EP1261538A1

EP1261538A1 - Conveyor device for transporting and expelling material to be conveyed

Info

Publication number: EP1261538A1
Application number: EP01915086A
Authority: EP
Inventors: Rolf Wiehler
Original assignee: Siemens Production and Logistics Systems AG
Current assignee: Siemens AG
Priority date: 2000-03-09
Filing date: 2001-03-06
Publication date: 2002-12-04
Also published as: WO2001066446A1; US20030019719A1; US6776277B2; JP2004517708A

Abstract

The invention relates to a conveyor device for transporting and expelling material to be conveyed, especially flat postal items. The inventive device comprises vertically pivotable conveying modules that are arranged one behind the other. The aim of the invention is to reduce the closing time required by the pivoted conveyor module component to go back to the level of the succeeding conveyor module component. The component of the conveyor modules is designed in such a way that said component can also be driven in the vertical direction, whereby said component is the front component when seen in the conveying direction. Immediately after a material to be conveyed (3) has been expelled and when the next material to be conveyed (3) is transported further, said front component of the conveyor module (1) that succeeds the expelling conveyor module (1) is pivoted against the component that is pivoted for expelling. Said front component is pivoted back upwards when the transport level of said component is situated underneath or at least at the same height in relation to the transport level of the previous, expelling conveyor module (1).

Description

description

Conveying device for the transport and discharge of conveyed goods

The invention relates to a conveyor device for transporting and discharging conveyed goods, in particular flat mail items, with vertically pivotable conveyor modules arranged one behind the other.

The goods to be conveyed can be sorted into further conveying devices or containers assigned to the conveying modules by targeted discharge at the respective conveying module (DE-OS 2 108 023). ■

In order to enable short gaps between the goods to be sorted and thus a high throughput, it is necessary to carry out the swiveling movements while the goods are still on the conveyor modules. For example, are already on a conveyor module that is pivoted downwards in the discharge position and is actually supposed to be transported horizontally. When this conveyor module is swung up and struck in the end position, the material to be conveyed loosely on the conveyor module can jump up and lose contact with the conveyor. This could result in undefined locations of the goods to be conveyed, including gaps. Furthermore, the sudden braking from the full swiveling speed is associated with increased wear and a high level of noise.

In order to avoid these disadvantages, to design the speed of the swivel movement so that the accelerations at the beginning and end of the swivel movements are as small as possible, DE 44 38 207 AI described the use of a crank mechanism with a sinusoidal movement for the drive of li P ⁾ P tr PJ ^• ö φ α <! ≤: Hl <! N σ? V vQ tQ σ 3 P iQ CΛ rΛ ^ _ ^ er P- σ <!

CD d P- P- c O 3 o P- Φ φ tu Φ Φ d: Φ J Φ P- P Φ Ω P- O: P- O: Φ 3 Φ P ⁾ Φ

P- CΛ 3 Ω ω P et 3 P 3 tr P P CΛ P- P P CΛ er P Ω tu ω tr 3 P Φ P P- ω P fl P o N Q tr er co rr ιQ 3 P 3? rt N rt Φ tr 3 Ω s: φ CΛ CL 3 er 3 rt tr P φ et a> Ω 3 Φ ^ Φ rt O p: z; • »M Φ P> P- et ω tr Φ Φ Φ Φ Φ ^ d P- D Cfl P Hi tr P- ιQ O: P α α P p- PPN 3 Ό P- 3 s: P ω P tc CO o O: Λ

3 Ω 3 φ P- <! Φ P Φ tu P- d N l P- Pi Φ rt d 3 o P "? V φ ^ Q iQ oo P_ P PJ tr -« «ω 3 φ Φ 3, α ω fl l-> φ φ 3 P- Φ LQ> O: P iQ P- dod Ω 3 φ CL P ¹

P SU to "Φ t-3 rt Φ 3 tu 3> 3 P 3 iQ rt Φ Φ rt rt φ rt tr α P Φ

DJ φ α Φ o Φ P Φ 3 "« «d s; er d CΛ Φ P Cfl Φ P- C0 Φ P Cfl

P d PJ r φ co 3 P- £ U: d Φ Φ d CΛ 3 Ό P- er rt Ω P ^ Q 3 Ω P> 3 Ω

Po ω EP P- _" 3 d Ω o P ¹ Ω 3 er P- P- P ¹ 3 rt P Ω φ Φ tr φ Φ Φ tu tr Φ P o tr

Φ Φ 3 tr P- 3 ^* α Φ 3 Φ Ω LQ (U: P ⁾ Φ d tr 3 3 ≤ iTj P s: o C s:

3 s: φ et -≤ d Cfl 3 α CΛ tr 3 E _^ Ω. φ P- M Φ tr Hi Φ P- CΛ d Φ er α PJ ^• P- 3 Φ Φ p- Φ rt fl Hl φ φ P ^< tr O 3 P 3 o 3 3 Ω H 3

CD Φ co er φ P 3 CΛ Cfl Φ O t 3 3 P P- Φ o α d Φ α tr P? tr? o tr; r Hl P ¹ tu φ tr Φ P ¹ 3 Hl P- O: P- PJ φ 3 er

O ^ 3 et Φ O:! D rt ex ^ O Ω α iQ N 3 3 PJ ιQ tr tu N CΛ 3 Φ φ d (U

PO: PJ SD: PPP ¹ Φ Φ O: P Cfl φ tr tu rt s: Φ α tr? d CΛ o P d EP P

P o ti α er s: 3 3 P rt P Hl ω P- CΛ P> α P Φ 3 3 M PJ CΛ Φ α tr CL 3 Φ H- P- O α CΛ W Ω P P- iQ 3 rt 3 do φ CL 3

P- Φ φ PJ P CL P N tu φ 3 3 P- tu tu Ω P tr ^ Q P α rt PJ tu Pi er 3 tu

CD P α Ω 3 Φ dd P tu 3 <£ td er tr tr P ¹ Φ Φ Ω Φ Φ er G: ιQ φ N 3 ^" O co P Cfl LQ Ω <Φ CΛ Φ ω O: P- α ω P- Φ tr Φ P φ Φ er

CΛ P 3 ≤ CL d Cfl d tr Φ> 1 3 ιQ P- 3 tr φ φ tu O co Pi Φ Φ P- P- Φ o et P- oc ι-3 3> Ω rt PO: d φ d cP iQ 3 et o M Φ 3 3 3 P tr ω er P- ¹ PP tr et P Φ ω α. 3 rt P- er σ P ^J 3 ω φ 3 m α d Ω Φ O 0 ⁾ ω P ^J SS Φ P- α 3 Ω Φ Φ LQ o Φ rt tr ≤ d Ώ α t? A PJ PJ

P- SD co tr 3 3 -c CΛ Φ φ 3? Φ P 3 P 3 Φ Φ P Φ ^ φ 3 LQ Ω er D CΛ c O CΛ Ω d P- DJ P »^ s iQ <J er Ω 3 JO: ^■ L φ tr Φ IV)

EP Ω 3 iQ α ^• ö 3 tr Cfl rt! PO: Φ Q ^ tu W Φ Φ Φ tr ^ QP Φ = ε <j er m tr Φ Φ o 3 Φ Φ d Φ P- P 3 Φ O: P 3 PP 3 3 CO Φ Φ P- J P- CL O

CD 3 Cfl PP Φ 3 P ω POQ? R P tQ Hi er co PJ Φ ¹ IQ co φ P

^• s φ φ Ω rt Φ dd N o tr Φ rt tu α CΛ P- d rt ^ Φ P P- Φ o 3 P

CD Φ P 3 tr 3 3 P fl Φ d Ω ta et P Φ 3 Φ Ω 3 3 3 Φ NO: P 3 tQ * _* φ P- i ω s: P- P- P 3 rt tr P- P 3 r P tr J α Φ P Φ PPO Φ oo

C Φ Tl Φ 3 <! co 3 P ^< Ω 3 O • n Φ ιQ £ Ω d Φ P CΛ Φ 3 Cfl is Ω 3 "

3 P- O: 3 Φ P- ιQ * 1 tu Φ tr ιQ O: P- Φ tr 3 3 α Φ P- d rt φ tr rt

LQ Φ o P »? Φ tu Ω O: 3 d et d P N et 3 ιQ φ Tl J CL P Ω ^ P> P- s: d

CΛ P α rr co d tr 0 ⁾ P fl fl P <P "d Φ - 3 O: 3 d 3 tr co O: er rt Φ 3

P ⁾ φ iQ Φ et CΛ d α • Ö Φ 3 O rt Φ iQ P ^ Q Φ ¹ P P- P o et P P- 3 iQ er CΛ 0 ⁾ P ≤ Φ 3 CΛ φ O 3 ^ QP Φ PP 3 Φ 3 P- t- <C rt Ω α Φ P- t Φ ια 3 ιQ P- 3 p- iQ PP α P- 3 d CΛ φ d: φ tr d tr P Φ 3 er 3

Φ • n ιQ P- P Cfl Φ rt Φ 3 rt φ Φ P ¹ o 3 N Ω> iQ Ω P <i P ¹ PJ CΛ P Φ ω O: et ω ω o P- P- Φ P CΛ α d tr P rt? iQ Φ H rt rt 3 Φ s; <n li 3 Φ. SU ω Ω Φ 3 P Φ d Φ ¹ s: CΛ Φ d: PP CΛ o P φ Φ O tr P): PP <! Φ tr d P Φ Pi φ _^ (U: P- Cfl α 3 rt er tr rt Φ CL er 3 iQ P

P ¹ Φ Ω 3 σ H, o P- s: Φ Cfl tl P rt ω 3 Ω tu .. <Φ d O: OPPP ¹ d ιT) o P tr P- P 3 Φ 3 tr Φ P Φ Cfl tr tr Φ P 3 tr EJPP ¹ Φ M 3 Φ ω 3 ω to Φ iQ iQ Φ 3 3 tl li P- Φ P- P- P- P- φ PP Φ φ P- 3 iQ Cfl co o rt o ω P "Φ 3? J P- O: er p- Φ iQ ιT! Φ P co <Φ 3 • 3 ω P- er er CL Φ o φ φ Φ P ¹ rt Ω cn P tu Ω? D Ω O 3 iQ o Ω Φ Φ P ¹ 3 dr

3 d N Φ P- DJ P3 Φ 3 ^J rt P α tr s: CΛ CΛ Φ CΛ α 3 ^" 3 Φ C 3 tr Pi 3 PJ P ¹ t! PP Ω ^ QP 3 Pi Φ Φ • et P- Ω P - P- φ P- P- 3 P: CΛ Φ P- • iQ N PJ

P- ω P- 3 tr Φ 0 ⁾ OP tu P • φ tr 3 rt 3 φ Φ Q. * _* Φ P rt 3 3 Φ d iQ ω Ω <O: φ P 3 HP ¹ L ^ Q d - Φ er Φ P α α α 3 3 φ et φ tr Φ ^ QP rt ω Φ ιQ P- d Λ ^ N Φ P- • 3 co d P CΛ φ ¹ ^" : ri-.

• 3 p et P 1 Φ 1 P- Φ Φ rt ιQ O: d P φ o d 3 Ω <PJ s: P- Φ- ^

1 1 tc 3 3 Cfl Φ φ H E Hi iQ tr CΛ Φ Ω fl ^ O:

O: "1 Φ 1 1 1 N 1 Φ o 3 tr P

1 P d 3 3 3 φ 1

Advantageous embodiments of the invention are specified in the subclaims.

To achieve the shortest possible distances between the conveyed goods, it is favorable that the front part of the conveying module following the discharging conveying module is only pivoted downwards during the closing movement of the conveying module to be discharged until both conveying modules with the conveying level of their adjoining parts are at approximately the same height are located and then immediately swung up again.

To reduce the effort, it is advantageous to guide the front part of the conveyor module vertically in a straight line and to guide the rear part in such a way that the necessary horizontal movement components can be carried out. In an advantageous drive variant, the front part of the conveyor module is connected to a controllable lifting element. For example, a lifting magnet or a pneumatic lifting cylinder can be used as the lifting element.

A spring element can also act as an energy store on the front part of the conveyor module in the conveying direction.

It is also advantageous to connect the rear part of the conveyor module in the conveying direction to the push rod of a crank mechanism in order to achieve a sinusoidal vertical movement.

The invention is then explained in more detail in an exemplary embodiment with reference to the drawing. It shows

1 shows a schematic side view of a conveyor module with an endless conveyor belt in the horizontal transport position 2 shows a schematic side view of a conveyor module in the discharge position

3a-c show schematic side views of three conveyor modules with two flat conveyed goods in different transport phases

As can be seen in FIG. 1, a conveyor module 1 has a driven rotating conveyor belt 2, which is guided over two rollers. The extended axis of the roller on the incoming side is also the swivel axis of the module for swiveling from the conveying position to the discharge position and back. On the other hand, the extended axis of the roller on the outgoing side is also the swivel axis of the module for swiveling the front one in the conveying direction

Part of the conveyor module during the closing movement of the upstream conveyor module after being discharged, in order to ensure that the goods to be conveyed from the upstream conveyor module are taken over without any problems even before its horizontal end position.

The front part of the conveyor module 1 in the conveying direction is, like the rear part, in the upper end position, which is occupied in the largest time span for a conveyed item on the conveyor module 1 during a transport cycle. In order that this pivoting movement is carried out as energy-saving as possible, this upper end position is held by means of an energy store in the form of a compression spring 13. If the module part is to be pivoted downwards on the inlet side, a lifting element 12 (in this case a lifting magnet) is activated, which acts on the elongated axis of the deflection roller 'on the front conveyor module part in the conveying direction. After deactivating the lifting element 12, this conveyor module part is returned to its upper end position by the compression spring 13. suppressed. On the conveyor belt 2 there is currently a conveyed item 3. In order to carry out the swiveling movement for discharging, the roller is mounted on a push rod 7 of a crank mechanism on the outgoing side. A crank mechanism was selected so that the movement is sinusoidal and thus there are no impermissibly high accelerations that would cause the goods to jump on the conveyor belt 2. The conveyor belt 2 is in accordance with FIG 1 in the horizontal 'conveying position from module to module, the crank mechanism is also just at top dead center. The arrow indicates the half turn of the crank to be carried out to the bottom dead center for the discharge position in FIG. 2, ie the crank diameter corresponds to the discharge stroke of the conveyor module. The arrow in FIG. 2 indicates that the crank 6 makes a half turn upwards in the opposite direction of rotation for pivoting up.

Since this drive should also consume as little energy as possible, but movement times should be as short as possible, an energy store in the form of a tension spring 4 is used, which is connected to the crank 6 at the connection point to the push rod 7. When a material to be conveyed 3 located on the conveying module 1 is discharged downwards as a result of half a turn of the crank 6 downward, the tension spring 4 is tensioned by the drive and the mass of the conveying module 1 and the conveyed goods 3. If the conveyed goods 3 have been discharged, the conveying module 1 must then swivel upwards as quickly as possible in order to avoid that the following conveyed goods 3 are pinched if there are short gaps between the conveyed goods 3. The tensioned spring enables this process to be carried out quickly with relatively little energy. To limit the crank movement, an upper stop 9 and a lower stop 10 are provided, the upper stop 9 being just behind top dead center and the lower stop 10 at bottom dead center or just before it. The drive can be implemented, for example, by a stepper motor or by a direct current gear motor. The counter bearing of the tension spring 4 is fastened to a spring suspension 5 and is located above the upper stop 9. As a result, the crank 6 is pulled by the tension spring 4 against the upper stop 9 into a slight kink position and also against the lower stop 10 when it is over the imaginary jump line 11, which runs straight through the counter bearing and the crank axis of rotation 8, is moved out. A defined stay of the crank β in the end positions is thus ensured without the need for special locking means or drives with energy-consuming holding functions.

Due to the high dynamics of the rotary motion at a rotational speed of V ax = 3 revolutions / second, stopping which ends quickly (<50 ms) and exactly at the stops 9, 10 is not possible without angle detection and control, since the stop point influences, for example is through

• Load on the conveyor module due to the material being conveyed (weight variance) • Motor winding temperature

• bearing friction

• All kinds of manufacturing tolerances (feed module weight, motor tolerances)

• Operating voltage of the DC motor

These factors also influence the pivoting times of the conveyor module 1. In order to guarantee the same swiveling times and defined stop points, a DC motor is operated with a • slightly higher voltage than the nominal voltage

(approx. 10-20% more), which would lead to a fast turnaround time if the conveyor module was only slightly loaded.

A motor control system gains from the movement of the motor, recorded via two devices for angle detection, implemented as Hall sensors, a device for current detection and a thickness, height and length sensor possibly located in front of a sorting section, in order to use a pulse width modulation to measure the motor to influence that the movement does not fall below a predetermined minimum time even with a lightly loaded conveyor module and that the dynamics also approximate a set curve. The device for current detection enables a reliable determination of the load torque, since I = f (M) for the DC motor.

The thickness, height and length sensor and its measurement information replace an elaborate weighing assuming proportionality between volume and weight.

In order to detect the direction / speed of rotation of the motor, two Hall sensors were staggered on the motor shaft.

The power reserves not used in the case of very light consignment goods are then available to compensate for the load factors and disturbance variables listed above, as a result of which a constant turnover time is achieved. The starting point of the braking and its duration is also derived from the sensor information by the motor control. to enable the stops 9, 10 to be approached exactly.

This eliminates elastic stops, unnecessary wear,

Noises, etc. avoided. The starting point of the braking and its duration is determined dynamically depending on the load torque and the angular velocity / angular position of the crank mechanism. The motor control can control the motor so that the crank no longer has any kinetic energy at the stops.

For a particularly smooth and jerk-free pivoting of the conveyor module 1, the angular velocity of the drive motor has a sinusoidal course, so that the pivoting process of the conveyor module 1 has an adjustable course.

In the case of a further simple drive design without angular position sensors and motor control, which can be used if, for example, the maintenance of certain swiveling times of the conveyor modules 1 is not particularly demanding or the influences of the disturbance variables are small (e.g. lower weight variance), the time-controlled one is Drive designed in such a way that the elastic stops take up part of the kinetic energy of the crank mechanism even under different operating conditions (high operating voltage, low bearing friction, minimally loaded conveyor module).

Since the front part of the conveying module 1 in the conveying direction is only pivoted down when unloaded and is only pivoted upwards with the front part of a piece good, this drive is not subject to such high requirements that a correspondingly dimensioned lifting element 12 with a spring element 13 is sufficient here is. The sequence of the pivoting movements of the front part of the conveyor modules 1 with the revolving conveyor belts 2 is shown in FIG. 3a-c, for the sake of clarity only the drive of the front part of the conveyor module 1 performing the oncoming pivoting movement is shown. Flat consignments are transported as goods 3. According to FIG. 3a, the conveyed goods 1 are just leaving the downwardly pivoted conveyor module 1. The following conveyed goods 3 are already partially on the downwardly pivoted conveyor module 1, but are to be transported further. Immediately after the conveyed material 3 to be discharged has left the conveying module 1, it is swung up again. At the same time, the front part of the subsequent conveyor module 1 in the conveying direction is pivoted downwards by means of the lifting element 12 and the compression spring 13 at least until its conveying level has reached the conveying level of the upwardly pivoting conveying module 1, which the previous conveyed item 3 has just discharged (FIG 3b). Then this front part of the subsequent conveyor module 1 is pivoted upwards again in the conveying direction, so that at the end of this movement cycle both conveyor modules 1 are in the horizontal end position (FIG. 3c). Because of this counter-pivoting, the distance between the goods to be conveyed can be shortened so that a transfer to the subsequent conveyor module 1 can already take place when both conveyor modules 1 are at the same level at the transfer point and not only when the horizontal end positions have been reached.

Claims

claims

1. Conveying device for transporting and discharging conveyed goods, in particular flat consignments, with vertically pivotable conveying modules (1) arranged one behind the other, whose rear parts in the conveying device, on which the conveyed goods (3) leave the conveying modules (1), are vertically displaceably mounted are and which can be swiveled into a horizontal transport position or into a discharge position by means of drive elements, depending on the control, characterized in that the front part of the conveying modules (1) in the conveying direction can also be vertically displaced by drive elements for executing a swiveling movement and the displacing movement can thus be carried out that immediately after the discharge of a conveyed material (3) simultaneously with the closing movement of the rear part of the respective discharge module (1) in the conveying direction, the front part of the following conveying module (1) in the conveying direction so down and again is pivoted upwards into the horizontal position so that its transport level is always below or at most at the same height as the transport level of the swiveling part of the upstream, diverting conveyor module (1) and that the distance between the conveyed goods (3) and the conveyor speed can be selected so are that the conveyed goods (3) following the conveyed goods (3) that have just been discharged and cannot be discharged by the upstream conveying module (1) concerned reach the exit of this conveying module (1) as soon as their transport level reaches the transport level of the subsequent conveying module (1) has reached.

2. Conveying device according to claim 1, characterized in that the forward part in the conveying direction of the conveying module (1) discharging conveying module (1) during the closing movement of the discharge conveyor module (1) is only pivoted down until both conveyor modules (1) are at approximately the same level with the conveyor level of their adjoining parts and are then immediately pivoted up again.

3. Conveying device according to claim 1, d a d u r c h i g e k e n n z e i c h n t that the front part of the conveyor modules (1) in the conveying direction is guided vertically straight and the rear part is guided in the conveying direction so that horizontal movement components necessary for pivoting can be carried out.

4. Conveying device according to claim 3, d a d u r c h g e k e n n z e i c h n e t that the front part of the conveyor module (1) is connected to a controllable lifting element (12).

5. Conveying device according to claim 4, d a d u r c h g e k e n n z e i c h n e t that a spring element (13) engages on the front part of the conveyor modules in the conveying direction.

6. Conveying device according to claim 1 or 3, d a d u r c h 'g e k e n n z e i c h n e t that the rear part of the conveyor module (1) in the conveying direction is connected to the push rod (7) of a crank mechanism.