The present invention relates to production lines, in particular production lines comprising:
at least one assembling station,
a chain conveyor device comprising a chain for transporting a plurality of pallets along said production line, wherein each pallet is provided for transporting parts to be assembled,
motor means for moving said chain,
an electronic control system,
said motor means and said electronic control system being configured for causing said chain-transported pallets to proceed with a continuous movement through said at least one assembling station.
In production lines of continuous moving type, parts or basic components are transported by pallets which proceed without stops along a conveyor line through a sequence of assembling stations, wherein further parts and components are sequentially assembled on the part or basic component carried by each pallet.
In production lines of the type indicated above, assembling operations are manually executed by operators, sometimes with the aid of automated systems. In this type of lines there is the need of improving the production efficiency and in particular of enabling the assembling operations which are to be executed by the operators to be as easy and fast as possible, while at the same time ensuring that the assembling operations are executed completely and correctly and with a high level of safety for the operators.
The main object of this invention is to satisfy the afore-mentioned requirements in the best possible manner
An equally important object of the invention is to provide a production line which ensures that the assembling status of the parts is constantly monitored and that the assembling operations are correctly executed.
A further object of the present invention is to provide a simple production line which can be easily integrated in any sections of the layout of a production environment.
A further object is to provide a production line adapted for assembling parts of different types and sizes.
A last but not less important object is to provide a production line which is ergonomic for the operators which interact with the automated systems of the line, so as to increase productivity and to ensure that the way of working of the operators be as least as possible affected by physical stress.
In view of achieving the above indicated objects, the invention is directed to a production line having all the features which have been indicated at the beginning of the present description and further characterized in that:
In a preferred embodiment, said command signal causes a stop of the chain conveyor device.
Preferably, an automatic system of assistance for the operator is associated to each assembling station, comprising a plurality of automated drawers provided for containing components to be used for assembling of said parts transported by the pallets.
Moreover, according to a further characteristic of the invention, a human machine interface is associated to each assembling station, said human machine interface is supported in a position which is accessible by the operator during the assembling operations.
In the afore-mentioned preferred embodiment, the rear hook unit comprises also a second interception element which, in the afore mentioned interception position of the rear hook unit, intercepts a second optical beam emitted by a second optical sensor, whose signal is used by the electronic control system for identifying the rear hook unit which is moved away from the pallet engaging position.
Furthermore, in this preferred embodiment, the implement used by the operator is carried by a slide which is freely slidably mounted along the transport direction of the pallets on a bearing structure mounted adjacent to said chain conveyor device, said implement having a structure including a sequence of elements which are movably mounted one relative to each other, according to different degrees of freedom, the last element of this sequence carrying a tool.
Thanks to the afore-mentioned features, the production line according to the invention achieves a series of important objects simultaneously. Firstly, the invention provides the immediate reporting of any obstacle or obstruction along the line and preferably also the immediate identification of the point of the conveyor chain in which a problem has occurred, thereby ensuring a correct operation of the line and safety for the operator.
During the execution of the manual assembly operations, the operator walks at the side of the line following a certain pallet in its continuous movement. During the execution of such operations, the operator uses the implement which is freely movable in a direction which is parallel to the line. The movement of the implement along the line is not motorized, and it is the operator himself who grips the implement and causes it to move in synchronism with the movement of the operator at the side of the pallet. All the afore-mentioned features render the way of working of the operator easy and efficient. The operator is further assisted by the system of automated drawers containing components to be used for assembling.
During the operations, the electronic control system recognizes at each instant the position of each pallet and of the implement used by the operator. This latter interacts with the control system by means of the human machine interface, which is supported at a position which is comfortably accessible by the operator during the assembly operations. In the preferred embodiment, the human machine interface is configured for example for indicating to the operator the correct sequence of operations to be completed on the basic parts; for confirming to the operator the correct execution of the executed individual operations (for example the tightening torque of a threaded connection); for receiving an input by the operator about the correct execution of an individual operation. Preferably the human machine interface is of the touch-screen type.
Further features and advantages of the invention will become apparent from the following description with reference to the annexed features, given purely by way of non limiting example, in which:
In the following description various specific details are illustrated, aimed to a better understanding of the embodiments. The embodiments can be implemented without one or more of the specific details, or with other methods, components, or materials, etc. In other cases, structures, materials or known-operations are not shown or described in detail in order to avoid that various aspects of the embodiment may become obscure.
The references herein used are only for convenience and therefore do not define the extent of the protection or the scope of the embodiments.
With reference to
The line 1 according to the invention further comprises a chain conveyor device 3 mounted adjacent to the assembling stations and provided for enabling transport of a plurality of pallets 5 along the line 1. Each pallet 5 is provided for example for carrying a basic part (such as a cylinder head) on which the operator O manually assembles further components.
In an actual embodiment of the production line according to the invention, the pallet 5 is provided in conformity to what is illustrated in the patent application EP15153558 of the same assignee.
As illustrated in the drawings and as previously indicated, at each of the afore-mentioned assembling stations 2 an operator O is dedicated which operates on the parts transported by the pallets 5 which continuously move in front of the operator. Each operator operates on all the pallets which pass through the assembling station 2 controlled by the operator. For each pallet which moves with continuous movement through the station, the operator executes all the required assembling operations on the transported part, while the operator moves at the side of the line in such a way as to follow the pallet during its movement. If all the manual operations are executed in a correct way and within a correct time, the basic part carried by the pallet has all the additional components correctly mounted thereon when the continuously moving pallet goes out from the afore-mentioned assembling station. If downstream of said assembling station at least one further assembling station is provided, a further operator is dedicated thereto, who executes further assembly operations, and the same is true for any additional stations downstream of the previous stations.
Again with reference to
Again with reference to
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As illustrated in
The implement 10 is carried by a slide 100 which is freely slidably mounted along the transport direction of the pallets 5 on a bearing structure 101 mounted adjacent to the chain conveyor device 3. The structure of the implement 10 is constituted by a sequence of elements which are movably mounted one relative to each other, according to different degrees of freedom. The last element of this sequence carries an electric wrench 105, which is used by the operator for tightening connection elements such as screws or nuts during the assembly cycle. Naturally, the wrench 105 constitutes only an example of a tool which can be used. Furthermore, preferably this wrench is connected so as to be removable from the structure which supports the wrench, in such a way as to be quickly replaceable by a tool of a different type. Finally, the wrench itself comprises a motorized spindle which preferably can be coupled with tools of different types.
In the embodiment illustrated herein, the slide 100 carries a support 100A on which, at a position which is vertically adjustable, a beam element 102 is mounted, which extends in a vertical direction. The top of the beam element 102 supports a plate 104A which is freely slidable along a direction which is horizontal and also perpendicular to the longitudinal direction of the line. In the illustrated example, the plate 104A supports a plate 104B which is freely slidable also in the same sliding direction of the plate 104A. The above described arrangement is modular, and it is possible to provide a single slidable plate or any number of slidable plates located in cascade one from each other.
Returning to the illustrated example, the plate 104B carries the wrench 105 in an manner adjustable around a vertical axis (see
Thanks also to the above indicated features of the implement 10, the production line 1 according to the invention ensures assembling operations which are easy and quick in such a way as to make the execution of the assembling operations efficient.
During the normal operation of the line 1, each operator O pushes or pulls the implement 10 along the bearing structure 101 which is adjacent to the dedicated assembling station 2, thereby following the pallet 5 transported by the chain conveyor device 3 and operating on the parts carried by the pallet 5. At the end of the passage of the pallet 5 along the individual station 2, the operator O pushes the tool in the opposite direction, for repeating the assembly operations on the next pallet 5 passing through the individual station 2.
Each assembling station comprises a plurality of data storing electronic control units (not shown) provided for recording the assembling operations completed on each pallet 5. The electronic units are in communication with the electronic control system 7. Thanks to these features, the production line 1 is adapted for a constant monitoring of the assembling status of the parts ensuring also the correct execution of the assembling operations which are carried-out.
As previously indicated, the chain conveyor device 3 comprises the endless chain 4, which is engaged around two toothed wheels 41, each mounted at the opposite ends of the chain conveyor device 3. The closed loop chain 4 has an upper active chain run and a lower passive chain run. The upper chain run is active and covered by a set of plates 42, which are fixed relative to the chain 4 moved by the motor means 6.
With reference to
In particular with reference to
Also each of the rear hook unit 9 comprises a support bracket 91 rigidly connected to the chain 4 and a hook 92 which is pivotally mounted on the support bracket 91 around an axis which is transverse to the longitudinal direction of the chain 4. Each rear hook unit 9 comprises also a spring 93 which biases the hook 92 towards an engaging position of the individual pallet 5 (shown in
In
As illustrated in
The chain conveyor device 3, as illustrated in
Both the sensors are in communication with an electronic unit E which is connected to, or incorporated in, the electronic control system 7 of the line 1.
With reference in particular to
The electronic control system 7 of the line 1 is programmed for generating a command signal when the first optical beam 11 of the first optical sensor 12 is intercepted by the first interception element 94 of one of the rear hook units 9. This command signal can be used to generate a visual and/or acoustic alarm signal, but more preferably it causes also, or only, a stop of the chain conveyor device 3.
Thanks to this feature, the production line according to the present invention provides adequate safety to the operators that interact with the production line. Furthermore when the optical beam emitted by the second optical sensor is intercepted by the second interception element 95, the electronic unit E of the line 1 is programmed for emitting a signal which is used by the control electronic system 7 for identifying the hook 92 which moves away from its engaging position. The electronic system 7 is thus configured for identifying on which pallet 5 a malfunction is caused by the presence of an obstacle preventing the movement of the specific pallet 5.
The electronic control system 7 of the line 1 comprises also an encoder (not illustrated) provided for controlling the position of the chain 4, and thus of the pallet 5 which is moving through the assembling station, and a second encoder (not illustrated) provided for the position control of each implement 10 along the bearing structure 101.
Thanks to the above features, the production line 1, with the continuously moving pallets 5, ensures quick and easy assembling operations, while being also adapted for checking proper execution of each cycle of assembling operations and ensuring a prompt intervention in case of any malfunction, in particular in the case of any obstacle or obstruction preventing movement of the pallets.
Furthermore, the production line 1 according to the invention provides highly ergonomic operations for the operators 9 and enables parts of different sizes to be assembled, while monitoring continuously the assembling status and thus the production level of the line 1.
The number of the assembling stations of the line 1 is variable according to the production requirements and according to the parts to be assembled which are transported by the pallets 5. Also thanks to this feature, the production line according to the invention results to be easy to be integrated in different sections of the layout of a production environment.
Naturally, while the principle of the invention remains the same, the details of construction and the embodiments may widely vary with respect to what has been described and illustrated purely by way of example, without departing from the scope of the present invention.
Number | Date | Country | Kind |
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16168061.6 | May 2016 | EP | regional |