Patent Application
20250018514
This application claims benefit to European Patent Application No. 23184444.0, filed on Jul. 10, 2023, which is hereby incorporated by reference herein.
The present invention is related to a system for transporting a machining-related object and to a manufacturing system for machining a part by a machine tool.
Since many years, automation for machining is highly relevant to increase the productivity. Different automation systems such as robot, automatic pallet changer, and automatic tool changes are widely used in the production. In the machining workshops, a plenty of objects, for example, workpieces, produced parts, machining tools must be transported between different stations and from one machine tool to a another machine tool. Until now, transporting these objects is not fully automated and still requires manpower. Driverless transport vehicles are already widely applied in many production facilities and logistic centers. Now, they are also intended to be used in the machining workshops.
US 2020/0324976 discloses a robotic cart including a cart with four wheels and a robot which is autonomously moveable. The robot is featured with a docking module such that the cart can be docked on the robot. In this way, the robot can move with the cart to transport any objects loaded on the cart.
However, such system has several drawbacks if it is applied in the machining workshop. In order to combine with other automation systems applied for the machine tools, the robot must be positioned highly precisely. For example, if the cart carriers a pallet and the robot is moved to the proximity of the machine tool, in which the pallet should be loaded, the automatic pallet changer installed in the machine tool must be able to automatically catch the pallet on the cart. If the robot is not positioned accurately at the defined position, the automatic tool changer will not be able to grasp the pallet on the cart. It is known that the positioning accuracy of such autonomously movable robot or driverless vehicle is less than the one of the automation systems of the machine tool. Thus, measures must be taken to overcome this drawback. US 2020/0306903 discloses an arrangement for processing workpieces. The arrangement includes at least one processing machine, a machine magazine assigned to a respective processing machine for accommodating processing tools. The arrangement further includes a robot and a driverless base frame for carrying the robot.
In this system, the robot is integrated on the driverless vehicle. The driverless vehicle must carry additional loads, namely the robot, all the time, and this consumes unnecessary power for driving the vehicle.
In an embodiment, the present disclosure provides a transport system for transporting a machining-related object comprising a carrier configured to hold the machining-related object, the carrier including a plurality of receiving elements and a plurality of receiving means, an autonomous vehicle including a plurality of coupling elements configured to engage with the receiving elements of the carrier, and a lifter. The lifter is arranged at an outside of the autonomous vehicle. The lifter includes a gripper and a driver configured to move the gripper in at least one direction. The gripper is provided with a plurality of coupling means for being engaged with the receiving means of the carrier.
Subject matter of the present disclosure will be described in even greater detail below based on the exemplary figures. All features described and/or illustrated herein can be used alone or combined in different combinations. The features and advantages of various embodiments will become apparent by reading the following detailed description with reference to the attached drawings, which illustrate the following:
In an embodiment, the present invention provides a transport system for transporting a machining-related object which overcomes the drawbacks of the systems shown in the prior art. A transport system for transporting a machining-related object is also provided which has a simple construction. A transport system for transporting a machining-related object is further provided which requires low power.
An embodiment of the present invention is directed to a transporting system for transporting a machining-related object. The transporting system comprises a carrier for holding the machining-related object, an autonomous vehicle and a lifting device arranged at the outside of the autonomous vehicle. The carrier includes a plurality of receiving elements and a plurality of receiving means. The autonomous vehicle includes a plurality of coupling elements for engaging with the receiving elements of the carrier. The lifting device includes a gripper and a driving unit configured to move the gripper in the vertical direction. The gripper is provided with a plurality of coupling means for being engaged with the receiving means of the carrier.
The machining-related object includes all the objects required for machining by a machine tool or produced by machining. They can be for example, a workpiece, a machining tool, a produced part, a measuring device. In particular, the machining-related object can also be a pallet for holding an object. During machining manufacturing many machining-related object such as workpiece, machining tool, produced part must be transported from one place to another place in the manufacturing facility, in particular from one machine tool to another machine tool. The carrier can be loaded on the lifting device by a robot or manually. Then the machining-related object can be loaded on the carrier manually or automatically. For example, if the machining-related object is a pallet, an automatic pallet changer can load the pallet on the carrier. When the autonomous vehicle is driven to the defined position, the lifting device can load the carrier on the autonomous device.
The machine tool can be a machining tool for milling, laser machining, electrical discharge machining, or additive manufacturing.
The positioning accuracy of the autonomous vehicle is not sufficient to be used with the automation systems for machining, such as automatic pallet changers or robots for gripping the objects. For example, a robot is used to pick up the object carried by the autonomous vehicle. Due to the positioning inaccuracy, the autonomous vehicle cannot reach the exactly same position each time when it brings the objects to the robot. It means there is a positioning deviation of the vehicle. Thus, it can happen that the robot cannot pick up the object because the vehicle is positioned at a different position than expected. Additional sensors can be arranged to monitor the position of the vehicle to determine the position of the vehicle very precisely. However, such solution is complex and increases the costs of the system.
To solve this problem, the lifting device is arranged at the outside of the vehicle serving as an intermediate station for temporally holding the carrier. The positioning accuracy of the lifting device is much higher than the one of the autonomous vehicle. Additionally, the automation system of the machine tool, such as the robot can be calibrated once according to the position of the lifting device. Since the lifting device is fixedly mounted at one position, automation system always know exactly the position of the lifting device. When the object can be first temporally stored on the lifting device, the automation system of the machine tool can reliably pick up the objects from the lifting device or load the objects on the lifting device. The coupling mechanism between the gripper and the carrier and the coupling mechanism between the vehicle and carrier are designed in a way that the positioning inaccuracy of the vehicle can be tolerated.
The transporting system of an embodiment of the present invention compensates the positioning inaccuracy of the autonomous vehicle by providing the lifting device at the outside of the vehicle. Additionally, the transporting system has the advantage that less weight must be carried by the autonomous vehicle, since the lifting device is arranged at the outside of the vehicle.
In further, not only the coupling means are mounted on the gripper but also the coupling elements are provided on the vehicle. This is important for the application for machining, because the vehicle must transport the object from machine tool to machine tool. The carrier must be transferred from the vehicle to the lifting device and from the lifting device back to the vehicle.
When the carrier having the object thereon must be loaded from the vehicle to the lifting device, the autonomous vehicle is driven to a defined position closely to the lifting device. The lifting device is configured that the gripper is moved from a start position upwards until the coupling means are engaged with the receiving means at a second position and the gripper is moved further upwards until the coupling elements are disengaged from the receiving elements at a third position. Especially, an end position in the vertical direction is defined, and the gripper is controlled to stop at this end position. This means that the gripper is further moved upwards from the third position to the end position. Preferably, the gripper moves continuously from the start position to the end position. Alternately, the gripper stops at the second position and/or at the third position. In particular, the speed of the gripper can be constant or variable.
When the carrier having the object thereon must be loaded from the lifting device to the vehicle, the autonomous vehicle is driven to a defined position closely to the lifting device. The lifting device is configured that the gripper is moved downwards until the coupling elements are engaged with the receiving elements and the gripper is moved further downwards until the coupling means are disengaged from the receiving means.
The carrier is a stable and rigid element, because the machining-related objects can have a weight up to 200 Kg. This is also applied for the lifting device. Thus, the lifting device is designed in a way that this load can be carried.
Since the object can have a high weight, arranging the lifting device at the outside of the autonomous vehicle can dramatically reduce the load weight to be carried by the vehicle and reduce the energy consumption of the vehicle.
The autonomous vehicle can be any moving means which can move in a driverless way. The coupling elements have a simple design, thus, it allows to apply any autonomous vehicles for the transport system of embodiments of the present invention.
In some embodiments, the coupling element and the coupling mean has a top portion having a conical shape. This allows the coupling element can be easily coupled to the receiving element and the coupling means can be easily coupled to the receiving means.
In particular, the angle of the conical shaped top portion is in the range of 10 to 40 degrees. This angle eases the decoupling of the coupling elements and the receiving element and the coupling means and the receiving means, respectively. The top portion can also have other shapes, such as pyramid, cylinder, and cube.
In an embodiment, the coupling element has a supporting portion and a cone arranged on the top of the supporting portion. The supporting portion has a cylindrical shape, can also be designed having other shapes, such as a cube or triangular prism.
In an embodiment, the coupling element has a guide portion arranged between the supporting element and the cone for easily guiding the cone into the receiving element of the carrier. In particular, the guide portion has a short length to reduce the risk that the coupling element is stuck in the receiving element of the carrier. Preferably, the guide portion has a cylindrical shape. However, it can also has other shapes, such as cube or triangular prism.
In an embodiment, the supporting portion, the guiding portion and the cone are made in one piece. In an embodiment, the guiding portion and cone are made in one piece and connected with the supporting portion. All three portions can be made of the same material, for example, steel or aluminum. Preferably, the cone and the guiding portion is made in one material, for example steel to improve the strength and reduce wear and the supporting element made in another material, for example aluminum to keep the weight low.
In an embodiment, the supporting portion is designed in a manner that the carrier sits on the supporting portion when the carrier is engaged with the coupling elements. This provides a simple construction. The coupling element serves not only as an engaging element but also as a supporting element to hold the carrier.
The coupling means has a pin having a conical shape. In an embodiment, the coupling means has a guiding section, on which the pin is fixed. The guiding section stably sits on the gripper. A supporting section can be arranged below the guiding section. In this variant, the supporting section sits on the gripper. When the coupling means are engaged with the receiving means, the carrier sit on the supporting section.
In an embodiment, the pin and the guiding section are made in one piece. In an embodiment, the guiding section and pin are made in two pieces and connected together. Different materials can be used, for example, steel or aluminum. Preferably, the pin and the guiding section are made in steel to improve the strength and reduce wear.
In an embodiment, four coupling elements are provided on the autonomous vehicle and four coupling means are provided on the gripper of the lifting device. This provides the advantage that the tilting of the carrier can be avoided and the carrier can be stably held by the coupling elements and on the coupling means.
In particular, the coupling element is shorter than the coupling means. This gives the space that the gripper can enter into the space between the carrier and the top surface of the autonomous vehicle.
In an embodiment, the gripper has a U-shape and the coupling means are arranged on the two legs of U-shaped coupling means. Preferably, the coupling elements are equally allocated on the two legs. For example, two coupling elements on one leg and two coupling elements on the other leg.
In some embodiments, the coupling elements are arranged directly on the top surface of the autonomous vehicle. In order to reduce the weight to be carried by the vehicle, only the coupling elements and the carrier are mounted on the vehicle. No other elements are required. Arranging the lifting device with the gripper at the outside of the vehicle makes this possible.
In an embodiment, the receiving element is a through hole and the receiving means is a through hole. In particular, there are four holes as receiving elements and four bores as receiving means.
Preferably, two bores are designed to have a higher clearance than the other two bores.
In an embodiment, the receiving element is a recess having a cone shape and the receiving means is a recess having a cone shape. The receiving element and the receiving means can have any other shapes, provides that they can engage with the coupling element and coupling means.
The carrier can have different shapes. In an embodiment, the carrier is a plate with the receiving elements and receiving means. For example, additional holes can be bored on a typical pallet for holding a workpiece. This variant is applicable for carrying one object. The object can be a light object or heavy object.
In an embodiment, the carrier is a tray for carrying more than one object. The tray serves as a shelf. The tray comprises a tray base, a supporting element fixed on the tray base. At least one holding element is mounted on the supporting element for holding the machining-related objects. Preferably, each holding element includes a plurality of storing units for storing the objects therein. For example, the holding element can be arranged on the top of the supporting element and multiple storing units can be arranged in a row, each of which can hold a machining tool.
The lifting device includes a column provided with a guide rail, a gripper movably mounted on the guide rail of the column, and a driving unit configured to move the gripper on the guide rail. The gripper is provided with a plurality of coupling means for being engaged with the receiving means of the carrier.
The driving unit of lifting device is a pneumatic driving unit, an electrical drive unit or hydraulic driving unit.
In an embodiment, for each lifting device a control module is provided and configured to control the lifting device. Moreover, a central control unit is provided and configured to control the autonomous vehicle. The central control unit and the control module are configured to be able to communicate with each other.
Preferably, the central control unit is configured to control multiple autonomous vehicles. The central control unit controls the autonomous vehicle to move to different lifting devices. When it reaches the position closely to the lifting device, the central unit sends a signal to the control module of the corresponding lifting device such that the control module controls the lifting device to move the gripper.
Alternatively, the central control unit is configured not only to control the autonomous vehicles but also to control the lifting devices.
An embodiment of the present invention is directed to a manufacturing system comprising a plurality of machine tools and an automation device and the system for transporting the carrier. The lifting device is fixedly arranged in the proximity of the machine tool. The autonomous vehicle is applied to transport the workpiece, produced part, machining tools between the machine tools. The objects are first taken over by the gripper and further loaded into the machine tool by the automation device. The automation device can be a robot, an automatic tool changer, or an automatic pallet changer.
An embodiment of the present invention is related to a method for transporting a machining-related object by applying the transporting system of embodiments of the present invention. The method comprises the steps of: arranging the carrier on the lifting device; controlling the autonomous vehicle to move to the lifting device; and transferring the carrier having the machining-related object from the lifting device to the autonomous vehicle, in particular by moving the gripper in a manner such that the coupling elements are engaged with the receiving elements and the coupling means are disengaged with the receiving means.
In an embodiment, the gripper is controlled to move upwards such that the coupling elements are first at least partially engaged with the receiving elements and then the coupling means are disengaged with the receiving means.
Moreover, the method further comprises the steps of: controlling the autonomous vehicle having the carrier thereon to move to the lifting device; and transferring the carrier having the machining-related object from the autonomous vehicle to the lifting device, in particular by moving the gripper in a manner such that the coupling means are engaged with the receiving means and the coupling elements are disengaged with the receiving elements.
Preferably, the gripper is controlled to move downwards such that the coupling means are first engaged with the receiving means and then the coupling elements are disengaged with the receiving elements.
The carrier shown in
On the top surface 11 of the autonomous vehicle four coupling elements 20a, 20b, 20c and 20d are fixed. The number of the coupling elements and the position of the coupling elements are not limited as shown in the figures. More or fewer coupling elements than four (as shown in the figures) can be provided. In
The plate 50 comprise four holes 51a, 51b, 51c and 51d as receiving element and four bores 52a, 52b, 52c, 52d as receiving means. When the carrier is loaded on the autonomous vehicle, the coupling elements are engaged with the receiving elements. In particular, each cone enters into each hole. In further, the diameter of the hole is designed in a way that the carrier sits on the coupling element.
As shown in
While subject matter of the present disclosure has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. Any statement made herein characterizing the invention is also to be considered illustrative or exemplary and not restrictive as the invention is defined by the claims. It will be understood that changes and modifications may be made, by those of ordinary skill in the art, within the scope of the following claims, which may include any combination of features from different embodiments described above.
The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C.
| Number | Date | Country | Kind |
|---|---|---|---|
| 23184444.0 | Jul 2023 | EP | regional |
