Directional control valve

This example engineering drawing showing the hydraulic directional control valve usage with floating motor and pressure compensated pump is redesigned using the ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: DCV 17.jpg.
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"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow. ...
The spool (sliding type) consists of lands and grooves.The lands block oil flow through the valve body. The grooves allow oil or gas to flow around the spool and through the valve body. There are two fundamental positions of directional control valve namely normal position where valve returns on removal of actuating force and other is working position which is position of a valve when actuating force is applied. There is another class of valves with 3 or more position that can be spring centered with 2 working position and a normal position. ...
Directional control valves can be classified according to:
(1) number of ports;
(2) number of positions;
(3) actuating methods;
(4) type of spool." [Directional control valve. Wikipedia]
The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow. ...
While working with layouts of hydraulic machinery it is cumbersome to draw actual picture of every valve and other components.instead of pictures symbols are used for variety of components in the hydraulic system to highlight the functional aspects. symbol for directional control valve is made of number of square boxes adjacent to each other depending on the number of positions.connections to the valve are shown on these squares by capital letters.usually they are named only in their normal position and not repeated in other positions.actuation system of the valve is also designated in its symbol." [Directional control valve. Wikipedia]
The Mac template "Pneumatic 5-ported 3-position valve" for the ConceptDraw PRO diagramming and vector drawing software is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.
www.conceptdraw.com/ solution-park/ engineering-mechanical

"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow." [Directional control valve. Wikipedia]
This example engineering drawing showing the directional control valve usage with fixed volume pump and hydraulic cylinder is redesigned using the ConceptDraw PRO diagramming and vector drawing software from Wikimedia Commons file: DCV 19.jpg.
[commons.wikimedia.org/ wiki/ File:DCV_ 19.jpg]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
[creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

This sentence diagram example was redesigned from the Wikipedia file: Examples of Reed-Kellogg diagrams.jpg.
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This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. [creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
"Most methods of diagramming in pedagogy are based on the work of Alonzo Reed and Brainerd Kellogg in their book Higher Lessons in English, first published in 1877, though the method has been updated with recent understanding of grammar. Reed and Kellogg were preceded, and their work probably informed, by W. S. Clark, who published his "balloon" method of depicting grammar in his 1847 book A Practical Grammar: In Which Words, Phrases & Sentences are Classified According to Their Offices and Their Various Relationships to Each Another.
Some schoolteachers continue to use the Reed-Kellogg system in teaching grammar, but others have discouraged it in favor of more modern tree diagrams. However, these modern tree structures draw on techniques that were already present in Reed-Kellogg diagrams. Reed and Kellogg defend their system in the preface to their grammar:
The Objections to the Diagram. - The fact that the pictorial diagram groups the parts of a sentence according to their offices and relations, and not in the order of speech, has been spoken of as a fault. It is, on the contrary, a merit, for it teaches the pupil to look through the literary order and discover the logical order. He thus learns what the literary order really is, and sees that this may be varied indefinitely, so long as the logical relations are kept clear.
The assertion that correct diagrams can be made mechanically is not borne out by the facts. It is easier to avoid precision in oral analysis than in written. The diagram drives the pupil to a most searching examination of the sentence, brings him face to face with every difficulty, and compels a decision on every point.
These statements bear witness to the fact that Reed-Kellogg diagrams abstract away from actual word order in order to focus more intently on how words in sentences function and relate to each other." [Sentence diagram. Wikipedia]
The examples of Reed-Kellogg diagrams was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Language Learning solution from the Science and Education area of ConceptDraw Solution Park.

The vector stencils library "Switches and relays" contains 58 symbols of electrical contacts, switches, relays, circuit breakers, selectors, connectors, disconnect devices, switching circuits, current regulators, and thermostats for electrical devices.
"In electrical engineering, a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another.
The most familiar form of switch is a manually operated electromechanical device with one or more sets of electrical contacts, which are connected to external circuits. Each set of contacts can be in one of two states: either "closed" meaning the contacts are touching and electricity can flow between them, or "open", meaning the contacts are separated and the switch is nonconducting. The mechanism actuating the transition between these two states (open or closed) can be either a "toggle" (flip switch for continuous "on" or "off") or "momentary" (push-for "on" or push-for "off") type.
A switch may be directly manipulated by a human as a control signal to a system, such as a computer keyboard button, or to control power flow in a circuit, such as a light switch. Automatically operated switches can be used to control the motions of machines, for example, to indicate that a garage door has reached its full open position or that a machine tool is in a position to accept another workpiece. Switches may be operated by process variables such as pressure, temperature, flow, current, voltage, and force, acting as sensors in a process and used to automatically control a system. ... A switch that is operated by another electrical circuit is called a relay. Large switches may be remotely operated by a motor drive mechanism. Some switches are used to isolate electric power from a system, providing a visible point of isolation that can be padlocked if necessary to prevent accidental operation of a machine during maintenance, or to prevent electric shock." [Switch. Wikipedia]
"A relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a low-power signal (with complete electrical isolation between control and controlled circuits), or where several circuits must be controlled by one signal. The first relays were used in long distance telegraph circuits as amplifiers: they repeated the signal coming in from one circuit and re-transmitted it on another circuit. Relays were used extensively in telephone exchanges and early computers to perform logical operations.
A type of relay that can handle the high power required to directly control an electric motor or other loads is called a contactor. Solid-state relays control power circuits with no moving parts, instead using a semiconductor device to perform switching. Relays with calibrated operating characteristics and sometimes multiple operating coils are used to protect electrical circuits from overload or faults; in modern electric power systems these functions are performed by digital instruments still called "protective relays"." [Relay. Wikipedia]
The shapes example "Design elements - Switches and relays" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Electrical Engineering solution from the Engineering area of ConceptDraw Solution Park.

"Most methods of diagramming in pedagogy are based on the work of Alonzo Reed and Brainerd Kellogg in their book Higher Lessons in English, first published in 1877, though the method has been updated with recent understanding of grammar. ...
Some schoolteachers continue to use the Reed-Kellogg system in teaching grammar, but others have discouraged it in favor of more modern tree diagrams. However, these modern tree structures draw on techniques that were already present in Reed-Kellogg diagrams. Reed and Kellogg defend their system in the preface to their grammar:
The Objections to the Diagram.--The fact that the pictorial diagram groups the parts of a sentence according to their offices and relations, and not in the order of speech, has been spoken of as a fault. It is, on the contrary, a merit, for it teaches the pupil to look through the literary order and discover the logical order. He thus learns what the literary order really is, and sees that this may be varied indefinitely, so long as the logical relations are kept clear.
The assertion that correct diagrams can be made mechanically is not borne out by the facts. It is easier to avoid precision in oral analysis than in written. The diagram drives the pupil to a most searching examination of the sentence, brings him face to face with every difficulty, and compels a decision on every point.
... Reed-Kellogg diagrams abstract away from actual word order in order to focus more intently on how words in sentences function and relate to each other.
The Reed-Kellogg System. Simple sentences in the Reed-Kellogg system are diagrammed in accordance with the ... basic schemata" shown in this diagram example. [Sentence diagram. Wikipedia]
The example "The Reed-Kellogg system - Basic schemata" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Language Learning solution from the Science and Education area of ConceptDraw Solution Park.