechanism forces them to move in opposite directions at equal distances. For example, when the left sprocket moves outward by ΔL, the right sprocket moves inward by ΔL simultaneously, ensuring the vector sum of the center distances between the two sprockets remains zero. Alternatively, in complex sprocket assemblies with irregular arrangements, an independent adjustable sprocket is placed on the outermost side. While the pitch line remains constant, its position is not unique; all these positions fall within its adjustable range. Simultaneously, the tensioner used in traditional chains is also present, absorbing the minute length changes caused by the chain's elastic expansion and contraction. In other words, mechanical constraints cancel out the sprocket displacements, and the tensioner compensates for microscopic deformation, achieving strict conservation of the theoretical length of the macroscopic chain.

[0006] If two moving parts are used, a single motor can drive the components within both parts to move together. The movement relationship between the two parts does not affect the movement of the components, thus eliminating the need for multiple motors for control. Utility Model Content

[0007] To solve the above-mentioned technical problems, this utility model provides a sprocket mechanism for a trolley, the technical solution of which is as follows.

[0008] A sprocket mechanism for a small vehicle includes two pairs of traveling wheels arranged in one direction of travel. These traveling wheels move up and down simultaneously on the frame. A motor is mounted on the frame, driving a transmission rod perpendicular to the direction of travel to rotate. Two drive sprockets are arranged at both ends of the transmission rod. A driven sprocket is arranged on each side of the frame in the direction of travel. A fixed pressure roller is arranged outside the drive and driven sprockets on one side, and a traveling wheel is arranged outside the fixed pressure roller. The chain alternately passes through the traveling wheel, fixed pressure roller, drive sprocket, driven sprocket, fixed pressure roller, and traveling wheel to close the loop. One motor drives both pairs of traveling wheels to rotate simultaneously.

[0009] Furthermore, an automatic tensioner is provided between the drive sprocket and the driven sprocket.

[0010] Furthermore, there are two automatic tensioning wheels.

[0011] Furthermore, the automatic tensioning wheel is finely adjusted in position.

[0012] Furthermore, the traveling wheels are mounted on a mounting plate, the mounting plate is connected to a lifting device, and the lifting device is mounted on the vehicle frame.

[0013] Furthermore, the mounting plate is equipped with a cam follower to achieve lifting and lowering.

[0014] Furthermore, two pairs of fixed wheels are provided on the other traveling direction of the vehicle frame.

[0015] Furthermore, in the direction of travel, the drive sprocket and the driven sprocket are symmetrically arranged, the two automatic tensioning wheels are symmetrically arranged, and the two fixed pressure wheels are symmetrically arranged.

[0016] Compared with the prior art, the technical solution of this utility model has the following technical effects: The sprocket mechanism of this utility model can realize chain transmission on a four-way vehicle. When the chain length remains unchanged, i.e., the chain transmission is in normal operation, the sprocket position can be dynamically adjusted, which is of great significance to the transmission layout of the equipment. The sprocket group is arranged on two moving parts. When the moving parts change their posture, the transmission is in normal operation, thus making the structure compact, or realizing the chain transmission between long-distance moving parts. (2) This scheme transforms the inherent perception that "moving the sprocket requires changing the chain length" into a variable process of "internal balance of displacement + micro-compensation" through mechanism design; it breaks the limitation of the immutable chain transmission layout and provides basic technical support for the flexible design of four-way vehicle equipment. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the transmission principle on one side of this utility model; Figure 2 This is a schematic diagram of the sprocket mechanism of a four-way vehicle; Figure 3 This is a schematic diagram of the installation of the movable mounting plate and a pair of wheels.

[0018] In this diagram, 1 represents a fixed pressure roller, 2 a driven sprocket, 3 an automatic tensioning roller, 4 a drive sprocket, 5-1 a chain posture 1, 5-2 a chain posture 2, S1 a preliminary position of the left floating sprocket, S2 a preliminary position of the right floating sprocket, S11 a adjusted position of the left floating sprocket, and S22 a adjusted position of the right floating sprocket. A1 is a fixed travel wheel, A2 is a mounting plate, and A3 is a movable travel wheel. Detailed Implementation

[0019] The specific embodiments of this utility model will be further explained below with reference to the accompanying drawings.

[0020] like Figure 1 As shown, a sprocket mechanism for a small vehicle has two pairs of traveling wheels A3 arranged in one direction of travel. The traveling wheels A3 move up and down simultaneously on the frame. A motor is mounted on the frame, and the motor drives a transmission rod perpendicular to the direction of travel to rotate. Two drive sprockets 4 are arranged at both ends of the transmission rod. A passive sprocket 2 is arranged on each side of the frame in the direction of travel. A fixed pressure roller 1 is arranged outside the drive sprocket 4 and the passive sprocket 2 on one side. The traveling wheel A3 is arranged outside the fixed pressure roller 1. The chain 5-1 / 5-2 alternately passes through the traveling wheel A3-fixed pressure roller 1-drive sprocket 4-passive sprocket 2-fixed pressure roller 1-traveling wheel A3 and then closes the loop. A motor drives the two pairs of traveling wheels A3 to rotate simultaneously.

[0021] All A3 wheels are equipped with floating sprockets, which are divided into left-side floating sprockets and right-side floating sprockets.

[0022] An automatic tensioner 3 is provided between the drive sprocket 4 and the driven sprocket 2. There are two automatic tensioners 3. The automatic tensioners 3 are finely adjusted in position. The fine adjustment of the automatic tensioners 3 can overcome the problem of tooth skipping on the gear pitch.

[0023] The traveling wheels A3 are mounted on the mounting plate A2, which is connected to a lifting device mounted on the frame. Any lifting device capable of raising or lowering the mounting plate A2 can be used. The mounting plate A2 is equipped with a cam follower to achieve lifting and lowering; this cam follower can employ a mature existing technology. Two pairs of fixed traveling wheels A1 are arranged in the other traveling direction of the frame. This arrangement allows the vehicle to travel in one direction when the lifting device lowers the movable traveling wheels, while the fixed traveling wheels remain off the ground. When switching directions, the movable traveling wheels are raised, and the fixed traveling wheels are lowered, enabling the vehicle to travel in that direction.

[0024] In the direction of travel, the drive sprocket 4 and the driven sprocket 2 are symmetrically arranged, the two automatic tensioning wheels 3 are symmetrically arranged, and the two fixed pressure wheels 1 are symmetrically arranged.

[0025] Because the mounting plate ensures perfect synchronization between lifting and lowering, when the left sprocket moves outward by ΔL, the right sprocket moves inward by ΔL simultaneously, keeping the vector sum of the center distances between the two sprockets zero. Alternatively, in complex sprocket assemblies with irregular arrangements, an independent adjustable sprocket can be placed on the outermost side. While the pitch line is constant, its position is not unique; all these positions fall within its adjustable range. Simultaneously, the tensioner used in traditional chains is also present, absorbing the minute length changes caused by the chain's elastic expansion and contraction. That is, mechanical constraints cancel out the sprocket displacements, and the tensioner compensates for micro-deformation, achieving strict conservation of the theoretical length of the macroscopic chain.

Claims

1. A sprocket mechanism for a trolley, wherein two pairs of wheels are arranged in one direction of travel of the trolley, characterized in that, The traveling wheels move up and down simultaneously on the frame. A motor is mounted on the frame, which drives a transmission rod perpendicular to the traveling direction to rotate. Two drive sprockets are set at both ends of the transmission rod. A driven sprocket is set on each side of the frame in the traveling direction. A fixed pressure roller is set outside the drive sprocket and the driven sprocket on one side. A traveling wheel is set outside the fixed pressure roller. The chain alternately passes through the traveling wheel, fixed pressure roller, drive sprocket, driven sprocket, fixed pressure roller and traveling wheel to close the loop. One motor drives two pairs of traveling wheels to rotate simultaneously.

2. The sprocket mechanism of the trolley according to claim 1, characterized in that, An automatic tensioner is provided between the drive sprocket and the driven sprocket.

3. The sprocket mechanism of the trolley according to claim 2, characterized in that, There are two automatic tensioning wheels.

4. The sprocket mechanism of the trolley according to claim 2, characterized in that, The automatic tensioning wheel is finely adjusted in position.

5. The sprocket mechanism of the trolley according to claim 1, characterized in that, The wheels are mounted on a mounting plate, which is connected to a lifting device, which is mounted on the vehicle frame.

6. The sprocket mechanism of the trolley according to claim 5, characterized in that, The mounting plate is equipped with a cam follower to achieve lifting and lowering.

7. The sprocket mechanism of the trolley according to claim 1, characterized in that, Two pairs of fixed wheels are provided on the other traveling direction of the vehicle frame.

8. The sprocket mechanism of the trolley according to claim 2, characterized in that, In the direction of travel, the drive sprocket and the driven sprocket are symmetrically arranged, the two automatic tensioning wheels are symmetrically arranged, and the two fixed pressure wheels are symmetrically arranged.

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