RU2350791C1 - Pneumatic timing unit - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: unit consists of cylinder, of piston with rod installed in cylinder with forming piston and of rod cavities each having supplying channel. Also apertures are made in the cylinder along its generatrix; the rod cavity is conjugated with the input of a corresponding jet discrete mono-stable element "negative-OR" via each of apertures. The second input of each element "negative-OR" is connected with a timing unit; while the output of each element "negative-OR" is connected with corresponding input of the jet discrete mono-stable multi-input element "OR". The output of the element "OR" is tied with switching input of the trigger with separate inputs; the output of the trigger with separate inputs on which the signal of the unit level is set at entry of the signal of the unit level from the output of the element "OR" is connected with the supplying channel of the rod cavity, while the second output of the trigger with separate inputs is connected with the supplying channel of the piston cavity.

EFFECT: simplification of design, upgraded reliability, expanded functions.

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Description

The invention relates to technical means of automation and can be used in pneumatic automatic control systems.

Known pneumatic software devices in which the formation of control signals (commands) is performed using a program carrier made in the form of a punch card and connected to the cylinder rod ("Pneumatics and hydraulics. Drives and control systems". Issue 6. Edited by E.V. Herz , M.: Mechanical Engineering, 1979, p.168).

Known devices in which control signals are generated using a number of sensors mounted on a moving body and acting, for example, on a fixed contact (copyright certificate No. 1826637, class F15B 15/28, "hydraulic cylinder with position indication", bull. No. 20 from 07/20/95), or with the help of one moving limit switch, which is affected by stops pre-installed in predetermined positions (copyright certificate No. 339907, class G05В 19/44, “Hydraulic software device”, bulletin No. 17 of 01.01.72 )

The disadvantage of these devices is their complexity.

Closest to the proposed invention in terms of features is a cylinder with a piston extreme position sensor containing a cylinder and a piston with a rod mounted in the cylinder, with the formation of a piston and rod cavities, each of which has a supply channel (copyright certificate No. 1180565, class F15В 15 / 28, “Cylinder with a sensor for extreme positions of the piston”, Bulletin No. 35 of 09/23/85).

The disadvantage of this device is the ability to obtain information only about the extreme positions of the piston.

The technical result of the proposed technical solution is to simplify the design, increase reliability and expand the functionality of the device.

The specified technical result is achieved by the fact that in the pneumatic programming device comprising a cylinder and a piston with a rod installed in the cylinder, with the formation of the rod and piston cavities, each of which has a supply channel, holes are made in the cylinder along its generatrix, through each of which the rod the cavity communicates with the input of the corresponding jet discrete monostable element OR NOT, the second input of each discrete monostable element OR NOT connected with the program setting device, and the output of each of the elements is NOT connected with the corresponding input of the discrete monostable multi-input multi-input element OR, the output of the multi-input element OR is connected to the switching input of the trigger with separate inputs, the output of the trigger with separate inputs, the signal of the unit level at which the signal of the unit level the output of the OR element is connected to the supply channel of the rod cavity, and the second trigger output with separate inputs is connected to the supply channel of the piston cavity, and in Ora switching trigger input to separate inputs serves to supply a control signal to the extension rod, and adjusting the input latch with separate inputs serves to feed to the initial installation of the device in a starting position signal.

Introduction to the device of inkjet elements with appropriate connections increases reliability and simplifies the design, because, firstly, the control process is carried out only with the help of inkjet elements that do not have moving parts, and secondly, position sensors do not participate in the control, the role of which is Monostable Inkjet Logic Elements OR NOT. The expansion of functionality is due to the fact that the stroke size can be adjusted in a wide range with discreteness limited only by the design features of the cylinder and the characteristics of the inkjet elements OR NOT. As an elemental base, for example, VOLGA series inkjet elements can be used (see "Inkjet logic elements and automatic control devices for technological equipment.” Industry Catalog. Edited by E.I. Chaplygin, Moscow: VNIITEMR, 1989) .

The drawing shows a pneumatic software device.

The device includes a cylinder 1, a piston 2 with a rod installed in the cylinder 1 with the formation of the rod cavity 3 and the piston cavity 4. The piston cavity 4 has a supply channel 5, and the rod cavity 3 has a supply channel 6. The supply channel 5 communicates with the output 7 trigger with separate inputs 8, and the input channel 6 communicates with the output 9 of the trigger with separate inputs 8. Input 10 of the trigger with separate inputs 8 is connected to the output 11 of the discrete multi-input element OR 12. The outputs of the digital discrete elements OR-NOT 13 are connected to the input the ladders of the OR element 12. One of the inputs of each OR-NOT 13 element is connected to the program setting device 14, and the second input of each OR-NOT 13 element communicates through the corresponding hole 15 with the rod cavity 3 of cylinder 1. Input 16 of the trigger with separate inputs 8 serves to supply a control signal to the extension of the rod, and the installation input 17 of the trigger with separate inputs 8 serves to give a command for the initial installation of the device (piston) in the initial position.

Pneumatic software device operates as follows.

After supplying the supply medium (compressed air), a short-term unit level signal (setup signal) is supplied to the device at the installation input 16, a unit-level signal is set at the output 9 of the trigger with separate inputs 8, and compressed air enters the rod cavity 3 through the supply channel 6. If the piston was not in its original position, the rod will retract. At the same time, at the inputs of the elements OR-NOT 13 connected to the rod cavity 3 through the holes 15, signals of a single level will be established. At the inputs of the elements 13 associated with the program setting device 14, there are also unit level signals, with the exception of the input of the element corresponding to the required stop position when extending the rod. Suppose you want to stop the piston in the i-position. In this case, at the input of the corresponding element, OR NOT from the device for setting program 14, a signal of zero level is received, with the help of which a stop command will be generated in the i-position.

Position programming can be done manually, for example, using pneumatic toggle switches. In this case, the program setting device 14 includes a set of pneumatic toggle switches (one for each position). If during the cycle it is required to stop the piston with the rod 2 in different positions, the program setting device 14 may include, for example, a shift register, from which zero-level signals are sent to the corresponding elements of OR-NOT 13 in various clock cycles.

After applying the control signal of a single level to input 16, a trigger with separate inputs 8 will switch, output 7 will set the signal to a single level, and output 9 to a signal of zero level. Through the supply channel 5, the compressed air will enter the piston cavity, and the extension of the rod will begin. The working medium (air) displaced by the piston enters the input of each of the elements OR NOT 13. Thus, when the rod is extended at the input of each of the elements 13 associated with the rod cavity 3, a signal of a unit level is stored.

When the piston reaches the i-position at the input of the corresponding OR-NOT 13 element, a zero level signal appears and a unit level signal is generated at the output of this element (since the second level input from the program setting device also receives a zero level signal). This signal is fed to the input of OR element 12. Element 12 will switch, and at its output 11 there will be a unit level signal, which will be fed to input 10 of the trigger with counting input 8. Trigger 8 will switch, output 9 will be set to a single level signal, and at output 7 - signal of zero level. Compressed air through the inlet channel 6 will enter the rod cavity, and the piston with the rod will begin to move to its original position.

After the piston leaves the i-position, a unit level signal is set at the input of the corresponding element OR NOT, and a zero level signal is set at input 10 of the trigger with separate inputs 8. The device is ready to be turned on again.

Pneumatic software device has great functionality due to a wide range of piston stroke control. Only inkjet elements are involved in the control process. The exclusion from the control process of devices with moving parts and position sensors simplifies the design and increases the reliability of the pneumatic software device. The function of the position sensors in this device is performed by inkjet discrete monostable elements OR-NOT.

Claims (1)

A pneumatic software device comprising a cylinder, a piston with a rod installed in the cylinder with the formation of a piston and rod cavities, each of which has an inlet channel, characterized in that holes are made in the cylinder along its generatrix, through each of which the rod cavity communicates with the input of the corresponding a jet discrete monostable element OR NOT, the second input of each discrete monostable element OR NOT connected to the program setting device, and the output of each of the elements OR NOT connected to the corresponding input of a discrete monostable, multi-input OR element, the output of the multi-input element OR is connected to the switching input of the trigger with separate inputs, the output of the trigger with separate inputs, the signal of the unit level at which is set when the signal of the unit level comes from the output of the OR element, is connected to the supply channel rod cavity, and the second trigger output with separate inputs is connected to the supply channel of the piston cavity, the second switching trigger input with separate inputs serves to supply a control signal to the extension of the rod, and the installation input of the trigger with separate inputs serves to supply a signal to the initial installation of the device in its original position.