Patent Application
20190094092
The disclosure relates to a pressure gauge, and more particularly to a diaphragm pressure gauge for measuring a pressure of a fluid.
Referring to
However, the diaphragm 121 made of an elastic metal material may get rusted and corroded due to direct contact with the detected fluid 10 that may be corrosive chemicals or a thickened and granular fluid. The diaphragm 121 and the screw 132 which directly contact the detected fluid 10 are liable to adhesion, corrosion and pollution by the fluid 10 and hence to shortening of the service life, which adversely affects the accuracy of the diaphragm pressure gauge 1.
Referring to
Therefore, an object of the disclosure is to provide a diaphragm pressure gauge that can alleviate at least one of the drawbacks of the prior art.
According to the disclosure, the diaphragm pressure gauge includes a cylinder, a pressure measuring unit and a pressure detecting assembly. The cylinder has a base and a cover connected to each other at peripheral walls thereof to define a cylindrical chamber. The pressure measuring unit is disposed in the cylinder, and has a first diaphragm, a second diaphragm spaced apart from the first diaphragm in a lengthwise direction, and a connecting rod operatively connected between the first and second diaphragms. The cylindrical chamber has a first subchamber which is defined by the base and the first diaphragm and which is configured for introduction of a fluid to be measured, a second subchamber which is defined by the first diaphragm and the second diaphragm, and a third subchamber which is defined by the second diaphragm and the cover. The first diaphragm includes a main diaphragm layer and a reinforcing layer. The main diaphragm layer has a first flange wall clamped between the peripheral walls of the base and the cover, and a first main diaphragm wall extending radially and inwardly from the first flange wall to divide the cylindrical chamber into the first and second subchambers. The reinforcing layer is attached to the first main diaphragm wall and is disposed in the second subchamber such that the first diaphragm is deformable to permit axial movement thereof in the lengthwise direction when subject to an internal pressure of the fluid introduced in the first subchamber. The connecting rod is disposed in the second subchamber and is actuated by the axial movement of the first diaphragm to move the second diaphragm. The pressure detecting assembly is disposed in the third subchamber to detect the movement of the second diaphragm so as to indicate the pressure of the fluid.
According to the disclosure, the diaphragm pressure gauge includes a cylinder, a pressure measuring unit and a pressure detecting assembly. The first diaphragm of the pressure measuring unit has a raised portion which projects in the lengthwise direction to be connected to the second diaphragm.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:
Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to
The cylinder 2 has a base 21 and a cover 22 which are connected to each other at peripheral walls 211, 221 thereof to define a cylindrical chamber 23. The base 21 has a surrounding wall 213 extending downwardly from the peripheral wall 211, and a base wall 212 extending radially and inwardly from the surrounding wall 213 to terminate at a central portion. The central portion is formed with a first channel 214 in spatial communication with the cylindrical chamber 23 for entry of the fluid 10 to be detected. The cover 22 has a surrounding wall 223 extending upwardly from the peripheral wall 221, and a cover wall 222 extending radially and inwardly from the surrounding wall 223.
The pressure measuring unit 3 is disposed in the cylinder 2, and has a first diaphragm 31, a second diaphragm 33 which is spaced apart from the first diaphragm 31 in a lengthwise direction, a rupture disc 32 which is disposed between the first and second diaphragms 31, 33, a connecting rod 34 which extends through the rupture disc 32 and which is operatively connected between the first and second diaphragms 31, 33, and an engaging ring 30 clamped between the second diaphragm 33 and the rupture disc 32. The cylindrical chamber 23 has a first subchamber 231 which is defined by the base wall 212 and the first diaphragm 31 and which is in spatial communication with the first channel 214 for introduction of the fluid 10, a second subchamber 232 which is defined by the first diaphragm 31 and the second diaphragm 33, and a third subchamber 233 which is defined by the second diaphragm 33 and the cover wall 222.
The first diaphragm 31 includes a main diaphragm layer 311 facing the first subchamber 231, and a reinforcing layer 312 facing the second subchamber 232. The main diaphragm layer 311 is made from an elastomeric material, such as rubber, plastic (e.g. Teflon), stainless steel, silicone, etc., and has a first flange wall 313 mounted on the peripheral wall 211 of the base 21, and a first main diaphragm wall 314 extending radially and inwardly from the first flange wall 313 to divide the cylindrical chamber 23 into the first and second subchambers 231, 232. The reinforcing layer 312 is mounted on or attached to the first main diaphragm wall 314 and in the second subchamber 232, and has a central layer portion 315 and a plurality of reinforcing ribs 316 each extending radially and outwardly from the central layer portion 315. With the aforesaid dual-layered structure, the structural strength of the first diaphragm 31 is increased. The reinforcing layer 312 may be integrally formed with the main diaphragm layer 311 by an injecting forming, for example. The rupture disc 32 is made of a rigid material, and has a flange 321 which is disposed between the peripheral walls 211, 221, and a main rupture wall 322 which is spaced apart from the reinforcing layer 312 to protect the first diaphragm 31 from excessive deformation. The main rupture wall 322 has a through hole 323 at a central portion thereof.
The second diaphragm 33 is made from an elastomeric material, such as plastic, metal (e.g. copper), etc., and has a second flange wall 331 in a fluid-tight engagement with the peripheral wall 221 of the cover 22, and a second main diaphragm wall 332 extending radially and inwardly from the second flange wall 331 to divide the cylindrical chamber 23 into the second and third subchambers 232, 233. The second main diaphragm wall 332 is of a wave shape.
The connecting rod 34 extends through the through hole 323 to have first and second rod ends connected to the first and second diaphragms 31, 33, respectively. In this embodiment, the first rod end abuts against and may be fastened to the central layer portion 315 of the first diaphragm 31, and the second rod end extends through the second diaphragm 33 and is connected with the pressure detecting assembly 4 such that the second diaphragm 33 is tightly engaged with the connecting rod 34 and the pressure detecting assembly 4.
The pressure detecting assembly 4 is disposed in the third subchamber 233 to detect movement of the second diaphragm 33 so as to indicate the pressure of the detected fluid 10. The pressure detecting assembly 4 may be of a known electronic or mechanical type to translate the movement of the second diaphragm 33 to a pressure signal. In this illustrated embodiment, the pressure detecting assembly 4 has a pressing sleeve 41 coupled with the second diaphragm 33 through the connecting rod 34, and a moving member 42 translating the movement of the pressing sleeve 41 to generate a torque that drives a pointer part to operate for indicating a value of the pressure of the detected fluid 10.
In use, the detected fluid 10 is introduced into the first subchamber 231 from the first channel 214 to have the internal pressure acting on the first diaphragm 31 so as to cause deformation of the first diaphragm 31. With the connection of the connecting rod 34 with the first diaphragm 31 having the reinforcing layer 312 including the central layer portion 315 and the reinforcing ribs 316, the first diaphragm 31 is axially moved in the lengthwise direction to precisely drive the movement of the second diaphragm 33 and the pressing sleeve 41 so as to actuate the pressure detecting assembly 4 to indicate a detected pressure.
In this embodiment, the second diaphragm 33 transmitting the displacement thereof to the pressure detecting assembly 4 to generate a pressure indication does not contact the detected fluid 10 to avoid adhesion and pollution. The first diaphragm 31 with the dual-layered structure has great structural strength and stability and can be prevented from corrosion. Moreover, with the connecting rod 34 bracing and connected between the first and second diaphragms 31, 33, and with the pressing sleeve 41 aligned with the connecting rod 34 in the lengthwise direction, a pressing force generated as a result of the pressure of the fluid 10 can be magnified to ensure the preciseness of the measuring of the pressure gauge, and to enlarge the pressure detecting scope of the pressure gauge.
In this embodiment, the second diaphragm 33 is of a disc shape. Since the second diaphragm 33 according to the disclosure is not required to be in air-tight engagement with the cylinder 2, referring to
Referring to
Referring to
In use, a fluid (A) of a detected object 10 enters the first subchamber 231 through the first channel 214, and another fluid (B) with a smaller internal pressure than that of the fluid (A) enters the differential pressure region 234 through the second channel 353. The difference in pressures of the fluids (A) and (B) results in the displacement of the connecting rod 34 and the second diaphragm 33 so as to measure the pressure drop. The fluids (A) and (B) flow into the first subchamber 231 and the differential pressure region 234, respectively, and do not contact the second diaphragm 33 so as to prevent the second diaphragm 33 from adhesion and pollution.
Referring to
As illustrated above, with the structure that the pressure measuring unit 3 is clamped between the base 21 and the cover 22, the base 21 and the cover 22 can be made in a modular manner. The rupture disc 32 and the spacer disc 35 can be selectively assembled in the cylinder 2 to use the pressure gauge as a general pressure gauge or a differential pressure gauge.
Referring to
Referring to
In the previous embodiments, the pressure detecting assembly 4 is made with a mechanical design. As described above in the eleventh and twelfth embodiments, the pressure gauge may be connected with a digital pressure indicator to indicate mechanically and digitally the measured pressure, or for monitoring purposes. Moreover, the load cell 43 may be connected with a solenoid operated in response to the measured pressure to generate an alarm mark for monitoring a system employing the pressure gauge. The load cell 43 may be connected with a pressure relief valve to control or limit the pressure in a system in response to the measured pressure.
While the disclosure has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
