JPH0640830U - Pressure gauge - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a pressure gauge that can measure the pressure of liquid such as cement milk and fresh concrete during pumping for a long period of time, has a simple structure to reduce the cost, and is easy to maintain. To aim. [Structure] A case formed by penetrating the inside to form a pressure sensing chamber, a pressure gauge main body provided with a sensing unit at an opening at one end of the case facing the pressure sensing chamber, and the other end of the case. A structure including an inlet provided in the opening, a piston housed in the pressure sensitive chamber and slidably closing the inlet, and a liquid filled between the piston of the pressure sensitive chamber and the sensing unit.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pressure gauge for measuring the pressure of a fluid, particularly a pressure gauge for measuring pressure during pumping of cement milk, fresh concrete, etc., which contains a large amount of impurities.

[0002]

[Prior art]

 When measuring the pressure of a fluid such as water or oil, a pressure gauge such as what is generally called a water pressure gauge is used. These pressure gauges measure the pressure by directly contacting the diaphragm, which is the sensing section, with the fluid to be measured. However, when the fluid to be measured is water or oil, there is no problem, but when measuring the pressure during the pumping of a fluid containing impurities, the diaphragm of the pressure gauge is severely damaged and it cannot be put to practical use. Therefore, as shown in FIG. 4, an attempt was made to mount a jig between the fluid to be measured 1 and the diaphragm 2 with the oil 3 and the rubber plate 4 interposed therebetween.

[0003]

[Problems to be solved by the device]

 Even if the conventional structure with relatively high strength as shown in Fig. 4 is set to measure the pressure during pumping of fresh concrete, which is the field of use of the present invention, the flow of impurities including pebbles, etc. The surface of the rubber plate cannot withstand, and the rubber plate breaks in a short time, making measurement impossible. If the rubber plate breaks, the fresh concrete will also immediately damage the diaphragm, so there was a practical problem that maintenance could not be performed. Therefore, the present invention aims to provide a pressure gauge that can measure the pressure of cement milk, fresh concrete, etc. during fluid pressure feeding for a long period of time, has a simple structure to reduce the cost, and is easy to maintain. .

[0004]

[Means for Solving the Problems]

 A case formed by penetrating the inside to form a pressure-sensitive chamber, a pressure gauge provided with a sensing unit at one end opening of the case facing the pressure-sensitive chamber, and a pressure gauge at the other end opening of the case. The inlet is provided, a piston which is housed in the pressure-sensitive chamber and slidably closes the inlet, and a fluid filled between the piston of the pressure-sensitive chamber and the sensing portion.

[0005]

[Action]

 Install the inlet so that it faces the fluid to be measured. The fluid to be measured presses one end surface of the piston through the inlet. Then, the piston moves and pressurizes the fluid in the pressure sensing chamber. As a result, the sensing section of the pressure gauge body receives pressure indirectly and can measure.

[0006]

【Example】

 The present invention will be described below with reference to an embodiment shown in FIGS. In the figure, 11 is a cylindrical metal case. A pressure sensitive chamber 12 is formed inside the case 11. A screw portion 10 is screwed on the inner surface of the upper end opening of the case 11, and a pressure gauge main body 14 with a diaphragm (sensing portion) 13 facing the pressure sensing chamber 12 is screwed on and off automatically. . Further, an inlet port 15 is provided at the lower end opening of the case 11 so that the outside of the case 11 and the pressure sensing chamber 12 communicate with each other. Reference numeral 16 denotes a metal piston slidably housed in the pressure sensing chamber 12. The piston 16 is prevented from coming off from the introduction port 15 by a stopper 17 provided at the bottom of the case 11, and the introduction port 15 is always closed. The air vent hole 18 that communicates with the pressure sensing chamber 12 from the side surface of the case 11 is normally closed by a cap 19 in a detachable manner. The air vent hole 18 is for releasing the air that enters the pressure sensitive chamber 12 during assembly. A fluid, for example, a relatively viscous oil 20 is filled between the diaphragm 13 and the piston 16 of the pressure sensing chamber 12. Reference numeral 21 denotes a mounting screw threaded on the upper end surface of the piston 16, which is used when the piston 16 is taken out from the pressure sensing chamber 12 by screwing a long screw.

A case where the pressure of the fresh concrete 23 pumped in the pipe 22 as shown in FIG. After attaching the lower end surface of the case 11 to the hole formed in the upper surface of the pipe 22 so as to be liquid-tightly fixed by, for example, welding, the following operation is performed. The fresh concrete 23, which is pumped in the pipe 22 at a predetermined pressure, presses the lower surface of the piston 16 from the inlet 15. Then, the piston 16 is pushed upward (shown by the dotted line in FIG. 1), and the diaphragm 13 is pressed through the oil 20. As a result, the pressure gauge body 14 outputs a pressure signal to a predetermined measuring device (not shown).

In the above embodiment, the stopper 17 is provided in the case 11 to prevent the piston 16 from falling, but the piston 16 itself may be provided with a catching portion to prevent the piston 16 from falling. Further, the shape and structure of the pressure gauge body 14 are not limited to those in the above embodiment, and it is needless to say that various kinds can be adopted.

[0009]

[Effect of device]

 It is quite conceivable that impurities such as pebbles contained in the fresh concrete 23 as described above rub or hit the lower surface of the piston 16. However, since the piston 16 is made of a metal material, it can withstand the above-mentioned symptoms without any trouble and can continuously perform the function of accurate pressure transmission. In addition, since there are no minute parts and the structure is extremely simple, it can be manufactured at low cost, and because there are no parts that wear rapidly, maintenance is extremely easy. Further, even if a problem such as oil loss occurs, the piston 16 protects the diaphragm 13, so that the pressure gauge body 14 is not damaged.

[Brief description of drawings]

FIG. 1 is an operation explanatory view showing an embodiment of the present invention.

FIG. 2 is an external view of the embodiment of the present invention with the pressure gauge body removed.

FIG. 3 is a sectional view showing an embodiment of the present invention with a pressure gauge body removed.

FIG. 4 is an explanatory diagram showing a conventional example.

[Explanation of symbols]

 11 Case 12 Pressure Sensitive Chamber 13 Sensing Part 14 Pressure Gauge Main Body 15 Inlet 16 Piston 20 Fluid

Claims (1)

[Scope of utility model registration request] A case formed by penetrating the inside to form a pressure-sensitive chamber, a pressure gauge main body provided with a sensing portion at one end opening of the case facing the pressure-sensitive chamber, and an opening at the other end of the case. It is characterized by comprising an introduction port provided, a piston housed in the pressure sensing chamber and slidably closing the introduction port, and a fluid filled between the piston of the pressure sensing chamber and the sensing section. Pressure gauge.