Precise goods placing control device for pallet fork of stacking machine
By using a pull-string encoder on the stacker crane forks to measure the fork extension distance, the problem of fork extension distance error under different load conditions is solved, enabling accurate loading and reducing the risk of accidents.
Patent Information
- Application Number
- CN202520476394.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-03-18
AI Technical Summary
The extension distance of the stacker crane forks varies under different load conditions, resulting in deviations in the placement of goods. This error is especially pronounced under heavy loads, which may lead to cumulative cargo shifting and accidents.
A pull-string encoder is used to measure the fork extension distance. Direct measurement via the pull-string eliminates errors caused by deformation of the transmission components, ensuring accurate fork loading.
It improves the accuracy of fork placement, eliminates the problem of cumulative errors from repeated placement, and reduces the risk of goods falling.
Smart Images
Figure CN223823327U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the field of automatic storage equipment, in particular to a control device for precise palletizing of a stacker fork, which can be used in a storage system with high pallet positioning accuracy. BACKGROUND
[0002] The stacker has three actions in the automatic stereoscopic warehouse, including lifting, horizontal running and fork picking. The fork picking action is the extension or retraction of the fork carrying goods. After the fork carrying goods is extended, the tray goods are placed on the shelf by cooperating with the descending movement of the car, and then the fork is retracted to the original position, completing the transfer of the tray goods from the stacker car to the shelf.
[0003] The fork is the core equipment of the stacker, and its extension accuracy determines whether the goods are placed accurately. When the fork extension accuracy is low, there is a risk of goods falling off the shelf. The fork is composed of multiple fork bodies stacked together. When the fork is extended, the bottom fork shaft rotates to drive each level of fork body to move through the chain or rack. The single-depth fork is composed of three fork bodies, and the double-depth fork is composed of four fork bodies. The upper fork body directly supports the goods, and the upper fork body is the running distance representing the extension distance of the fork. The current fork extension distance is determined by the number of rotations of the fork shaft. The shaft is equipped with an encoder to determine the position, which is converted into the extension distance by calculating the number of rotations. When the shaft rotates to the set number of rotations, it is considered that the fork has reached the target position.
[0004] In project practice, it is found that when the fork shaft rotates the same number of times, the running distance of the upper fork body is not the same when the fork is loaded and unloaded. The phenomenon that the extension distance is smaller when the fork is loaded than when it is unloaded may occur.
[0005] Reason: When unloaded, the force transmission member transmits normally. When heavily loaded, the driving force is transmitted to the upper fork through multiple fork bodies, causing elastic deformation of the force transmission member, resulting in a shorter transmission stroke (displacement or angular displacement). This phenomenon is more pronounced in heavy-duty double-depth forks, i.e., the heavier the load, the farther the palletizing distance, and the greater the error. The actual palletizing position deviation is more than 15 mm.
[0006] When repeated palletizing is required, this palletizing position deviation may accumulate and stack, causing the goods to continuously deviate to one side until the system fails or the goods fall off, causing an accident. INVENTION CONTENTS
[0007] The technical problem to be solved by the utility model is how to design a control device for precise palletizing of a stacker fork to eliminate the cumulative error of intermediate links.
[0008] The technical solution of the utility model is as follows:
[0009] A control device for precise goods placing of a stacker fork, comprising a fork body, the fork body comprising a lower fork body, a middle fork body sliding along the lower fork body, an upper fork body sliding along the middle fork body, a rope head fixing seat fixed on the upper fork body, one end of a pulling rope fixed on the rope head fixing seat, the other end of the pulling rope connected to a pulling rope encoder module, and the pulling rope encoder module fixed on the lower fork body.
[0010] The rope head fixing seat and the encoder module are on the side of the fork body.
[0011] The encoder module comprises a module base fixed on the lower fork body, and a pulling rope encoder arranged on the module base, an upstream wheel set I arranged on the module base, a downstream wheel set II arranged on the upstream wheel set I, and the upstream and downstream wheel sets I and II fixed on the lower fork body and each comprising two tangent rollers, wherein the rollers of the upstream wheel set I are cylindrical and clamp the pulling rope, and the rollers of the downstream wheel set II have grooves, and the pulling rope extends out of the grooves.
[0012] Compared with the prior art, the technical effect of the utility model is that the pulling rope encoder directly determines / measures the real position of the fork extension for goods placing by measuring the pulling rope, so that the measurement error caused by the deformation of the transmission part inside the fork due to the load of the goods is eliminated without relying on the force transmission part. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 is a schematic view of the utility model.
[0014] Figure 2 is Figure 1 a partial enlarged schematic view.
[0015] Figure 3 is a schematic view of the pulling rope encoder module. DETAILED DESCRIPTION
[0016] The utility model will be described in detail below in combination with the drawings and the specific implementation.
[0017] As Figures 1-2 a control device for precise goods placing of a stacker fork, comprising a fork body, the fork body comprising a lower fork body 1-1, a middle fork body 1-2 sliding along the lower fork body 1-1, an upper fork body 1-3 sliding along the middle fork body 1-2, a rope head fixing seat 4 fixed on the upper fork body 1-3, one end of a pulling rope 3 fixed on the rope head fixing seat 4, the other end of the pulling rope 3 connected to a pulling rope encoder module 2, and the pulling rope encoder module 2 fixed on the lower fork body 1-1.
[0018] The driving motor is a driving part for driving the lower fork body to slide, and is installed on the lower fork body, and the power is transmitted to the upper fork body through the middle fork body.
[0019] To reduce interference, both the rope head fixing seat 4 and the encoder module 2 are located on the side of the fork body.
[0020] To minimize errors, encoder module 2 includes module base 2-4, which is fixed to lower fork body 1-1. A pull rope encoder 2-1 is mounted on the module base 2-4. Upstream of module base 2-4 (following the direction of the pull rope, the rope end fixing seat 4 is upstream), there is wheel set I2-2. Upstream of wheel set I2-2, there is wheel set II2-3. Both wheel sets I2-2 and II2-3 are fixed to lower fork body 1-1. They each include two tangentially mounted rollers. The rollers of wheel set I2-2 are cylindrical, and the two rollers clamp the pull rope 3. The rollers of wheel set II2-3 have grooves, and the pull rope 3 extends out from the grooves.
[0021] Its working principle is as follows:
[0022] The motor drives the main shaft to rotate, causing the middle fork to move along the lower fork, and the upper fork to move along the middle fork. During the movement of the upper fork, the rope end fixing seat on the upper fork also moves synchronously. The relative displacement between the upper and lower forks is fed back to the controller through the rope encoder via the rope 3 pull-to-pull encoder. When the upper fork moves to the target position, the motor brakes, and the forks stop extending.
[0023] Then, the pallet on the upper fork is placed on the platform by the lowering and lowering motion of the stacker crane car. This is existing technology.
[0024] In this way, by using a pull-rope encoder to measure the pull rope, the actual position of the fork extending to release the goods can be directly determined / measured. This eliminates the reliance on force-bearing transmission components and removes measurement errors caused by deformation of the transmission components inside the forks due to the load of the goods.
[0025] Features of this application:
[0026] The problems solved by this utility model are: First, it greatly improves the accuracy of the stacker crane fork placement position, solving the problem of differences in the extension distance of empty forks and the load of different loads. Second, it eliminates the problem of cumulative error in repeated placement positions.
[0027] For other details, please refer to the existing technology.
[0028] The above description is only a preferred embodiment of the present utility model. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present utility model, and these should also be considered within the protection scope of the present utility model.
Claims
1. A control device for precise loading of goods using stacker crane forks, comprising fork bodies, the fork bodies including a lower fork (1-1), a middle fork (1-2) sliding along the lower fork (1-1), and an upper fork (1-3) sliding along the middle fork (1-2), characterized in that: A rope end fixing seat (4) is fixed on the upper fork body (1-3). The rope end fixing seat (4) fixes one end of the pull rope (3). The other end of the pull rope (3) is connected to the pull rope encoder module (2). The pull rope encoder module (2) is fixed on the lower fork body (1-1).
2. The control device for precise loading of goods onto stacker crane forks as described in claim 1, characterized in that: The rope head fixing seat (4) and the encoder module (2) are both located on the side of the fork body.
3. The control device for precise loading of goods onto stacker crane forks as described in claim 2, characterized in that: The encoder module (2) includes a module base (2-4), which is fixed on the lower fork body (1-1). A pull rope encoder (2-1) is provided on the module base (2-4). A wheel group I (2-2) is provided upstream of the module base (2-4), and a wheel group II (2-3) is provided upstream of the wheel group I (2-2). Both wheel groups I (2-2) and wheel group II (2-3) are fixed on the lower fork body (1-1). They both include two tangentially mounted rollers. The roller of wheel group I (2-2) is cylindrical, and its two wheels clamp the pull rope (3). The roller of wheel group II (2-3) has a groove, and the pull rope (3) extends out from the groove.