Electro-pneumatics Seminar

Contents

Part A – Exercises

Exercise 1: Realising a sorting device ____________________________________A-3 Exercise 2: Realising a shut-off device___________________________________A-15 Exercise 3: Realising a lid press ________________________________________A-25 Exercise 4: Realising the operation of a hinged lid _________________________A-35 Exercise 5: Realising a diverting device __________________________________A-43 Exercise 6: Actuation of a stacking magazine _____________________________A-53 Exercise 7: Sorting of packages ________________________________________A-65 Exercise 8: Actuation of a sliding platform _______________________________A-73 Exercise 9: Expanding a diverting device _________________________________A-81 Exercise 10: Designing a stamping device________________________________A-91 Exercise 11: Realising a pallet loading station __________________________ A-101 Exercise 12: Eliminating a fault on the pallet loading station_______________ A-107

© Festo Didactic GmbH & Co. KG • 541090

A-1

Contents

A-2


Exercise 1: Realising a sorting device

Training aims

• To familiarise yourself with the design and mode of operation of a single-acting cylinder. • To familiarise yourself with the design and mode of operation of a 3/2-way solenoid valve. • To be able to identify and draw various types of actuation of directional control valves. • To be able to explain and design an example of direct actuation.

Problem definition

A sorting device is to be used to sort water samples according to the size of the sample bottle. Design a control system whereby this process can be carried out.

Parameters

• A single-acting cylinder is to be used. • The control of the cylinder is to be effected by means of a pushbutton. • In the event of a power failure the cylinder piston rod is to return into the retracted end position.

Project task

1. Answer the questions or carry out the exercises regarding the fundamentals of the training contents listed. 2. Draw the pneumatic and electrical circuit diagram. 3. Simulate the electropneumatic circuit diagram and check its correct functioning. 4. Compile an equipment list. 5. Carry out the pneumatic and electrical circuit assembly. 6. Check the circuit operation.


A-3


Positional sketch

Sorting device

1. Pressing of a pushbutton causes the piston rod of a single-acting cylinder to push the sample bottle off the conveyor. 2. When the pushbutton is released, the piston rod is to return into the retracted end position.

A-4



Exercise 1: Realising the operation of a sorting device Name:

Date:

Fundamentals: Function of pneumatic working components

Sheet 1 of 7

Pneumatic working components can be divided into two groups: • Working components using linear movement • Working components using rotary movement – Describe the function of the working components shown. Symbol 1

Symbol 2

Symbol 3

Description of function Symbol 1:

Symbol 2:

Symbol 3:


A-5



Date:

Fundamentals: Completing solenoid valve symbols

Sheet 2 of 7

– Complete the individual symbols with the help of the corresponding component descriptions. Description

Symbol

Directly actuated 3/2-way

2

solenoid valve, normally open, with manual override, with spring return

1

3

Pilot actuated 3/2-way solenoid

2

valve, normally closed, with manual override, with spring return

A-6

1

3




Date:

Fundamentals: Normal positions of directional control valves

Sheet 3 of 7

An electrically actuated 3/2-way solenoid valve has two switching positions. It can be in the normal position (unactuated) or in the switching position (actuated). In the normal position the valve can be open or closed. – Describe the effects on the motion sequence of the following application arising as a result of the different normal positions. The single-acting cylinder shown is controlled by an electrically actuated 3/2-way solenoid valve. 2 1M1

Description: Normal position closed


1

2

3

1M1

1

3

Description: Normal position open

A-7



Date:

Fundamentals: Direct and indirect actuation

Sheet 4 of 7

An electrically actuated solenoid valve can be actuated either directly or indirectly. – Describe the difference with the help of the following application: Electrical actuation of a spring-returned 3/2-way solenoid valve using a pushbutton. Description: Direct actuation

A-8

Description: Indirect actuation




Date:

Design and function of an electrical switch

Sheet 5 of 7

Switches are basically divided into pushbutton and control switch designs and perform the function of a normally open or normally closed contact or changeover switch. – Describe the design and function of the switches shown. Symbol 1

Symbol 2

3 4

Symbol 3

1

2 2

4 1

Description: Design/Function


A-9



Date:

Fundamentals: Mode of operation of different valve types

Sheet 6 of 7

Electrically actuated directional control valves are switches with the help of solenoids. Basically, these can be divided into two groups: • Spring-return solenoid valves • Double solenoid valves – Describe the differences between the two groups with regard to function and behaviour in the event of power failure. Valve type

Mode of operation

Spring-return valve

Double solenoid valve

A-10




Date:

Fundamentals: Port designations of valves

Sheet 7 of 7

In order to prevent incorrect tubing up of directional control valves, the valve ports (working and pilot lines) are identified in accordance with ISO 5599, both on the valve itself and in the circuit diagram. – Describe the meaning and function of the designations below. Designation

Meaning, function

3

12

10


A-11



Date:

Completing the pneumatic and electrical circuit diagram

Sheet 1 of 1

– Complete the pneumatic and electrical circuit diagram for the sorting device.

2

1

3

Pneumatic circuit diagram +24 V

1

0V

Electrical circuit diagram

A-12




Date:

Compiling the equipment list

Sheet 1 of 1

Apart from the circuit diagram, comprehensive project documentation also requires an equipment list. – Compile the equipment list by entering the required equipment in the table below. Quantity

Description

Equipment list


A-13


A-14


Exercise 2: Realising a shut-off device

Training aims

• To familiarise yourself with the design and mode of operation of a double-acting cylinder. • To be able to explain and design an example of direct actuation.

Problem definition

In a water treatment system numerous pipes need to be opened or and closed by means of shut-off devices. A test setup is to be used to find a possible means of actuating the shut-off valve.

Parameters

• A double-acting cylinder is to be used. • The cylinder control is to be effected by means of a pushbutton. • In the event of power failure the cylinder piston rod is to return into the retracted end position.

Project task

1. Answer the questions or carry out the exercises regarding the fundamentals of the training contents listed. 2. Design the pneumatic and electrical circuit diagrams. 3. Simulate the electropneumatic circuit diagram and check its correct functioning. 4. Compile an equipment list. 5. Carry out the pneumatic and electrical circuit assembly. 6. Check the circuit operation.


A-15


Positional sketch

Shut-off device

1. Pressing of a pushbutton is to cause the valve to open the slide 2. Releasing of the pushbutton is to cause the slide to close.

A-16



Exercise 2: Realising a shut-off device Name:

Date:

Fundamentals: Comparison of directly actuated and pilot actuated valves

Sheet 1 of 5

Differentiation is made between directly actuated and pilot actuated solenoid valves with regard to the type of actuation of the valve piston. – Compare these two valve types and describe the respective advantages and disadvantages. Directly actuated valve


Pilot actuated valve

A-17



Date:

Port designations of valves

Sheet 2 of 5

In order to prevent incorrect tubing up of directional control valves, valve ports (working and pilot lines) are identified in accordance with ISO 5599-3, both on the valve itself and in the circuit diagram. – Describe the meaning and function of the designations below. Designation

Meaning, function

4

14

82/84

A-18




Date:

Fundamentals: Mode of operation of a solenoid valve

Sheet 3 of 5

A valve symbol provides information regarding the function of the valve, i.e. the number of ports, switching positions and type of actuation, but not about the constructional design. – Describe the mode of operation of the directional control valve shown. 4

2

1M1 5

1

3

Description: Mode of operation of a directional control valve


A-19



Date:

Fundamentals: IP classification

Sheet 4 of 5

Depending on the installation and ambient conditions, electrical equipment is protected by means of a housing or cover. The required protection class against dust, humidity and foreign objects is to be identified. The classification IP 65 is shown on a valve – Describe the meaning of this classification. Description of IP 65 classification

A-20




Date:

Fundamentals: Symbols of pneumatic cylinders

Sheet 5 of 5

Piston rod cylinders with linear action can be divided into two groups: • Single-acting cylinders • Double-acting cylinders – Describe the meaning of the cylinder symbol shown. Symbol 1

Symbol 2

Description of symbolic representation


A-21



Date:

Completing the pneumatic and electrical circuit diagrams

Sheet 1 of 1

– Complete the pneumatic and electrical circuit diagrams for the sorting device.

4

5

2

1

3

Pneumatic circuit diagram +24 V

1

0V


A-22




Date:


Sheet 1 of 1


Description

Equipment list


A-23


A-24


Exercise 3: Realising a lid press

Training aims

• To familiarise yourself with the design and mode of operation of a double-acting cylinder. • To be able to explain and design an example of indirect actuation.

Problem definition

In a filling plant, wall or ceiling paints are filled into plastic pots. Once filled, slip-lids are to be pressed onto the plastic pots.

Parameters

• A double-acting cylinder is to be used. • The cylinder control is to be effected indirectly and by means of a pushbutton. In the event of power failure the cylinder piston rod is to return into the retracted end position.

Project task



A-25


Positional sketch

Filling of pots of paint

1. Pressing of a pushbutton is to cause the pressing ram to advance and the slip-lid to be pressed on. 2. Once the pushbutton is released, the pressing ram is to be returned into the initial position.

A-26



Exercise 3: Realising of a lid press Name:

Date:

Fundamentals: Mode of operation of relays

Sheet 1 of 4

A relay is a remotely controlled electromagnetically actuated switch with several contacts. The main components are: • Coil with core • Winding of coil • Contact set • Return spring • Armature • Terminal lugs

The following illustration shows a sectional representation of a relay. – Allocate the component designations. 2

3

1 4 5

A1 A2

7


4 2

1

6

A-27


Exercise 3: Realising a lid press Name:

Date:

Fundamentals: Design and mode of operation of relays

Sheet 2 of 4

– Describe the mode of operation of a relay. Description of mode of operation of a relay

A-28




Date:


Sheet 3 of 4

One or several contacts can be switched by a relay coil. Relays with normally closed, normally open or changeover contact(s) are used depending on the function required. Additional designs of electromagnetically actuated switches are for instance a remanence relay, the time relay with switch-on delay, the time relay with switch-off delay and the contactor. – Describe the design and contact alignment of the relays shown. Description of design/contact alignment

Symbol

A1

A2 A1

A2


13

14

23

24

31

41

32

42

12 14

22 24

32 34

42 44

11

21

31

41

A-29



Date:


Sheet 4 of 4

– List the possible applications of relays in electrical or electropneumatic control systems. Description: Possible applications

A-30




Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the lid press.

Pneumatic circuit diagram


A-31



Date:


Sheet 2 of 2

+24 V

1

0V

2

11

12 14

21

22 24

31

32 34

41

42 44


A-32




Date:


Sheet 1 of 1


Description

Equipment list


A-33


A-34


Exercise 4: Realising the operation of a hinged lid

Training aims

• To be able to design an example of indirect actuation • To familiarise yourself with logic operations • To be able to select solenoid valve according to requirements

Problem definition

Plastic granulate is to be filled from a storage silo. The silo is to be opened or closed using a hinged lid. The process is to be effected from two points.

Parameters

• A single-acting cylinder is to be used. • The cylinder control is to be indirect and via hand levers. In the event of power failure, the cylinder piston rod is to advance into the forward end position.

Project task



A-35


Positional sketch

Filling of plastic granulate

1. Pressing of either one of the pushbuttons is to cause the hinged lid to open and to empty the bulk material from the container. 2. Once the pusbutton is released, the hinged lid closes.

A-36



Exercise 4: Realising the operation of a hinged lid Name:

Date:

Fundamentals: Converting solenoid valves

Sheet 1 of 3

In industrial practice, there are numerous different requirements with regard to a valve. If a valve with all the required features is not available, it is often possible to use a valve with a different number of ports. The table below lists a selection of directional control valves frequently in use in industrial applications. – Describe the valve types shown. – Identify all solenoid valves that can be replaced by a 5/2-way solenoid valve of the type shown.. – If measures are required to convert the valve, describe these. Note By „conversion measures“ we understand the simplest of conversions such as the sealing of working ports 2 or 4 using a blanking plug. 4

2

14 1M1 5

1

Symbol

3

Description of valve type

Replacement possible

Description of necessary conversions

2 12 1M1

1 2

12 1M1

1

3 2

10 1M1

1 4

14 1M1

1

3 2

3


A-37



Date:

Fundamentals: Selecting solenoid valves

Sheet 2 of 3

Valves are selected according to the following criteria: • Exercise definition, • Required behaviour in the event of power failure, • Minimum possible overall costs The following valves are available for selection for the actuation of a single-acting cylinder: • A pilot actuated, spring return 3/2way solenoid valve with manual override, • A pilot actuated, spring-return 5/2-way solenoid valve with manual override – Select a valve and explain the reasons for your decision. Note Apart from the cost of the valve, the above overall costs also include the cost of installation, maintenance and storage for replacement parts. Valve type

A-38

Reason




Date:

Fundamentals: Logic operations: The OR function

Sheet 3 of 3

Triggering the advancing of a cylinder piston rod is to be possible using two pushbuttons S1 and S2. If at least one of the two pushbuttons is actuated, the valve coil 1M1 is energised, the solenoid valve 1V1 switches into the actuated position and the piston rod advances. If both pushbuttons are released, the valve switches into the initial position and the piston rod retracts. – Create the appropriate function table and the logic symbol. Note 0 means: Pushbutton not actuated, i.e. piston rod does not advance 1 means: Pushbutton actuated, i.e. piston rod advances S1

S2

1M1

1V1

Function table

Logic symbol


A-39



Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the operation of the hinged lid.


A-40




Date:


Sheet 2 of 2

+24 V

2

1

3

12

14

K1 11

A1 K1

1M1 A2

0V 11

12 14

21

22 24

31

32 34

41

42 44



A-41



Date:


Sheet 1 of 1


Description

Equipment list

A-42


Exercise 5: Realising a diverting device

Training aims

• To familiarise yourself with the design and mode of operation of a double-acting cylinder. • To familiarise yourself with the design and mode of operation of a double solenoid valve.

Problem definition

Packages are to be pushed from one conveyor to another via a diverting device.

Parameters

• A double-acting cylinder is to be used. • The cylinder control is to be effected indirectly and via a pushbutton. In the event of power failure the cylinder piston rod is to remain in the current position.

Project task

1. Answer the questions and carry out the exercises regarding the training contents listed. 2. Design the pneumatic and electrical circuit diagrams. 3. Simulate the electropneumatic circuit diagram and check its correct functioning. 4. Compile an equipment list. 5. Carry out the pneumatic and electrical circuit assembly. 6. Check the circuit operation.


A-43


Positional sketch

Diverting device

1. Pressing of a pushbutton is to cause the frame of the diverting device to be advanced. The package is transferred and transported away. 2. Pressing of another pushbutton causes the frame to be moved into the initial position.

A-44



Exercise 5: Realising a diverting device Name:

Date:

Fundamentals: Use of solenoid valves

Sheet 1 of 4

Two factors are to be considered regarding the question as to which valve type is to be used for a particular application: • Duration, i.e. time frame, • Quantity or frequency of required switching operations. In order to utilise a directional control valve as efficiently as possible, you will need to decide in each case whether the use • of a double solenoid valve or • a spring-return directional control valve is more cost effective for the required application. – Decide whether a double solenoid or a spring-return solenoid valve seems more cost effective for the applications listed and explain the reasons for your choice. Application 1 The clamping cylinder of a milling device is to firmly hold in position a workpiece for the duration of a milling operation (duration of approx. 10 min, 60 clamping operations per day). Valve type

Reason

Application 2 The ejecting cylinder of a sorting device is to push defective workpieces from a conveyor (duration of approx.1s, 600 ejecting operations per day). Valve type


Reason

A-45



Date:

Fundamentals: Mode of operation of a solenoid valve

Sheet 2 of 4

– Describe the mode of operation of the directional control valve shown.

4

2

5

3

1M1

1M2 1

Description of mode of operation of a directional control valve

A-46




Date:

Fundamentals: Calculating the current consumption of a valve coil

Sheet 3 of 4

A spring-return solenoid valve is to be switched via pushbutton S1. – Calculate the current consumption of the valve coil 1M1 at a voltage supply of 24 V DC and a coil resistance of 48 Ω (Ohm). +24 V

1

13 S1 14

1M1

0V Current consumption in 1M1


Power rating of 1M1

A-47



Date:

Fundamentals: Calculate the current consumption of a valve coil

Sheet 4 of 4

– Would the current consumption in 1M1 be the same, higher or lower if the above valve coil is connected to a 24V AC voltage? Explain the reasons for your answer. Identical

A-48

Higher

Lower

Reason




Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the diverting device.

1



A-49



Date:


Sheet 2 of 2

+24 V

1

0V

2

3

11

12 14

11

12 14

21

22 24

21

22 24

31

32 34

31

32 34

41

42 44

41

42 44

4


A-50




Date:


Sheet 1 of 1


Description

Equipment list


A-51


A-52


Exercise 6: Actuation of a stacking magazine

Training aims

• To be able to use a double-acting cylinder. • To familiarise yourself with the design and mode of operation of a double solenoid valve. • To familiarise yourself with the option of sensing the end positions of cylinders.

Problem definition

Wooden boards are to be pushed from a stacking magazine into an assembly device.

Parameters

• The forward end position of the cylinder is to be sensed.

Project task



A-53


Positional sketch

Stacking magazine

1. Pressing of a pushbutton causes a wooden board to be pushed out of the stacking magazine. 2. Once the forward end position is reached, the slide is moved into the initial position.

A-54



Exercise 6: Actuation of a stacking magazine Name:

Date:

Fundamentals: Components of an electropneumatic system

Sheet 1 of 6

The components of an electropneumatic system are represented in a pneumatic circuit diagram and/or in an electrical circuit diagram. – Determine where the components below are to be represented. Component



Manually operated pushbutton Cylinder Valves Valve coils Relay Electromechanical limit switch Electronic proximity sensor Indicating devices


A-55



Date:

Fundamentals: Components of an electropneumatic system

Sheet 2 of 6

The function of sensors in electropneumatic control systems is to acquire information and to transmit this for signal processing. – What function(s) can an electromechanical limit switch fulfill in an electropneumatic control system? Description: Function(s) of electromechanical limit switches

A-56




Date:

Fundamentals: Representation of limit switches

Sheet 3 of 6

Limit switches can be actuated in different ways, via the function of a normally closed or normally open contact or changeover switch and, in the normal position of the system, can be either actuated or unactuated. – Describe the appropriate design or function of the symbols shown. Description: Design/function

Symbol 2 1 4 1


A-57



Date:

Fundamentals: Creating a logic element table

Sheet 4 of 6

One possibility of recording the allocated contacts of a relay is by means of listing these in a logic element table. – Create the logic element tables for relays K6 and K9. +24 V

10

11

12

13

14

15

16

17

18

19

... 14

12

12

K5

14

K6 11

12

14

K2 11

12

14

K7 11

12

14

K4 11

12

14

K8 11

14

12 K3

11

12

14

K9 11

34

32

34

32

K6

K7

11

31

31

14

12 K1

11

22

24

K9

22

24

K6 21

K8

34

K9

32

34

K8 31

31

A1 K9

A2

32

21

A1 K8

A2

24

22

21

A1 K7

A2

24

K7 21

A1 K6

22

1M1

2M1

A2

0V

...


Logic element table

Description: Logic element table

K6

K9

A-58




Date:


Sheet 5 of 6

Another method of recording the allocated contact sets of a relay can be seen in the electrical circuit diagram below. +24 V

1

2

4

3

5

6

8

7

11

10

9

21

12

25

14

K11

NA EMERGENCY 22 STOP

2B1

13

2B2 S1 Start

13

14 12

12 K5

14 12

14 12

K6 11

14

16 14 12

K7 11

11

17

14 12

K4 11

14 12

K8 11

18 14 12

K3 11

20

19 14 22

K9 11

24 12

K1 11

22

21 14 32

K10 21

34

23 34

32

K6 11

26

34

32

34 22

32

K8

31

31

24

K7

K9

31

34

K11 21

12

1B2

32

K11 11

1B1

27 24

22

24

K3

31

31

21

14

12 K1

11

24

22 K10

A1 K11

A1 K1

K2

A2 0V

A1

A1 K3

A2

A1 K4

A2

A1 K5

A2

K6

K7

24

22 K8

24

22

21

21

A1

A1

A1

A1

A1

K8

A2

K9

A2

44

42 K7

K9

21

K7

A2

24

22

21

K6

A2

24

22

21

44

42 K8

1M1

44

42 K9

41 2M1

34

32 K10

41

41 2M2

31 1M2

K10

A2

A2

A2

11

12 14 .11

11

12 14 .12

11

12 14 .14

11

12 14 .18

11

12 14 .16 11

12 14 .12

11

12 14 .13

11

12 14 .15

11

12 14 .17

11

12 14 .19

11

12 14 .21

21

22 24 .25

21

22 24 .20

21

22 24

21

22 24 .27

21

22 24

21

22 24

21

22 24 .14

21

22 24 .16

21

22 24 .18

21

22 24 .20

21

22 24 .12

31

32 34 .27

31

32 34

31

32 34

31

32 34

31

32 34

31

32 34

31

32 34 .22

31

32 34 .23

31

32 34 .24

31

32 34 .26

31

32 34 .26

41

42 44

41

42 44

41

42 44

41

42 44

41

42 44

41

42 44

41

42 44

41

42 44 .22

41

42 44 .23

41

42 44 .24

41

42 44

1A1+

2A1+

2A1-

1A1-



A-59



Date:


Sheet 6 of 6

– Complete the information regarding the relays shown by: Indicating the current path in which the respective contact is used and specifying the function fulfilled by the contact set (normally open or normally closed contact). Relay

Current path

Function:

Function:

Normally open contact

Normally closed contact

Relay K9

Relay K10

A-60




Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the stacking magazine. 1A1

1V2

1V1

1

1

2

2

4

5

1V3

2

1

3



A-61



Date:


Sheet 2 of 2

+24 V

1

3

2

12

4

14

K1

A1

14

K2 11

K1

12

11

A1 K2

A2 0V

A2

11

12 14

11

12 14

21

22 24

21

22 24

31

32 34

31

32 34

41

42 44

41

42 44


A-62




Date:


Sheet 1 of 1


Description

Equipment list


A-63


A-64


Exercise 7: Sorting of packages

Training aims

• • • •

Problem definition

Packages are to be transported on a conveyor past workstations. The packages can be diverted by means of deflectors.

Parameters

• A double-acting cylinder is to be used. • The cylinder control is to be effected indirectly via pushbuttons and electromechanical limit switches. • Triggering of the advancing movement is to be possible only if the piston rod is in the retracted end position.

Project task


To be able to calculate piston forces according to specific values To be able to calculate electrical characteristic values To be able to explain and design an example of indirect actuation To familiarise yourself with logic functions and to be able to design these


A-65


Positional sketch

Conveyor belt for packages

1. The piston rod of a cylinder is to advance automatically as soon as pushbutton S1 is actuated. 2. If the pushbutton is no longer actuated, the piston rod is to assume the retracted end position.

A-66



Exercise 7: Sorting of packages Name:

Date:

Fundamentals: Calculation of piston force

Sheet 1 of 3

The piston of a double-acting cylinder has a diameter of 16 mm and the piston rod a diameter of 8 mm. The frictional losses within the cylinder are 10 %. The following applies for double-acting cylinders: Advance stroke Return stroke

Feff Feff Feff A

=

(A • p) – FF (A' • p) – FF Effective piston force (N) Effective piston surface (m2) D2 • π ( ) 4 Effective annular surface (m2)

=

(D 2 − d 2 )

= = = = =

A'

p FF D d

= = = =

π

4 Working pressure (Pa) Friction force (approx. 10% of Fth ) (N) Cylinder diameter (m) Piston rod diameter (m)

– Calculate the effective piston force in the advance and return stroke at an operating pressure of 6 bar (600 kPa). To be calculated

Solution approach

Advance stroke

Return stroke


A-67



Date:

Fundamentals: Calculation of electrical characteristic values

Sheet 2 of 3

A relay in an electropneumatic circuit is designated as follows: 580 Ω, 1 W. – Calculate the permissible operating voltage which ensures that no overload occurs on the relay. To be calculated

Solution approach

Max. Operating voltage

A-68




Date:

Fundamentals:

Sheet 3 of 3

Triggering of the advancing movement of the piston rod of a cylinder is to be achieved by means of two pushbuttons S1 and S2. The valve coil 1M1 is energised if both pushbuttons are actuated simultaneously and the solenoid valve 1V1 switches into the actuated position causing the piston rod to advance. If at least one of the two pushbuttons is released, the valve switches into the initial position and the piston rod retracts. – Create an appropriate function table and the logic symbol. Note 0 means: Pushbutton not actuated, i.e. piston rod not advancing 1 means: Pushbutton actuated, i.e. piston rod advances S1

S2

1M1

1V1

Function table

Logic symbol


A-69



Date:


Sheet 1 vof 2

– Configure the pneumatic circuit diagram and design the electrical circuit diagram for the feeding device. 1A1

1V2

1V1

1B1

1

1

2

2

4

2

5

3

1M1

1B2

1V3

1M2 1


A-70




Date:


Sheet 2 of 2

+24 V

1

2

A1 K1

3

A1 K2

K3

A2 0V

5

4

1M1

1M2

A2

11

12 14

11

12 14

11

12 14

21

22 24

21

22 24

21

22 24

31

32 34

31

32 34

31

32 34

41

42 44

41

42 44

41

42 44



A-71



Date:


Sheet 1 of 1


Description

Equipment list

A-72


Exercise 8: Actuation of a sliding platform

Training aims

• To familiarise yourself with logic functions and to be able to design these • To be able to explain and design electrical latching circuits with dominant switchoff signal

Problem definition

Wooden boards are to be manually placed onto a sliding platform. The boards are to be pushed under a belt sanding machine by means of a pneumatic drive.

Parameters

• A double-acting cylinder is to be used. • The cylinder control is to be effected indirectly.

Project task

1. Answer the questions or carry out the exercises regarding the fundamentals of the training contents listed. 2. Design the pneumatic and electrical circuit diagrams. 3. Simulate the electropneumatic circuit diagram and check its correct functioning. 4. Compile the equipment list. 5. Carry out the pneumatic and electrical circuit assembly. 6. Check the circuit operation.


A-73


Positional sketch

Sliding platform

1. The piston rod of a cylinder is to advance if pushbutton S1 is actuated. 2. Actuation of pushbutton S2 is to cause the piston rod to retract.

A-74



Exercise 8: Actuation of a sliding platform Name:

Date:

Fundamentals: Signal storage

Sheet 1 of 3

The actuation of the pushbutton must be stored if the piston rod of a cylinder is to also advance if the pushbutton is only briefly actuated. This signal storage can be effected either in the power section or in the signal control section of a circuit. – Describe how signal storage is devised in the power section or in the signal control section respectively. Place of signal storage

Description: Signal storage

Signal storage in the power section

Signal storage in the signal control section


A-75



Date:

Fundamentals: Analysing circuits

Sheet 2 of 3

– Describe the behaviour of the circuit specified (pilot actuated, spring-return 5/2-way solenoid valve with manual override, double-acting cylinder) in the event of – Power failure – Pressure failure.

Power failure

A-76

Pressure failure




Date:

Fundamentals: Logic functions

Sheet 3 of 3

The lamp P1 is to be illuminated whenever pushbutton S1 is not actuated. – Draw up the appropriate function table and the logic symbol(s). 0 means: Pushbutton S1 not actuated, i.e. lamp P1 off 1 means: Pushbutton S1 actuated, i.e. P1 illuminated S1

P1

Function table

Logic symbol


A-77



Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the sliding platform.

4

5

2

1

3


A-78




Date:


Sheet 2 of 2

+24 V

2

1

3

A1 K1

1M1 A2

0V 11

12 14

21

22 24

31

32 34

41

42 44



A-79


Exercise 8: Actuation of a diverting device Name:

Date:


Sheet 1 of 1


Description

Equipment list

A-80


Exercise 9: Expanding a diverting device

Training aims

• To familiarise yourself with different types of end position control and to be able to select a suitable type. • To familiarise yourself with latching circuits of different characteristics.

Problem definition

Packages are to be transferred from one conveyor belt to another via a diverting device using reciprocating strokes. Once switched on, the device is to run continuously and only be switched off via a stop signal.

Parameters

• The latching circuit used is to exhibit a dominant „Off“ behaviour.

Project task

1. Answer the questions or carry out the exercises regarding the fundamentals of the training contents listed. 2. Design the pneumatic and electrical circuit diagram. 3. Simulate the electropneumatic circuit diagram and check its correct functioning. 4. Compile the equipment list. 5. Carry out the pneumatic and electrical circuit assembly. 6. Check the circuit operation.


A-81


Positional sketch

Diverting device for packages

1. Actuation of the pushbutton is to cause a reciprocating movement of the cylinder piston rod to drive the diverting device via a latching drive. 2. The packages are to be deflected and transported in the opposite direction. 3. Pressing of a second pushbutton is to switch off the drive.

A-82



Exercise 9: Expanding a diverting device Name:

Date:

Fundamentals: Latching circuits

Sheet 1 of 4

A latching relay circuit is required in order to store a signal in the signal control section. – The relay K1 is energised by actuating pushbutton S1. Complete the electrical circuit diagram below so that the relay latches after the pushbutton S1 is released. +24 V

1

13 S1 14

A1 K1 A2 0V 11

12 14

21

22 24

31

32 34

41

42 44



A-83



Date:


Sheet 2 of 4

An additional normally closed contact is required in order to cancel a set selflatching loop. Differentiation is made between two groups depending on the configuration of this normally closed contact: • Dominant setting self-latching loop • Dominant resetting self-latching loop – Complete the electrical circuit diagram below so that the self-latching loop is reliably cancelled via the actuation of a pushbutton S2. +24 V

1

13 S1 14

A1 K1 A2 0V 11

12 14

21

22 24

31

32 34

41

42 44


A-84




Date:


Sheet 3 of 4

The various circuits for signal storage exhibit different behaviour: • with simultaneously applicable set and reset conditions • in the event of power failure or cable fracture – Complete the table and enter the behaviour of the respective valve. Valve position unchanged/valve is actuated/valve switches to normal position Signal storage via double solenoid valve

Signal storage via electrical latching circuit combined with spring-return valve Dominant setting

Dominant resetting

Set and reset signal shared Power failure


A-85



Date:

Fundamentals: Limit switches and proximity sensors

Sheet 4 of 4

The function of limit switches and proximity sensors is to acquire information and to transmit this for signal processing. These include: Mechanical position switches (limit switches), magnetic proximity sensors (reed switches), optical proximity sensors, capacitive proximity sensors, inductive proximity sensors – Allocate the designations to the corresponding symbols in the table. Designation

Symbol BN BK

BU BN BK

BU BN BK

BU

4

2

1

BN BK

BU

A-86




Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagram for the diverting device. 1A1

1V2

1V1

1

1

2

2

4

2

5

3

1M1

1V3

1M2 1



A-87



Date:


Sheet 1 of 2

+24 V

1

2

13 S1

12

3

4

5

7

6

8

14

K1 14

11

31 S2 32

A1 K1

1M1

1M2

A2 0V 11

12 14

21

22 24

31

32 34

41

42 44


A-88




Date:


Sheet 1 of 1


Description

Equipment list


A-89


A-90


Exercise 10: Designing a stamping device

Training aims

• To be able to design a pressure-dependent reversal control. • To familiarise yourself with the design and mode of operation of magnetic proximity sensors.

Problem definition

Small mounting blocks are to be stamped during the production of door frames. These blocks are to be stamped by means of a stamping device.

Parameters

• The stamping pressure is to be 5.5 bar (550 kPa).

Project task



A-91


Positional sketch

Stamping device

1. The pressing of a pushbutton is to cause the stamping device to advance and the workpiece to be stamped. 2. The stamping tool is to return into the initial position once the stamping pressure is obtained.

A-92



Exercise 10: Designing a stamping device Name:

Date:

Fundamentals: Magnetic proximity sensor

Sheet 1 of 5

In contrast with limit switches proximity sensors are switched contactlessly and without an external mechanical actuating force. – Describe the design and function of a magnetic proximity sensor (reed switch). Description: Design and function

Symbol

Schematic representation

BN BK

BU


A-93



Date:

Fundamentals: Magnetic proximity sensors

Sheet 2 of 5

As regards polarity there are two different designs of electronic proximity sensors, i.e. PNP or NPN. – Describe the differences between these two types. PNP

A-94

NPN




Date:

Fundamentals: Pressure switches

Sheet 3 of 5

Pressure sensitive sensors, so-called PE converters, are used to monitor the pressure in a system. – Describe the mode of operation of PE converter. Description of mode of operation


A-95



Date:

Fundamentals: Pressure sensors

Sheet 4 of 5

Pressure sensors can be divided into two groups whereby differentiation is made between: • Pressure sensors with mechanical contact (mechanical principle of action) • Pressure sensors with electronic switching (electronic principle of action) – Describe the purpose and function of the pressure sensor shown below. Description: Purpose and function

A-96

Symbol

Schematic representation




Date:

Fundamentals: Choice of proximity sensors

Sheet 5 of 5

The end positions of a drive cylinder are to be sensed by means of proximity sensors. The following requirements apply regarding the proximity sensors: • The end positions of the piston rod are to be sensed contactlessly • The proximity sensors are to be insensitive to dust • The piston rod and trip cam of the cylinder are made of metal – Choose which proximity sensors meet the specified requirements and explain your reasons for this. Proximity sensor


Reason

A-97



Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the stamping device. 1A1

1V2

1V1

1

1

2

2

4

2

5

3

1M1

1V3

1M2 1


A-98




Date:


Sheet 1 of 2

+24 V

1

3

2

1B1

5

4

1B2

7

6

8

1B3 p

A1 K1

A1 K2

A2 0V

A1 K3

1M1

A2

1M2

A2

11

12 14

11

12 14

11

12 14

21

22 24

21

22 24

21

22 24

31

32 34

31

32 34

31

32 34

41

42 44

41

42 44

41

42 44



A-99



Date:


Sheet 1 of 1


Description

Equipment list

A-100


Exercise 11: Realising a pallet loading station

Training aims

• To familiarise yourself with displacement-step diagrams and to be able to design these for specified problem definitions. • To be able to realise a sequence control using two cylinders.

Problem definition

Stacks of roof tiles are to be strapped with a band and then transported to a pallet loading station, where they are to be transferred onto Euro pallets.

Parameters

• Adjust the one-way flow control valve so that both cylinders retract at identical speed.

Project task

1. 2. 3. 4. 5. 6. 7.

Design the displacement-step diagram. Draw up the corresponding function diagram and function chart. Design the pneumatic and electrical circuit diagrams. Simulate the electropneumatic circuit diagram and check its correct functioning. Compile an equipment list. Carry out the pneumatic and electrical circuit assembly. Check the circuit operation.


A-101


Positional sketch

Pallet loading station

1. Cylinder 1A1 is to advance when pushbutton S1 is pressed, whereby a single package arrives at the loading point and sensor 1B2 is actuated. 2. Cylinder 2A1 advances, actuates sensor 2B2, and pushes the package onto the pallet. 3. If 2B2 is actuated and S1 is unactuated, cylinder 1A1 retracts. 1B2 is therefore no longer actuated and cylinder 2A1 retracts. Consequently, the overall sequence is: 1A1+ 2A1+ 1A1– 2A1–

A-102



Exercise 11: Realising a pallet loading station Name:

Date:

Fundamentals: Designing the displacement-step diagram

Sheet 1 of 3

If pushbutton S1 is actuated, cylinder 1A1 advances whereby the package reaches its loading point and sensor 1B2 is actuated. Cylinder 2A1 advances, actuates sensor 2B2 and pushes the package onto the pallet. If 2B2 is actuated and S1 unactuated, cylinder 1A1 retracts. 1B2 is no longer actuated and cylinder 2A1 retracts. Consequently the overall sequence is: 1A1+ 2A1+ 1A1– 2A1– – Design the displacement-step diagram for the problem definition described.

1

2

3

4=1

1

1A1 0

1

2A1 0

Displacement-step diagram


A-103



Date:


Sheet 1 of 2

– Design the pneumatic and electrical circuit diagrams for the pallet loading station. 1A1

1V2

1V1

1

1

2

2

4

5

2A1

2

1

3

2V2

1V3

2

1 2V1

2

1

3


A-104




Date:


Sheet 2 of 2

+24 V

1

3

2

1B2 BN

5

4

6

7

8

2B2 BN BK

BK

BU

BU

A1

A1

A1

A2

A2

A2

1M1

0V 11

12 14

11

12 14

11

12 14

21

22 24

21

22 24

21

22 24

31

32 34

31

32 34

31

32 34

41

42 44

41

42 44

41

42 44

1M2

2M1



A-105



Date:


Sheet 1 of 1


Description

Equipment list

A-106


Exercise 12: Eliminating a fault on the pallet loading station

Training aims

• To be able to identify and eliminate faults in simple electropneumatic control systems.

Problem definition

The pallet loading station stops during continuous operation. A fault has occurred and must be eliminated. Thereafter the pallet loading station is to be re-started.

Parameters

• Only one fault has occurred.

Project task

1. Describe the behaviour of the control system. Compare this with the correct control system behaviour. Use the displacement-step diagram to assist you. 2. Localise potential causes of the fault with the help of the pneumatic and electrical circuit diagrams. 3. Find the fault in the control system and eliminate it. 4. Re-start the control system.


A-107


Positional sketch

Pallet loading station

1. Cylinder 1A1 is to advance if pushbutton S1 is pressed. This causes a single package to reach its loading point thereby actuating sensor 1B2. 2. Cylinder 2A1 advances, actuates sensor 2B2 and pushes the package onto the pallet. 3. If 2B2 is actuated and S1 unactuated, cylinder 1A1 retracts, 1B2 is no longer actuated and cylinder 2A1 retracts. Consequently the overall sequence is: 1A1+ 2A1+ 1A1– 2A1–

A-108



Exercise 12: Eliminating a fault on the pallet loading station Name:

Date:

Fault finding in simple electropneumatic circuits

Sheet 1 of 4

The following fault occurs in the circuit shown below: The piston rod of cylinder 1A1 and the piston rod of cylinder 2A1 advance and remain in the forward end position. – Describe what the potential causes of the fault could be. 1A1

1V2

1V1

2A1

1B2

1

1

2

2

4

2

5

3

1M1

1V3

2

1 2V1 1M2

1

2V2

2B2

2M1

2

1

3



A-109



Date:


Sheet 2 of 4

+24 V

1B2

1

3

2

BN

2B2

5

4

6

8

BN

BK

13

BK

S1

12

14

K3 14

BU

7

12

14

K2 11

12

14

K1 11

11

BU

A1 K1

A1 K2

A2 0V

A1 K3

1M1

A2

1M2

2M1

A2

11

12 14 .8

11

12 14 .7

11

12 14 .6

21

22 24

21

22 24

21

22 24

31

32 34

31

32 34

31

32 34

41

42 44

41

42 44

41

42 44


List of potential causes of faults

A-110




Date:


Sheet 3 of 4

A cable break occurs at the areas marked in the circuit shown below. – Describe what the effects of a cable break at these respective points are on the functioning of the circuit. +24 V

1B2

1

3

2

5

4

6

7

8

2B2 BN

BN BK

13

BK

S1

12

14 BU

14

K3

12

14

K2 11

12

14

K1 11

11

BU

A1 K1

A1 K2

A2 0V

A1 K3

1M1

A2

1M2

2M1

A2

11

12 14 .8

11

12 14 .7

11

12 14 .6

21

22 24

21

22 24

21

22 24

31

32 34

31

32 34

31

32 34

41

42 44

41

42 44

41

42 44



A-111



Date:


Sheet 4 of 4

Fault

Effect of fault

Break in earthing wire of relay K1 (current path 2)

Break in signal line of sensor 2B2 (current path 4)

Break in supply line of relay K3 (current path 5)

Break in supply line of relay contact 14 at K2 (current path 7) Break in earthing wire 2M1 (current path 8)

A-112




Date:

Fault finding: Determining the required status

Sheet 1 of 9

– Create the displacement-step diagram with the help of the documentation given out. Time

Components

Step 1 Designation

Identification

Signal

2

3

4

5

6

7

8

9

10



A-113


Exercise 12: Eliminating a fault in the pallet loading station Name:

Date:

Fault finding: Setpoint/actual comparison

Sheet 2 of 9

Determine the ACTUAL status of the system with the help of the following documentation: • Positional sketch with problem description • Graphic representation – If the correct function is not given (REFERENCE/ACTUAL comparison), clearly mark the area in the diagram where the fault occurs. Time

Components

Step 1 Designation

Identification

Signal

2

3

4

5

6

7

8

9

10


A-114




Date:

Fault finding: Description of faults

Sheet 3 of 9

You have marked the area where a fault occurs in the diagram of the worksheet ‘REFERENCE/ACTUAL comparison. – Describe the process up the point where the station or system stops. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________


A-115



Date:

Fault finding: Definition of faults - pneumatics

Sheet 4 of 9

Once you have established the ACTUAL status of the system, consider what the causes of the faults could be. In which pneumatic tubing connections could the fault occur? – Enter all the possibilities and indicate components at the start and end of the tubing connection in order to ensure clear identification. Potential fault No.

Tubing connection Start

End

Potential faults

A-116




Date:

Fault finding: Definition of faults – electrics

Sheet 5 of 9

Once you have established the ACTUAL status of the system, consider what the causes of the faults could be. • In which current paths could the fault be located? • What is the function of the current path? – Enter all the possibilities. Potential fault No.

Current path No.

Function of current path

Potential faults


A-117



Date:

Fault finding: Localisation of faults - pneumatics

Sheet 6 of 9

Investigate the potential causes of errors you have found in the pneumatics. • Use the same fault numbering that you have used for the worksheet ‘Definition of faults – pneumatic. • Document the procedure used to investigate the tubing connections. – Enter the results of your investigation. Measuring and test protocol Potential fault No.

Tubing connection Start

Inspection

Result

End

Measuring and test protocol

A-118




Date:

Fault finding: Localisation of faults

Sheet 7 of 9

Investigate the potential error causes you have found. • Use the same fault numbering that you have used in the worksheet ‘Definition of faults - electrics’. • Document the procedure you have used to check the line connection. – Enter the result of the investigation. Measuring and test protocol Potential fault No.

Current path No.

Measuring points

Inspection

Result

Measuring and test protocol


A-119



Date:

Fault finding: Elimination of fault

Sheet 8 of 9

Once you have localised the failure location, your procedure for the elimination of the fault must be documented on this worksheet. – Describe each of the steps carried out in detail. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________

Note In the event of the system not fulfilling the intended function return to the first worksheet and repeat the fault finding. Ask for new worksheet s to do so.

A-120




Date:

Fault finding: Re-starting

Sheet 9 of 9

Once you have identified, localised and eliminated the fault, re-start the system in accordance with the required status. Reset the specified required times. – Briefly document the procedure followed in note form. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________


A-121


A-122


Electro-pneumatics Seminar

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