Pressure indicator

FIELD: measuring engineering.

SUBSTANCE: housing (1) of the pressure indicator receives bellows (2) connected to core (6) provided with bushing (7) having solenoid (8) which forms inductive converter (9) with core (6). Housing (1) is provided with time relay (15) made of air vessel (16), sensitive member (18) with inductive pickup (19) made of winding (11) and additional core (20) spring-loaded by spring (26), adjustable throttle (22), and stop (25). Before operation, bellows (2) and object (4) are pressurized. In so doing, bellows (2) with bushing (7) moves upward and additional core (20) of pickup (19) enters winding (11), thus signaling of attainment of working pressure. Ring air chamber (13) is then pressurized. In so doing, solenoid (9) is secured to winding (11) interconnected through spacer (10). Relay (15) is pressurized simultaneously. When pressure in bellows (2) drops, core (6) begins to move, thus, generating a signal.

EFFECT: expanded functional capabilities and enhanced reliability.

1 cl, 2 dwg

The invention relates to instrumentation, and more specifically to devices for measuring pressure mainly in the control of tightness.

Known detector pressure, comprising a housing defined therein a diaphragm and a spring, the displacement transducer into an electrical signal in the form of a solenoid mounted on the sleeve, a ferromagnetic core that is associated with a membrane which is interoperable with the lower part of the solenoid, a friction element containing an annular chamber, the cavity of which communicates with the pressure source through the normally closed valve (Ed. mon. The USSR №1675706, CL 01 L 19/08, 19/10, 1991).

The disadvantage of this detector pressure is limited technological capabilities only alarm pressure drop, since the device does not allow to determine the level of working pressure and to fix the duration of the tests that you want to control the tightness. In addition, the device has low reliability due to the direct contact of the annular chamber with the moving solenoid, which leads to rapid wear.

The closest technical solution is the pressure detector (RF Patent No. 2156967, CL G 01 L 19/08, 2000), comprising a housing installed on the displacement transducer into an electrical signal in the form of the of olenoid, mounted on the sleeve, and a ferromagnetic core located with the opportunity to interact with the solenoid, a friction element containing an annular pnevmochamber, the cavity of which communicates with the pressure source, additional ferromagnetic core, spring, time relay, which consists of a pneumatic capacity in the form of glass, limited sensing element mounted on the case and the sensor of the sensing element.

Here expanded technological capabilities of the device. This result is achieved by controlling the operating pressure and set the relay time, which provides more control, including gives you the ability to directly control the amount of gas leakage over time, characterizing the integrity of the test object.

However, the technological capabilities of such devices are limited in accuracy and range control gas leakage due to the small stroke and non-linearity of the deflection of the membrane, moving under the influence of the operating pressure, that is, the membrane can provide only a narrow control range corresponding to its displacement. As the upper part of the solenoid is used to communicate with the core service of the sensor, and its lower part is the core of the displacement transducer, and between what artecnica is spring, this leads to a significant increase in the size and weight of the solenoid, and a significant number of its coils, which are unused as in the work of the service of the sensor, and the displacement transducer. This reduces the precision characteristics of the sensor and the Converter, and therefore, the whole device. Use time relay spring rheostat transducer as a sensor sensitive element, and a retaining spring of the sensing element, makes it difficult to configure the relay time and limits its ability to range settings. In addition, the device of the three transducers move complicates its design and reduces reliability in General. The implementation of the friction element when it comes with a set of spring-loaded plungers located between the solenoid and ring pnevmoskleros, complicates its design. This reduces the reliability of fixing of a solenoid and sleeve, as significantly reduces the contact area between the surface and the friction element. Here, the contact area is replaced by a dot by the number of plungers. In General, all these disadvantages reduce technological capabilities and reliability of the entire device.

The technical result of the invention consists in the expansion of technological POS of the values by improving the accuracy and sensitivity of the device when the control gas leakage; accurate job working pressure and time control, as well as expansion of the range control; the ability to measure the amount of gas leakage in the facility; to improve the reliability by reducing the design of the device number of converters move, simplify the configuration of the relay time and ensure fixation of the solenoid winding of the friction element by increasing the contact area.

This technical result is achieved by the fact that the known detector pressure, comprising a housing defined therein a displacement transducer into an electrical signal in the form of a solenoid mounted on the sleeve, and a ferromagnetic core located with the opportunity to interact with the solenoid, a friction element containing an annular pnevmochamber, the cavity of which communicates with the pressure source, additional ferromagnetic core, spring, time relay, which consists of a pneumatic capacity in the form of glass, limited sensing element mounted on the case and the sensor sensitive element according to the invention is equipped with a bellows, one end of which is fixed on the housing and on the other - fixed ferromagnetic core, and the bellows is connected with the pressure source, the sensor sensing element made in the form of inductively what about the Converter, winding which is installed on the upper part of the sleeve with the ability to interact with additional ferromagnetic core, associated with the sensing element, in this case between the winding and the sleeve solenoid posted by strip, and they are fastened together with the ability to interact with a friction element, and a spring placed between the gasket and the loose end of the additional ferromagnetic core, a glass fitted with an emphasis made with the possibility of adjusting the position of the sensing element installed between the body and the glass.

In addition, the friction element is equipped with a flexible tube, the ends of which the perimeter is fixed on the chassis, placed between the ring pnevmoskleros and solenoid and coil with the possibility of frictional engagement with the latter in operating position, the ring pnevmostartery.

The differences between the claimed pressure detector is its embodiment in which it is supplied by a bellows connected with the source of operating pressure, one end of the bellows is fixed to the body, and the other pinned ferromagnetic core, can significantly increase the moving core in the solenoid in the control process, using the whole length of the solenoid and makes it move uniform, which increases the the effectiveness and sensitivity of the device, allows not only to control but also to measure the amount of gas leakage in the object. In addition, increasing the working pressure range that can be used in this detector pressure, thereby expanding its technological capabilities.

The implementation of the sensor of the sensing element in the form of an inductive transducer coil which is installed on the upper part of the sleeve with the ability to interact with additional ferromagnetic core, associated with the sensing element, simplifies the design of the device, since the sensor is sensitive element in addition to the function of issuing completion signal time delay, i.e. on completion of the leak test, is also used to control the level of the working pressure, which is installed in the detector, the height of the winding for receiving signals is used, which increases the accuracy and sensitivity of the sensor.

Supply of glass fence, made with the possibility of adjusting the position of the sensing element installed between the body and the glass, simplifies the setting of the time relay, which increases the reliability of the design of the device as a whole.

The fastening between a winding, gaskets, and bushings with solenoid interoperable with a friction element that allows them to combine the temporary fixation of the latter and extends the possible location area of the friction element on the device.

Placing a spring between the strip and the free end of the additional ferromagnetic core provides the necessary for the operation of the time relay apparatus of the sensing element, it performs the function of back pressure. In addition, the spring presses the extra core to stop fixing it, when the sensor performs a control function specified operating pressure.

An embodiment of the friction element with which it is equipped with a flexible tube, the ends of which the perimeter is fixed on the chassis, placed between the ring pnevmoskleros and solenoid and coil with the possibility of frictional engagement with the latter in operating position, the ring pnevmostartery allows flexible tube to perform the function of easily replaceable tread, which eliminates direct contact of the ring pnevmostartery and the surface of the solenoid, as well as winding, thus reducing its wear and tear. In addition, the flexible tube provides a large area of frictional contact than ring pneumonia, improving the fixation unit of the winding and bushing solenoid, thereby increasing the reliability of the device as a whole.

The essence of the invention is illustrated by drawings of the design of the detector pressure.

Figure 1 shows the design of the pressure detector,the General view in the context of the schema and connected to a source of compressed air; figure 2 - design of the friction element with the elastic tube.

The pressure detector (figure 1) consists of a housing 1, in the cavity of which a bellows 2, calculated at the desired working pressure range. One of the ends of the bellows 2 is fixed by means of the cover 3 to the housing 1. The cavity of the housing 1 And is communicated with the atmosphere and the cavity B of the bellows 2 - with the test object 4, in which pressure is created by a compressed air source (not shown) and is clipped on the test valve 5. On the second end of the bellows 2 is fixed ferromagnetic core 6 on which are mounted with a gap sleeve 7, is equipped with a solenoid 8. The housing 1, the ferromagnetic core 6 and the solenoid 8 to form an inductive transducer 9 move into an electrical signal. On the upper part of the sleeve 7 is installed, the gasket 10 and coaxially with the solenoid 8, the winding 11, which are fastened together (e.g., glue) and have a uniform outer surface 12 coated with a layer of solid dielectric. Sleeve 7 solenoid 8 and the winding 11 are frictional connection with the body 1 by means of the friction element is made in the form of an annular pnevmostartery 13, located in the bore of the housing 1, which may be a friction to interact with the outer surface 12. Pneumonia 13 connected with a source of pneumatic pressure (not shown) via normal for the ryty valve 14, which ensures the connection with the atmosphere at the beginning of the test. On the housing 1 is relay 15 time, which consists of a pneumatic tank 16, formed by the Cup 17 and the sensor element 18 made, for example, in the form of a membrane and the sensor 19 sensor element 18. Moreover, the sensing element 18 is installed between the housing 1 and the glass 17. The sensor 19 is made in the form of an inductive transducer and consists of winding 11 and the additional ferromagnetic core 20, rigidly connected with the sensing element 18 by means of washers 21, and a screw connection (not shown) and having the opportunity to interact with the coil 11. Pneumatic tank 16 through an adjustable throttle 22 and the valve element 23 is connected to a source of pneumatic pressure (not shown), and through the exhaust valve 24 is connected to the atmosphere. Meanwhile the glass 17 is equipped with an adjustable stop 25. Moving and fixing the latter is carried out by means of a screw connection, which ensures the adjustment of the initial position of the sensing element 18 and the additional core 20 between the free end of which strip 10 posted by spring 26. It is made of a nonmagnetic material and calibrated to the magnitude of the pneumatic pressure supplied to the relay 15 time. In addition, we are roena adjusting the initial position and the working of the sensing element 18 and the additional core 20 may be implemented through a set of pads 27, installed between the housing 1 and the glass 17, followed by fastening bolts (not shown). All this allows you to more accurately set the relay 15 time in the sensor 19 to the corresponding control parameters.

The friction element (2) can be equipped with a flexible tube 28, the ends of which the perimeter is fixed in grooves of the housing 1. Thus, the flexible tube 28 is placed between the ring pnevmoskleros 13 and the solenoid 8 and the winding 11 with the possibility of frictional engagement with their outer surface 12 in the working position of the ring pnevmostartery 13. Elastic tube 28 prevents the ring pnevmochamber 13 from damage and reduces its wear. In addition, the flexible tube 28 increases the efficiency of the friction element due to the fact that its deflection from the effects of the ring pnevmostartery 13 under pressure, provides a large area of frictional contact with the surface 12 of the solenoid 8 and the winding 11.

The pressure detector (figure 1) works as follows.

When you control the tightness of the cavity B of the bellows 2 and the test object 4 connects through the channel in the lid 3 with a source of pneumatic pressure (not shown). The bellows 2 under the action of pressure in the cavity B is stretched and moves the core 6 and the sleeve 7, the solenoid 8, the gasket 10, the winding 11. the providing of air in the cavity And prevents this movement, as she communicated with the atmosphere. Additional core 20 is in the winding 11, and the sensor 19 sensor element 18 detects the pressure increase in the cavity B. at the same time additional core 20 compresses the spring 26, which creates on the sensing element 18 a certain back pressure necessary for operation of the relay 15 time. And ring pneumonia 13 does not prevent the movement of the solenoid 8 and the winding 11, which is carried out up until the sensor 19 will not fix the desired working pressure in the cavity B of the bellows 2. When the sensor 19 produces a signal to the valve 5 and the normally closed valve 14, which feeds compressed air into the annular paumacasino 13. This provides a cutoff cavity B and the object 4 from a source of pneumatic pressure, and the fixing sleeve 7, the solenoid 8 and the winding 11 through arisen frictional connection between the outer surface 12 and annular pnevmoskleros 13. Thus, the inductive transducer 9 move the bellows 2 into an electrical signal provisioned. At the same time is the start relay 15 time, pre-configured for the desired exposure time control. The configuration is done through a set of pads 27, an adjustable stop 25 and the adjustable throttle 22, which sets the flow rate is ozdoba, therefore, the filling speed pneumatic tank 16. This enables the valve element 23 and turns off the exhaust valve 24. The sensing element 18 under the action of air pressure, pneumatic filling the tank 16 of the Cup 17 will deform and move bonded with him by washers 21 additional core 20. Filling speed pneumatic tank 16 is proportional to a given time, therefore, the deformation of the sensing element 18 and the corresponding additional amount of movement of the core 20 in the winding 11 will be proportional to the exposure time. The inductance of the winding 11 is proportional to put into it the additional weight of the core 20, indicating the exposure time. After a predetermined time control on the output of the sensor 19 will receive the appropriate signal. If the time control will be a pressure drop in the cavity B due to leakage of the test object 4, the bellows 2 will be compressed. Moreover, the compression of the bellows 2 will be proportional to the magnitude of the pressure drop and, consequently, the magnitude of the leak. When the core 6 is withdrawn from the stationary solenoid 8. Output inductive transducer 9 will receive the electrical signal, the magnitude of the leakage of compressed air from the test object 4 Upon completion of the inspection, the pressure in cavity B occurs when disconnecting the test object 4, when the bellows 2 is compressed to its original position. Simultaneously ring pneumonia 13 is connected through the valve 14 to the atmosphere and its frictional connection with the outer surface 12 is broken, the sleeve 7, the solenoid 8, the gasket 10 and the coil 11 under the action of its own weight together with the core 6 and the bellows 2 is returned to its original position.

The pressure in the pneumatic tank 16 is in its cut-off from the source of pneumatic pressure through the valve element 23 and the message through the exhaust valve 24 with the atmosphere. Under the action of the spring 26 additional core 20 and the sensing element 18 is moved to its original position until it touches the washer 21 with an adjustable stop 25.

If the friction element (2) equipped with a flexible tube 28, in the initial position, when in the ring pnevmochamber 13 is not supplied with compressed air, it is in the grooves of the housing 1 and prevents movement of the sleeve 7, the solenoid 8 and the winding 11. After a signal on the fixation of compressed air through the normally closed valve 14 enters the ring pnevmochamber 13. It expands and prohibit loose in the housing 1 part of the elastic tube 28. Thus there is a frictional connection between the caved surface of the elastic tube 28 and the outer surface 12 of the solenoid 8 and the winding 11 than PR is by fixing them. When the signal on the termination of the fixation ring pneumonia 13 through the valve 14 is connected with the atmosphere, and the pressure on the elastic tube 28 is terminated. While it due to elastic deformation of the elastic material returns to its original position in the slots of the housing 1, and its frictional connection with the outer surface 12 of the solenoid 8 and the winding 11 is terminated.

The use of the proposed detector pressure compared to existing to enhance the technological capabilities due to the fact that the device is provided with a bellows, which is fixed to the ferromagnetic core of displacement transducer into an electrical signal. Application in the design of the bellows allows you to get significantly large displacement of the core in the solenoid and thus to significantly improve the sensitivity and accuracy of the control of leakage of the proposed detector pressure compared to similar devices, provided with a membrane. In addition, it allows you to use the detector pressure over a wider range of working pressure and with appropriate calibration of the inductive displacement transducer for measuring the nominal value of the leak pressure drop. The use of a pressure switch with an inductive displacement transducer chuvstvitelno the element increases performance and improves the reliability of the detector pressure by simplifying its design by using only two transducers move, because the sensor of the sensing element also performs the monitoring function of the specified operating pressure. In addition, simplified setup time relay, and expanded the range of its settings through the use of inductive transducer sensing element and an adjustable stop. Additionally, the proposed detector pressure increased reliability due to use in a friction element of the elastic tube, which increases the area of the frictional connection and therefore its effectiveness. In addition, this design of the friction element eliminates the direct contact between the surface of the ring pnevmostartery and the outer surface of the solenoid winding without the use of a set of movable spring-loaded mechanical plungers, as in the known constructions, thus reducing wear pnevmostartery. The placement of the elastic tube in the slots on the chassis to mount on the perimeter makes the design of the device is workable, because it extends the possible placement of the ring pnevmostartery in the housing, and the tube is much easier to mount and dismantle compared with a set of mechanical plungers.

1. The pressure detector, comprising a housing defined therein a displacement transducer into an electrical signal in the form of a solenoid mounted on the sleeve, and romagnano core, located with the opportunity to interact with the solenoid, a friction element containing an annular pnevmochamber, the cavity of which communicates with the pressure source, additional ferromagnetic core, spring, time relay, which consists of a pneumatic capacity in the form of glass, limited sensing element mounted on the case and the sensor of the sensing element, characterized in that it is provided with a bellows, one end of which is fixed on the housing, and the other pinned ferromagnetic core, and the bellows is connected with the pressure source, the sensor sensing element made in the form of an inductive transducer, a coil which is installed on the upper part of the sleeve interoperable with additional ferromagnetic core, associated with the sensing element, in this case between the winding and the sleeve solenoid posted by laying and they are fastened together with the ability to interact with a friction element, and a spring placed between the gasket and loose face additional ferromagnetic core, a glass fitted with an emphasis made with the possibility of adjusting the position of the sensing element installed between the body and the glass.

2. The pressure detector according to claim 1, characterized in that the friction e is ement equipped with a flexible tube, the ends of which the perimeter is fixed on the chassis, placed between the ring pnevmoskleros and solenoid and coil with the possibility of frictional engagement with the latter in operating position, the ring pnevmostartery.