SIMPLE PNEUMATIC CIRCUIT EXERCISES
Direct control of a pneumatic cylinder
The simplest level of control for the single or double acting cylinder involves direct control signals. Direct control is used where the flow rate required to operate the cylinder is relatively small, and the size of the control valve is also small with low actuating forces. If the valve is too large, the operating forces required may be too great for direct manual operation.
Exercise 1: Direct control of a single acting cylinder
The Problem
A single acting cylinder of 25mm diameter is to clamp a component when a push-button is pressed. As long as the push-button is activated, the cylinder is to remain in the clamped position. If the push-button is released, the clamp is to retract.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
c) Describe the operation of the circuit.
FIG. Exercise 1
Exercise 2: Direct control of a double acting cylinder
The Problem
A double acting cylinder is to extend when a push-button is operated. Upon release of the push-button the cylinder is to retract. The cylinder is of small bore (25mm diameter) requiring a small flow rate to operate at the correct speed.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
Exercise 3 : Indirect control of a single acting cylinder
The Problem
A large diameter single acting cylinder is to extend upon operation of a push-button valve. The push-button valve is situated at a remote position. Therefore indirect control should be used to operate the cylinder. The cylinder is to retract once the remote push-button is released.
FIG. Exercise 3
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
c) Describe the operation of the circuit.
d) Explain why the remote positioning of a valve is advantageous
Exercise 4: Indirect control of a double acting cylinder
The Problem
A double acting cylinder is to extend when a push-button is operated. Upon release of the push-button the cylinder is to retract. The cylinder is 250mm diameter and consumes a large volume of air.
FIG. Exercise 4
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 5: The logic AND function; the two pressure valve
The Problem
A transfer station removes a product from a conveyor belt. If the product is detected as present and if the operator presses the push-button, the pick-up cylinder 1.0 extends. The product is sensed by a 3/2 way roller lever valve. Upon the release of the push-button the cylinder 1.0 is to retract to the initial position.
FIG. Exercise 5
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 6: The logic OR function; the shuttle valve
The Problem
A cylinder is used to transfer parts from a magazine. If either a push button or a foot pedal is operated, then the cylinder is to be extended. Once the cylinder is fully extended, it is to retract to the original position. A 3/2 way roller lever valve is to be used to detect the full extension of the cylinder.
FIG. Exercise 6
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 7: Memory circuit and speed control of a cylinder
The Problem
A double acting cylinder pushes products from a magazine onto a chute. The cylinder is to extend fully when a push-button is operated. The cylinder is not to retract until full extension is reached. Extension is confirmed by a roller lever valve. The cylinder is to continue forward even if the push-button is released before full extension is reached. The speed of the cylinder is to be adjustable in both directions
of motion.
FIG. Exercise 7
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
Questions
1. What is the switching status of the memory valve when first fitted to the system and therefore what position will the cylinder be in?
2. Describe the operation of the circuit.
3. If the push-button is held operated even after full extension is reached, what effect will this have on the cylinder retraction?
4. What is the effect on the operation of fitting the roller lever valve at the mid-stroke position of the cylinder, i.e. not at the full extension position?
Exercise 8: The time delay valve
The Problem
A double acting cylinder is used to press together glued components. Upon operation of a push-button, the clamping cylinder extends and trips a roller lever valve. Once the fully extended position is reached, the cylinder is to remain for a time of T=6 seconds and then immediately retract to the initial position. A new start cycle is only possible after the cylinder has fully retracted. The cylinder extension is to be slow and the retraction adjustable but relatively fast.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
SIMPLE PNEUMATIC CIRCUIT EXERCISES
Direct control of a pneumatic cylinder
The simplest level of control for the single or double acting cylinder involves direct control signals. Direct control is used where the flow rate required to operate the cylinder is relatively small, and the size of the control valve is also small with low actuating forces. If the valve is too large, the operating forces required may be too great for direct manual operation.
Exercise 1: Direct control of a single acting cylinder
The Problem
A single acting cylinder of 25mm diameter is to clamp a component when a push-button is pressed. As long as the push-button is activated, the cylinder is to remain in the clamped position. If the push-button is released, the clamp is to retract.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
c) Describe the operation of the circuit.
FIG. Exercise 1
Exercise 2: Direct control of a double acting cylinder
The Problem
A double acting cylinder is to extend when a push-button is operated. Upon release of the push-button the cylinder is to retract. The cylinder is of small bore (25mm diameter) requiring a small flow rate to operate at the correct speed.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
Exercise 3 : Indirect control of a single acting cylinder
The Problem
A large diameter single acting cylinder is to extend upon operation of a push-button valve. The push-button valve is situated at a remote position. Therefore indirect control should be used to operate the cylinder. The cylinder is to retract once the remote push-button is released.
FIG. Exercise 3
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicate the numbering system for the connections (ports).
c) Describe the operation of the circuit.
d) Explain why the remote positioning of a valve is advantageous
Exercise 4: Indirect control of a double acting cylinder
The Problem
A double acting cylinder is to extend when a push-button is operated. Upon release of the push-button the cylinder is to retract. The cylinder is 250mm diameter and consumes a large volume of air.
FIG. Exercise 4
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 5: The logic AND function; the two pressure valve
The Problem
A transfer station removes a product from a conveyor belt. If the product is detected as present and if the operator presses the push-button, the pick-up cylinder 1.0 extends. The product is sensed by a 3/2 way roller lever valve. Upon the release of the push-button the cylinder 1.0 is to retract to the initial position.
FIG. Exercise 5
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 6: The logic OR function; the shuttle valve
The Problem
A cylinder is used to transfer parts from a magazine. If either a push button or a foot pedal is operated, then the cylinder is to be extended. Once the cylinder is fully extended, it is to retract to the original position. A 3/2 way roller lever valve is to be used to detect the full extension of the cylinder.
FIG. Exercise 6
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.
Exercise 7: Memory circuit and speed control of a cylinder
The Problem
A double acting cylinder pushes products from a magazine onto a chute. The cylinder is to extend fully when a push-button is operated. The cylinder is not to retract until full extension is reached. Extension is confirmed by a roller lever valve. The cylinder is to continue forward even if the push-button is released before full extension is reached. The speed of the cylinder is to be adjustable in both directions
of motion.
FIG. Exercise 7
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
Questions
1. What is the switching status of the memory valve when first fitted to the system and therefore what position will the cylinder be in?
2. Describe the operation of the circuit.
3. If the push-button is held operated even after full extension is reached, what effect will this have on the cylinder retraction?
4. What is the effect on the operation of fitting the roller lever valve at the mid-stroke position of the cylinder, i.e. not at the full extension position?
Exercise 8: The time delay valve
The Problem
A double acting cylinder is used to press together glued components. Upon operation of a push-button, the clamping cylinder extends and trips a roller lever valve. Once the fully extended position is reached, the cylinder is to remain for a time of T=6 seconds and then immediately retract to the initial position. A new start cycle is only possible after the cylinder has fully retracted. The cylinder extension is to be slow and the retraction adjustable but relatively fast.
Exercise
a) Draw the circuit diagram for the problem.
b) Designate the valves and indicated the numbering system for the connections.
c) Describe the operation of the circuit.