DE8811524U1 - Device for providing and/or removing workpieces - Google Patents

Description

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The invention relates to a device for providing and/or removing workpieces at a workstation according to the preamble of claim 1.

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that work can continue for a certain period of time independently of other workplaces. This means that a supply of workpieces to be processed must be stored in the same way as a supply of processed workpieces which cannot yet be received by the next workplaces. These small interim storage facilities are often simply created by stacking boxes with unprocessed and processed workpieces at the workplace. However, these boxes then often have to be moved. In the case of heavy boxes in particular, the person working at the workplace is often unable to do this on their own, so they need the help of a forklift truck .

becomes dependent.

Furthermore, devices for providing and/or removing workpieces are already known, which, for example, have roller conveyors leading to and from the work station, on which the containers containing the workpieces run. Such devices require a relatively large amount of space when the conveyors are in the same horizontal plane. This horizontal arrangement would in itself be advantageous in terms of the force required to move a container from one roller conveyor to the other. If the two roller conveyors are arranged one above the other, which saves space, a lifting device is required at least on the work station side in order to move a container from the lower

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Roller conveyor to the upper roller conveyor« This means that these devices have a mechanically complex structure overall. In addition, the lifting device requires additional space, especially at the workplace, and hinders work.

The present invention therefore aims to create a device according to the preamble of claim 1, which, with a mechanically simple design, enables ergonomically favorable removal and delivery of workpieces at the workplace, achieves the desired buffering and enables the removal and feeding of workpieces without disruption at the workplace.

This task is solved according to the invention by a device according to claim 1.

With the device according to the invention, two containers with workpieces can be removed at the same time from the vertical first transfer run of the endless conveyor with a forklift or another transport vehicle and two new containers with workpieces to be processed can be placed on top. This means that the forklift is only required at longer intervals. Since the two places on the vertical run are one above the other, the forklift has comparable access to both ^places . In addition, the first transfer run requires only a small amount of space. At the lower end of the second transfer run, however, another workpiece container is ergonomically convenient and freely accessible. The pallets are moved through the different waiting places on the triangular conveyor by a single endless conveyor that is mechanically simple to implement.

Advantageous developments of the invention are set out below.

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sayings given.

With the development of the invention according to claim 2 it is achieved that the pallets on the conveyor path are automatically aligned by the effect of gravity, so that no special measures need to be taken to secure the workpieces in containers carried by the pallets or to forcibly align the pallets.

The further development of the invention according to claim 3 is advantageous in view of the smallness of the tipping moments on the fastening points of the pallets on the end load conveyor.

In a device according to claim 4, the further movement of a pallet from one strand to the next strand of the endless conveyor takes place particularly quickly due to the lever formed by the support arms at a given running speed of the endless conveyor. The pallet thus clears the way for the next pallet particularly quickly at the strand joints.

The development of the invention according to claim 5 is advantageous in terms of a particularly simple removal of workpieces at the workplace or a particularly simple loading of workpieces at the workplace.

With a device according to claim 6, there is good access to the interior of containers carried by the pallets, which contain or are intended to hold the workpieces*, even if these containers have high walls. The inclined position of the containers at the workstation makes it easier to remove and insert the workpieces under visual control.

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The development of the invention according to claim 7 enables such tilting of containers containing workpieces at the workplace using particularly simple mechanical means which can easily generate the forces required to tilt heavy containers.

With a device according to claim 8, the slanting of the pallets at the workstation can be carried out particularly carefully.

20

The development of the invention according to claim 9 provides the advantage that the endless conveyor device can also be operated against the normal direction of rotation.

The development of the invention according to claim 10 results in a particularly low construction height of the device due to the early inclination of the pallets already at the lower end of the first transfer run

In all of the above-mentioned developments, the force for tilting the containers is provided by the motor of the endless conveyor device.

A device according to claim 11 has a particularly small space requirement.

30

The development of the invention according to claim 12 is advantageous with regard to conveying very heavy pallets using a mechanically simple endless conveyor device.

In a device according to claim 13, the weight forces of the pallets are transferred to the endless conveyor device without any tipping moment.

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With the development of the invention according to claim 14 it is achieved that the endless conveyor device does not bang
can be set as long as workpieces are being removed or inserted at the workstation or as long as containers containing conveyed items are being removed or placed at the first transfer run by a conveyor vehicle.

The development of the invention according to claim 15 is in
Hii-ölick on an exact specification of the conveying paths in the
transfer area and with a view to avoiding a
Swinging of the pallets is an advantage.

The development of the invention according to claim 16
serves to guide the pallets vibration-free on the specified conveyor path.

With the development of the invention according to claim 17 it is achieved that the pallets and the endless conveyor device are not damaged by improper approach of a baby stacker or the like against the first transfer run.
can be.

The invention is explained in more detail below using exemplary embodiments with reference to the drawing. In this drawing:

Figure 1: a side schematic view of a transport machine for bringing assembly parts to a work station;

Figure 2: a top view of the transport machine shown in Figure 1;

Figure 3: a block diagram of a safety device

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for use in the transport machine according to Figures 1 and 2|

4: a detail of the suspension of pallets on an endless conveyor of the transport machine according to the

Figures 1 and 2;

Figure 5: a view similar to Figure 1, but showing a modified transport machine; and

Figure 6: a view similar to Figure 1 of a further modified transport machine.

Figure 1 shows an automatic transport machine for feeding an assembly station with workpieces ₃ to be assembled, whereby the work station is on the left in Figure 1 and at the bottom in Figure 2 and the intermittent feeding of larger quantities of workpieces takes place from the right in Figure 1 and from the top in Figure 2.

The transport machine has a frame standing on the floor of the production hall with front vertical supports 10 and rear vertical supports 12. These vertical supports are connected by side walls 14, an upper front wall 16, a bent lower front wall 18, a ceiling wall 20 and rear cross braces 22, 24.

Two pairs of deflection wheels 26, 28 and 30, 32 are mounted in the rear vertical supports. Two universal wheels 34, 36 are mounted in the front supports 10. As can be seen from Figure 1, the position and distance between the axes of the deflection wheels is selected so that these axes form half of an equilateral triangle, the height of this triangle being given by the connection of the axes of the deflection wheels 26, 30, half the base side of the

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is given by the connection of the ⁴ axes of the steering wheels 30j 34 and the leg of the equilateral triangle rising below 60* to the horizontal is given by the connection of the axes of the universal steering wheels 34 and 26.

The deflection wheels 30, 32 are firmly coupled to one another, e.g. by a schematically indicated shaft 39, which is connected to a drive motor shown at 40 in Figure 3.

A first roller chain 42 runs over the deflection wheels 26, 30, 34, and a second roller chain 44 runs over the deflection wheels 28, 32, 36. Four pairs of support arms 46 are attached to the roller chains 42, 44 at equal distances, one after the other, using two support bolts 48*50. The support arms 46 in turn pivotably accommodate a hinge bolt 52, which is attached to the upper end of a V-shaped support bracket 54. Two such support brackets 54, together with a base plate 56 and a rear wall SB, form a rigid gondola, designated 60 overall, onto which large containers 62 can be placed, which contain workpieces to be assembled. At the joint between the base plate 56 and the rear wall 58, the gondolas 60 have small wheels 64.

As can be seen from Figure 1, the roller chains 42, 44 run on a substantially triangular conveyor path, which according to the axis arrangement of the deflection wheels 26 to 36 corresponds to half of an isosceles triangle. The three strands of the roller chains 42, 44 are a vertical transfer strand 66, a horizontal connecting strand 78 and a diagonally rising second transfer strand 70.

Figure 1 shows the state of the transport machine that it is normally in when working. Two receipts—

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The gondolas 60-1 and 60-2 are in the overhead conveyor 70 of the chain conveyor, the gondola 60-3 is at the workplace and is pushed out of the vertical alignment by the fact that when it ran into the waiting area its wheels 64 ran against tilting wheels 72 fixed to the frame. In this way the interior of the container 62-3 carried by the gondola 60-3 is particularly easily accessible to the person working at the workplace through an opening 74 which is limited by the front walls 16 and 18. The gondola 60-4 is in the upper half of the sloping overhead conveyor 70 and is far enough away from the gondola 60-3 in the horizontal direction that it completely clears access to the upper end of the container 62-3.

A forklift truck shown at 76 in Figure 2 can thus remove both containers 62-1 and 62-2 at the same time and replace them with full containers while workpieces are being assembled at the workplace. The cross braces 22, 24 also prevent the forklift truck from driving too far into the automatic transport system and damaging the conveyor device in the process.

A light curtain 78 is provided at the opening 74, which is obtained by reflecting a light beam in a zigzag pattern between two reflector rails 90, 92. The light beam is emitted by a light source 84 and falls on a detector 96 when the opening 74 is open. Similarly, a light curtain 88 is provided at the rear of the transport machine, which is obtained by reflecting a light beam back and forth between reflector rails 90, 92. The light beam comes from a light source 94 and falls on a detector 96 when the rear of the transport machine is open.

As can be seen from Figure 3, the output signals

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of the detectors 86 and 96 by an AND-Blled 98 together

Another AND gate 100 receives the output signals from two buttons 102, 104, which are part of a two-hand safety device for the automatic transport system. A third AND gate 106 combines the output signals from the AND gates 98, 100. Its output signal is used to control a control circuit 108, which is assigned to the drive motor 4ö. This means that the automatic transport system can only be started if there is no obstacle in the path of the gondolas 96 on either the front or the back, and if the gondolas 60 are moved to the next waiting place by pressing both buttons 102, 104. If the containers 62-1 and 62-2 have both been replaced by full containers by the forklift truck 76, the person working at the workstation can request two more filled containers after emptying the container 62-3 standing there. Then two empty containers are again placed in the vertical transfer section 66 of the endless conveyor and are replaced by full containers using the forklift truck 76.

Although the transport machine was described above with reference to an assembly station where workpieces are only used, it is understood that this transport machine can equally be used at a work station to carry away workpieces produced there. In this case, the forklift truck 76 always removes full containers in the transfer run 66 and replaces them with empty containers.

The transport machine can also be used for both purposes at the same time. In this case, the waiting area "4 ¹ in the upper part of the rising transfer run 70 is given priority.

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The container 62-4 is also assigned an additional tilting device (see Fig. 5), e.g. a hydraulic working cylinder (Fig. 5), the piston rod of which carries a wheel 112 that can be moved against the rear wall 58 of the gondola 60. The working cylinder 110 is synchronized to the cycle of the endless conveyor by a control system not shown in detail here in such a way that it tilts the gondola 60-4 after it has entered the waiting area "4" in a similar way to how the gondola 60-3 is tilted by the tilting wheels 72. The container 62-4 is now easily accessible for a »sound operator« with the opening 74 enlarged accordingly, and workpieces can be removed from the container 62-3 at the workplace and placed in the container 62-4 after the work has been carried out.

As an alternative to the variant just described, one can also use an eccentric disk synchronized with the clock movement of the endless conveyor, which works with the underside of the base plate 56 of the gondola 60-3, or a tilting wheel 114, which works together with an extension 116 of the support bracket 54, for example, as indicated by dashed lines in Figure 5.

The embodiment according to Figure 5 also shows a further variant to that according to Figure 1, in which the gondolas 60 do not hang over support arms 46 but directly on the roller chains 42, 44. This keeps the roller chains 42, 44 away from tipping moments. In order to ensure the same conveying path, _which ensures that the gondolas 60 pass each other on their triangular conveying path, the diameter of the deflection wheels 26 to 36 is increased by the effective length of the support arms 46. This variant is also shown in dashed lines.

As can be seen from Figure 4, the roller chains 42, 44 run supported by support rails located behind them

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118. By attaching the support arms 46 to the two spaced support beams 48, 50, it is ensured that the support arms 46 are essentially perpendicular to the roller chains. In order to exclude even small vibrations of the belts 60, several guide bolts 120 can be provided on the support arms 46, which are arranged one after the other in the direction of movement and which engage with ample running clearance between the legs of a U-shaped guide rail 122, which extends along the conveying path of the roller chains 42, 44.

10 extends.

In the transport machine according to Figure 6, the tilting wheel 72 is replaced by a hyperbolic-like curved tilting rail, designated as 124. Its circular apex connects a rail section 126 rising slightly to the right in Figure 6 with a rail section 128 rising to the top left at 45*. This extends so far that it is safely gripped by the running wheels 64 if the drive motor 40 runs against the normal running direction intentionally or due to faulty control. In this way, the gondolas 60 in Figure 6 can also rotate in an anti-clockwise direction without danger.

A ramp section 130 is formed on the rail section 126 and runs back to the ground. This causes the gondolas 60 to be inclined in the first section of the connecting strand 68.

In addition, the deflection roller 34 is placed even lower, which further facilitates the removal of workpieces from the container 62-3. The triangle which is defined by the axes of the deflection wheels 26» 30 and 34» therefore has an obtuse angle at the axis of the deflection wheel 30.

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Claims (1)

* · β · a ti·· 2494.2 ·"· · &mdash;4 &mdash; ·· " 09.09.19SS Expectations 1. Device for providing and/or removing OS workpieces at a workstation, with a plurality of pallets, which can carry, for example, containers holding markings, with a first transfer station - for pallets, which is remote from the workstation, with a second transfer station for pallets adjacent to the workstation, and with a transport device for moving the pallets between the two transfer stations, characterized in that the transport device has an endless conveyor device (22 to 44) which carries at least four pallets (60) one after the other at regular intervals and has the following strands: a first transfer strand (66) forming the first transfer station and receiving at least two pallets (60-1, 60-2), a second transfer strand (68) for the second transfer station. station forming-3 diagonally rising second transfer run (70), which leads to the upper end of the first transfer run (66), as well as a connecting run (68) leading from the lower end of the first transfer run (66) to the lower end of the second transfer run (70). 2. Device according to claim 1, characterized in that the pallets (60) are supported by the endless conveyor device (26 to 44) so as to be pivotable about a horizontal axis (32). 3. Device according to claim 2, characterized in that the pivot axes (52) lie in the conveying surface of the endless conveyor device (26 to 44). 4. Device according to claim 2, characterized in that the pivot axes (52) are attached to the final release conveyor device (3!6 to 44) via support arms (46). 2494.2 09-09.1988 tr 5. Device according to one of claims 1 to 4, characterized characterized in that the angle of attack of the second transfer run (70) is selected such that unhindered access from above to a pallet (60-3) located at the lower end of the second transfer run (70) is provided past a pallet (60-4) located in an upper section of the second transfer run (70). 6. Device according to one of claims 2 to 5, characterized by means (72, 124) for inclining the pallet (60-3) located at the lower end of the second transfer run (70). 7. Device according to claim 6, characterized in ua8 the tilting means comprise at least one tilting wheel (72) which cooperates with a lower section of the pallets (60) when they reach the end of the connecting strand (68). 20 8. Device according to claim 6, characterized in that the tilting means comprise at least one tilting rail (124) which cooperates with a lower section of the pallets (60) when they pass through the connecting section (70). 9. Device according to claim 5, characterized in that the tilting rail (124) has a ramp-shaped rising rail section (126) which reaches under the outermost end of the pallet track. 10. Device according to claim 8 or 9, characterized in that the tilting rail (124) has a ramp-shaped rail section (128) adjacent to the first transfer run (66). UM I « »I ·· I t &bull; i .· It»
I » &bull; I · I 2494*2 09.09- ?9 ii. Device according to one of claims 1 to 4, characterized in that the conveying path of the endless conveyor device (26 to 44) has the shape of half an equilateral triangle, the first transfer run (66) forming the contour line of the triangle, the connecting run (68) forming half the base side of the triangle and the second transfer run (70) forming an obliquely rising leg of the triangle. 12* Device according to one of claims i to 11, characterized characterized in that the endless conveyor device has two coupled (38) endless conveyors (26, 30, 34, 42 or 28, 32, 36, 44) arranged on both sides of the conveyor path, each of which carries one side of the pallet (60). 13. Device according to one of claims 1 to 12, characterized in that at least one driven deflection wheel (30, 32) of the endless conveyor device (22 to 44), ^preferably all deflection wheels (26 to 36) have a diameter which is larger than the width of the pallets (60). 14. Device according to one of claims 1 to 13, characterized by the transfer strand (66, 70) associated monitoring sensors (73 to 98) and by a control circuit (108) for a drive motor (40) of the endless conveyor device (26 to 44), which operates depending on the output signals of the monitoring sensors (78 to 96) combined via an AND gate (98). 15. Device according to one of claims 1 to 14, wherein the endless conveyor device has conveyor chains, characterized in that the conveyor chains are roller chains (42, 44) and run on support rails (118) at least in the transfer strands (66, 70). 2494*2 « * Uli 11
&igr; 16. Device according to one of claims 1 to 15, the pallets (60) hang on the lifting device (26 to 44) via support arms (46), characterized in that the support arms (46) have at least two spaced guide pins (120) which run in a guide rail (122). 17i Device according to one of claims 1 to 16 _S, characterized by stop rails (22, 24) for the fork of a forklift truck (76) assigned to the places in the first transfer run (66).