GB1567587A

GB1567587A - Workpiece transfer mechanisms

Info

Publication number: GB1567587A
Application number: GB5206877A
Authority: GB
Original assignee: Micafil AG
Current assignee: Micafil AG
Priority date: 1976-12-15
Filing date: 1977-12-14
Publication date: 1980-05-21
Also published as: CH597059A5; IT1079209B; FR2374135B1; DD133935A5; FR2374135A1; DE2719229A1; DE7713605U1

Description

(54) IMPROVEMENTS IN OR RELATING TO WORKPIECE TRANSFER MECHANISMS (71) We, MICAFIL AG, a Swiss Corporate Body of Badenerstrasse 780, 8048 Zurich, Switzerland do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention relates to a workpiece transfer mechanism for supplying workpieces to and removing them from machmes which perform operations upon them.

The invention is especially applicable to machines for performing operations on armatures of electrical machines and having two or more stations operating in parallel.

In manufacturing machines, especially machines for performing operations on armatures for electrical machines, having two or more operating stations operating in parallel there are employed synchronized feeding systems and removal systems for supplying work-pieces to and removing them from the operating stations.

The known synchronized systems, which are always adjusted to the slowest machine and in which when one machine is idle the other machines operating in parallel cannot be supplied, do not as a rule allow efficient working.

In contrast, in time-controlled systems the individual timing of each operating station is followed, so that if one station ceases to function the remainder continue to be fed without interruption. Belt conveyors and linked conveyor belts are known with which transport of the armatures, for example unwound armatures, is effected in the direction of the armature axis without any change of attitude. This results in disadvantages, however, since transfer mechanisms can only be employed to a limited extent and on stacking of the axially aligned armatures there is a risk of mutual hooking together of the armatures.

It has already been proposed to employ inclined paths with pivotally movable escapement means, along which the armatures, transported in a direction perpendicular to their axes, move by rolling on their outer shaft ends. These transfer devices cannot be used for armatures of different shaft end diameters because, among other reasons, differences in level in the course of the operations must be overcome. A further substantial disadvantage is that these devices are expensive to construct.

Armature manufacturing machines are also known in which the armatures are transported by themselves rolling along inclined rollways perpendicular to the armature axis. The armatures must first be raised to the necessary height in order to pass by way of a mechanical switching system and further rollways to, for example, three winding machines arranged in parallel.

These known paths cannot be used for all kinds of armatures, since guiding of the armatures is difficult and over long path lengths may lead to hooking-together of and damage to the armatures. In addition, in this system also the differences in level must be dealt with, so that additional causes of damage may result.

It is the object of the present invention to provide a transfer mechanism which does not exhibit the defects of the known transfer arrangements, that is adaptable to the operational requirements of paralleled operating stations and which is readily capable of being variably integrated with automatic armature assembling machines.

According to the present invention there is provided a workpiece transfer mechanism for the supply of workpieces to at least two machines, which machines operate independently each of the other or others to perform the same working operations on workpieces supplied to them, wherein there are provided adjacent one another a first conveyor for supplying workpieces to the machines and a second conveyor for removing workpieces from the machines, each of the conveyors being constituted by a plurality of separate endless and individually driven conveyor sections and workpiece transfer devices being provided between adjacent conveyor sections in each of the first and second conveyors, as well as an insertion and removal mechanism for each machine, each said insertion and removal mechanism being arranged to convey workpiece from one conveyor section of the first conveyor to the associated machine and from that machine to one conveyor section of the second conveyor.

As compared with arrangements of the same operational capabilities, the advantage of the invention is that the individual components of the transfer mechanism, consisting of several endless conveyor sections, coupled with workpiece transfer, supply and removal arrangements can be variably combined into transfer units of any required size according to need, when supplying parallelled operating stations (i.e.

stations having machines operating independently of each other to perform the same operations on workpieces supplied to them), so that even when alterations of armature form are made the capacity of the parallelled stations may be easily and rapidly adapted to the new conditions.

It is especially advantageous if a storage position is provided at the end of each section of the first conveyor and a delivery position at the beginning of each section of the second conveyor.

Since, as a result of this arrangement, on the one hand the storage positions of the first conveyor are always occupied by workpieces and further workpieces are always moving into these positions, and on the other hand the withdrawal positions are kept free of workpieces and the workpieces are immediately transported away from these positions, additional idle periods of the parallelled operating stations are avoided.

It is also advantageous that an individual position empty of any workpiece is provided in each section of the path of the second conveyor.

These measures may be adopted for optimising the progress of manufacture when the parallelled operating stations operate with a very short time period.

In a preferred embodiment, priority control means are provided for the first and the second conveyor. Correctly timed performance of the operations performed by the parallelled operating stations is thus ensured.

An embodiment of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a schematic perspective diagram representing an apparatus in accordance with the invention; Figure 2 is a longitudinal section of a workpiece transfer device between two conveyor sections of Figure 1; and Figure 3 is a cross-section of a mechanism for supplying workpieces to and removing them from an operating position, taken along section line III-III of Figure 2.

In Figure 1, reference numeral 1 denotes a transfer mechanism which is provided for the purpose of loading and unloading three parallelled operating stations 2a, 2b, 2c, specifically winding stations, with additional transfer by means of a capstan device 8 having four similar arms and arranged for rotation in a horizontal plane arranged in the vicinity of each of the parallel winding stations 2a, 2b, 2c. The transfer mechanism consists of adjacently disposed first and second conveyor paths I and II, conveyor path I being arranged for the supply of unwound armatures 6' and conveyor path II for the removal of wound armatures 6". Each of the conveyor paths I, II is formed of a plurality of path sections, such as 3, 3' which are endless and are individually driven, the sections being coupled together by armature transfer devices indicated at 4. The path sections 3, 3' of the conveyor paths I, II are arranged in pairs so as to cooperate with the respective supply and removal devices 5a, 5b, 5c. While the operation performed at an operating station is proceeding the supply and removal devices 5a, 5b, Sc are in their waiting positions A'a, A'b, A'c, each of which is located above the respective waiting position Aa, Ab, Ac of conveyor Path I for supplying the workpieces. In order to ensure properly timed operation of the operating stations, priority control means are provided for controlling the movement of the armatures to and from the parallelled operating stations. To ensure properly timed advance or removal of the armatures further control means 7, advantageously proximity switches, are provided at the beginning and end position of each path section 3 and 3'.

The reference numbers used in Figure 1 are applied also to the same parts in Figures 2 and 3. The known priority switching circuits, which contain predominantly relays as switching elements to carry out the switching logic, may be self-contained or may be provided as a part of a computer controlling the actual operating program.

In Figure 2 the conveyor for supplying armatures 6' is designated by I, parts of two path sections 3 being shown in partial cross-section. These path sections are coupled together by a workpiece transfer mechanism 4. The workpiece transfer mechanism 4 secured to the path sections 3a, 3b a constructional support S includes a pneumatic cylinder 9 provided with a forked lifting member 10 for lifting the armatures 6' from and lowering them into the angular notches 13' of the workpiece carriers 13. Cylinder 9 is carried on a pivoted arm actuated by a further pneumatic cylinder 9, for transferring the armature 6' from the waiting position Aa of the leading path section 3a to the initial position of the trailing path section 3b by means of the workpiece transfer device 4. The supply and removal device 5a is, in its waiting position, situated above the waiting position Aa of the path section 3, while the unwound armature 6' is removed from the workpiece carrier 13 of conveyor I by a gripping means 11, arranged for vertical displacement, in order subsequently to be conveyed to the capstan device 8.

Figure 3 shows, in cross-section along the section line III-III in Figure 2, the two adjacent path sections 3, 3' of the conveyors I, II, with the workpiece transfer device 4. The supply and removal device Sa includes a vertically displaceable gripping means 11 and is arranged to be movable horizontally along a guide 12 from its waiting position A'a above the conveyor I to the casptan device 8, back to the receiving position Ba of conveyor II and then further back to its waiting position A'a, that is, its initial position. Between the supply and removal mechanism Sa and the associated processing station 2a (of which the position only is indicated by the arrowed line), there is provided in this embodiment a capstan device 8; if preferred, the supply and removal device may be in direct connection with the operating station 2a.

The manner of operation of the transfer device described above with reference to Figures 1 to 3 is as follows: Each of the parallelled operating stations 2a, 2b, 2c performing the same operation may for example be a winding station for winding armatures 6', to which each armature 6' is transferred individually by way of the capstan device 8 arranged for properly timed stepwise horizontal rotation through 90" at each step, of which one is provided at each of the winding stations 2a, 2b, 2c. From a supply station (not illustrated) or from an operating station performing a preceding operation, for example, an automatic commutator pressing-on mechanism, the unwound armature 6' pass to the transfer mechanism 1. The unwound armature 6' can, if necessary, be taken alternatively from a movable store by means of the armature transfer device 4 and deposited in the notches 13' of the first workpiece carrier 13 of the conveyor I in the region of the winding stations 2a, 2b, 2c. Parallel to conveyor I there is provided a further conveyor II for carrying away the wound armatures 6". Transport of the armatures on the individual conveyor sections 3, 3' is effected without any kind of fastening mechanism for gripping and releasing the individual armatures. Conveyors in which the individual path sections 3, 3' each consist of two parallel, endless roller chains and on which there are provided for the horizontal transport of the armatures a plurality of workpiece carriers 13 which consist for example of support members with angular recesses 13' placed at equal distances from one another, are particularly suitable. The path sections 3 of conveyor I advance unwound armatures 6 laid in the workpiece carriers 13, up to the final position Ac of the last path section 3. The unwound armatures 6' laid in the workpiece carriers 13 of the final positions Aa, Ab, Ac of the path sections 3 of the conveyor I are likewise situated in the waiting position for subsequent winding or for further advance, all the workpiece carriers 13 situated in the conveyor path I being occupied by unwound armatures 6'. As soon as the waiting position and the subsequent initial position in the succeeding path section 3 are occupied by armatures 6', the transfer device 4 is inhibited until the initial position is again emptied by advancing movement of the armatures. On the other hand the discharge positions Ba, Bb, Bc of the conveyor II for removal of the wound armatures 6" are controlled so that no armatures are situated in the workpiece carriers 13 in these positions of the path sections 3', or if present, are removed as rapidly as possible in order to empty these positions once again. As soon as one or more of the wound armatures 6" are placed by the gripping means 11 of the insertion and removal mechanisms 5a, Sb, Sc into the workpiece carriers at the corresponding removal positions Ba, Bb, Bc, a properly timed step-by-step onward transport of the subsequently wound armatures is initiated, until all the discharge positions Ba, Bb, Bc are again emptied of armatures. In cases where the cycle time of the parallelled operating stations is very short, the final position Ca, Cb, Cc of each path section 3' of conveyor II may in a similar manner be kept empty of wound armatures, so that properly timed operation of the operating stations is ensured even with very short cycle times.

In these cases the first and last positions of each path section 3' are kept free of armatures 6", as is shown in Figure 1, and as soon as an armature is advanced into the last position Ca, Cb, Cc of a path sec tion 3', the armature is transferred by the appropriate transfer device 4 to the subsequent path section 3'. For this correctly timed armature transport, that is the advance and transfer of the armatures 6, control elements 7, preferably proximity switches, are provided at the first and last positions of each path section 3, 3' of the two conveyors I, II. To deal with the case where an unwound armature 6' should be transferred simultaneously to the winding station by means of the loading and unloading device Sa, Sb, Sc and transferred to the next path section 3 by the transfer device 4, additional control means for priority control are provided, by means of which armatures are first of all passed to the winding stations 2a, 2b, 2c and only afterwards is the filling-up of the conveyor I ensured. A similar priority control is provided for conveyor II for the removal of the wound armatures 6", when on the one hand the wound armature 6" is to be placed in the receptacle of a workpiece carrier 13 at the discharge position Bb, Bc by the insertion and removal device Sa, Sb, Sc and on the other hand wound armatures 6' are to be advanced from the respective end positions Ca, Cb, Cc of the previous path sections 3' by the transfer devices 4 into the discharge positions Bb, Bc. In such a case the removal of the armature 6" through the respective insertion and removal device Sa, 5b, Sc into the receptacle 13' of the workpiece carrier 13 of path section 3' is ensured. Properly timed operation of the parallelled winding stations is thus ensured. As soon as one or more insertion and removal devices Sa, Sb, Sc leave their initial waiting positions A'a, A'b, A'c the respective appropriate priority control is initiated.

The operation of the transfer apparatus as described above could advantageously be controlled by means of a computer (not shown) at the same time as the actual operation of the parallelled operating stations.

The invention is obviously not limited to what is shown in the drawings. Thus the winding stations could be replaced by other operating stations performing different operations, such as for example two or more parallelled armature impregnating stations.

In Figures 1 to 3 the transfer mechanism of the invention is illustrated as used in the manufacture of armatures for electrical machines. In modifications, the transfer mechanism could also be made use of for other types of workpiece. This would require merely an adaptation of the workpiece carriers, and if necessary also the workpiece transfer devices.

WHAT WE CLAIM IS: 1. A workpiece transfer mechanism for the supply of workpieces to at least two machines, which machines operate independently each of the other or others to perform the same working operations on workpieces supplied to them, wherein there are provided adjacent one another a first conveyor for supplying workpieces to the machines and a second conveyor for removing workpieces from the machines, each of the conveyors being constituted by a plurality of separate endless and individually driven conveyor sections and workpiece transfer devices being provided between adjacent conveyor sections in each of the first and second conveyors, as well as an insertion and removal mechanism for each machine, each said insertion and removal mechanism being arranged to convey workpieces from one conveyor section of the first conveyor to the associated machine and from that machine to one conveyor section of the second conveyor.

2. A workpiece transfer mechanism in accordance with claim 1 wherein a waiting position is established at the end of each section of the first conveyor and a removal position at the beginning of each section of the second conveyor.

3. A workpiece transfer mechanism in accordance with claim 2 wherein it is arranged that a position empty of any workpiece is provided at the end of each section of the second conveyor.

4. A workpiece transfer mechanism in accordance with any one of claims 1 to 3 and including a priority control means for ensuring that movement of a workpiece between a conveyor and a machine takes precedence over movement of a workpiece from one conveyor section to another.

5. A workpiece transfer mechanism substantially as described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. tion 3', the armature is transferred by the appropriate transfer device 4 to the subsequent path section 3'. For this correctly timed armature transport, that is the advance and transfer of the armatures 6, control elements 7, preferably proximity switches, are provided at the first and last positions of each path section 3, 3' of the two conveyors I, II. To deal with the case where an unwound armature 6' should be transferred simultaneously to the winding station by means of the loading and unloading device Sa, Sb, Sc and transferred to the next path section 3 by the transfer device 4, additional control means for priority control are provided, by means of which armatures are first of all passed to the winding stations 2a, 2b, 2c and only afterwards is the filling-up of the conveyor I ensured. A similar priority control is provided for conveyor II for the removal of the wound armatures 6", when on the one hand the wound armature 6" is to be placed in the receptacle of a workpiece carrier 13 at the discharge position Bb, Bc by the insertion and removal device Sa, Sb, Sc and on the other hand wound armatures 6' are to be advanced from the respective end positions Ca, Cb, Cc of the previous path sections 3' by the transfer devices 4 into the discharge positions Bb, Bc. In such a case the removal of the armature 6" through the respective insertion and removal device Sa, 5b, Sc into the receptacle 13' of the workpiece carrier 13 of path section 3' is ensured. Properly timed operation of the parallelled winding stations is thus ensured. As soon as one or more insertion and removal devices Sa, Sb, Sc leave their initial waiting positions A'a, A'b, A'c the respective appropriate priority control is initiated. The operation of the transfer apparatus as described above could advantageously be controlled by means of a computer (not shown) at the same time as the actual operation of the parallelled operating stations. The invention is obviously not limited to what is shown in the drawings. Thus the winding stations could be replaced by other operating stations performing different operations, such as for example two or more parallelled armature impregnating stations. In Figures 1 to 3 the transfer mechanism of the invention is illustrated as used in the manufacture of armatures for electrical machines. In modifications, the transfer mechanism could also be made use of for other types of workpiece. This would require merely an adaptation of the workpiece carriers, and if necessary also the workpiece transfer devices. WHAT WE CLAIM IS:

1. A workpiece transfer mechanism for the supply of workpieces to at least two machines, which machines operate independently each of the other or others to perform the same working operations on workpieces supplied to them, wherein there are provided adjacent one another a first conveyor for supplying workpieces to the machines and a second conveyor for removing workpieces from the machines, each of the conveyors being constituted by a plurality of separate endless and individually driven conveyor sections and workpiece transfer devices being provided between adjacent conveyor sections in each of the first and second conveyors, as well as an insertion and removal mechanism for each machine, each said insertion and removal mechanism being arranged to convey workpieces from one conveyor section of the first conveyor to the associated machine and from that machine to one conveyor section of the second conveyor.