JPS6247063Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an eccentric indicator pressure gauge that provides normal pointer action even under conditions of use such as plunger pumps where pressure changes are severe, and prevents wear caused by vibration.

In conventional pressure gauges, the deformation amount of the Bourdon tube is mechanically expanded through a gear group at the tip of the Bourdon tube, which is deformed by receiving pressure, and the displacement is converted into the rotational direction. It is designed to directly implement the guidelines supported by . Therefore, in places where the pressure changes rapidly and constantly fluctuates, the pointer will also constantly vibrate. For example, in a plunger pump or the like, the pressure changes with each operation of a pump driven by a motor, and usually changes several hundred to a thousand times per minute. When a conventional C-type Bourdon tube type pressure gauge is installed in a pressure source where such severe pressure changes occur, this pressure change is magnified through the Bourdon tube through gears, etc., and is directly transmitted to the pointer, so the pointer is almost at pressure. It vibrates according to the number of changes. This pointer fluctuates violently, several hundred times or more per minute, and due to the synergistic effect of the afterimage phenomenon in the eye, the pointer vibrates so violently that it becomes like a wide plate between the maximum and minimum amplitudes. It becomes difficult to read the value clearly and accurately using the pointer, and the pointer and other pivoting parts become severely worn, which significantly shortens the life of the pressure gauge.

In view of this, the present invention changes the shape of the Bourdon tube from a C-shape to a spring-like shape, thereby increasing the amount of displacement of the Bourdon tube compared to a C-shaped Bourdon tube. Then, the displacement is further enlarged, and a magnet is provided to face each of the link and the pointer provided on the dial side, and the attraction force of these two magnets is used to transmit the Bourdon tube displacement to the pointer side. This is an attempt to eliminate the above-mentioned drawbacks.

The present invention will be described below based on embodiments shown in the drawings.

In the figure, reference numeral 1 denotes a pressure gauge stock connected to a pressure source, and a Bourdon tube 2 is provided on the stock 1.
The bourdon tube 2 and the stock 1 are joined by a conventional method, such as soldering, and the bourdon tube 2
is formed by winding a flat tube around the outer periphery of the axis, that is, in the shape of a spring with concentrically different diameters. At this time, the winding yield of the Bourdon tube is determined by applying a preset maximum pressure for measurement to a minimum pressure, the tip of the Bourdon tube is displaced and the pointer is directly swung at a predetermined interval. Therefore, if you want to increase the amplitude of the pointer, increase the winding capacity of the Bourdon tube. Even if the tip of the Bourdon tube applies the same pressure, the amplitude of the pointer will change more than a Bourdon tube with a smaller (shorter) winding capacity. can be made larger.

At the tip of the Bourdon tube, which is the spring-shaped center, a support 3 is installed on the central axis of the Bourdon tube, that is, in a direction protruding toward the Bourdon tube side. . A link 4 of a required length is provided on this column 3 so as to be parallel to the spiral-shaped Bourdon tube, and a permanent magnet 5 is integrally provided on one side of the tip of this link by welding, gluing, or the like. Further, the stock 1 is provided with a scale plate 6, and a pointer 8 is rotatably fitted into a pointer shaft 7 embedded in the scale plate 6, and this pointer 8 is also equipped with a permanent magnet 9.
The magnet 9 of the pointer 8 and the magnet 5 of the link 4 face each other, and the magnet 8 of the pointer is placed on the trajectory of the magnet 5 that moves with the displacement of the Bourdon tube. The setting position of the pointer shaft and the setting position of the magnet on the pointer shall be determined so that it moves while being attracted. Incidentally, the scale plate 6 is provided with an arc-shaped notched window hole along the movement locus of the magnet provided in the link due to the displacement of the Bourdon tube, so that the pointer can be set without weakening the attraction force between the magnets 5 and 8. Regulation to prevent swinging beyond the maximum allowable range. It is also possible to provide a direct link at the tip of the center of the Bourdon tube and attach a magnet to the link.

According to the eccentric indicating pressure gauge of the present invention, when pressure is applied to the Bourdon tube through the stock, a force acts on the Bourdon tube shaped like a spring in response to the pressure, and this force causes the Bourdon tube to stretch. As a result, the central tip of the Bourdon tube rotates. That is, when the Bourdon tube is displaced, the column 3 rotates, the link 4 swings about the column, and the amount of displacement of the Bourdon tube is further expanded by the link. Therefore, when the magnet provided on the link moves due to the swing of the link, the pointer-side magnet, which is always attracted to this magnet, also moves via its magnetic force, thereby moving the pointer. At this time, the change in the Bourdon tube is detected by moving the pointer through magnetic force, so the pressure constantly fluctuates violently like a plunger pump, and when this pressure fluctuation is applied to the Bourdon tube, the tip of the Bourdon tube link also vibrates according to the number of pressure fluctuations. do. However, since the magnets on the pointer side and the link side are far apart, and the vibration of the link is transmitted to the pointer side via magnetic force, the vibration on the link side is absorbed, and the displacement of the Bourdon tube is controlled without the pointer vibrating. Transmitted and accurate pressure can be indicated.

When the Bourdon tube and the link vibrate due to severe pressure fluctuations, the magnet provided at the end of the link vibrates in the same way between the amplitudes of the link ends. However, due to the intense vibrations, the attraction force of the link-side magnet acts on the vibration width of the end of the link on average.
For example, the magnet diameter at the end of the link is 3 mm, and the vibration width is 6.
mm, the attraction force by this magnet acts equally on a width of approximately 6 mm. For this reason, the magnet provided on the pointer side is made to stop and be attracted to a fixed position with almost no vibration. Therefore, even if the pressure source applied to the Bourdon tube undergoes severe pressure fluctuations, the pointer can be displayed almost stationary.

In addition, the magnet is inserted into an arc-shaped cutout hole provided in the scale plate along the movement trajectory of the magnet on the pointer side, and the maximum allowable range of the pointer is regulated by this hole.Therefore, even if a large pressure change causes the Bourdon tube and link to oscillate beyond a predetermined angle, the weight of the magnet will not cause the pointer to turn back, and the pointer will always be held in the predetermined position.

Furthermore, by changing the mounting position of the magnet on the pointer side or the link side, manufacturing errors in the Bourdon tube link can be easily absorbed.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing only the main parts of the eccentric indicating pressure gauge excluding the outer casing, and FIG. 2 is a plan view of the Bourdon tube. 1 is a stock, 2 is a Bourdon tube, 3 is a column, 4 is a link, 5 and 9 are permanent magnets, 6 is a scale plate, 7 is a pointer shaft, and 8 is a pointer.

Claims (1)

[Scope of utility model registration request] One end of the Bourdon tube, which is made by winding flat tubes concentrically into a spring-like shape with different diameters, is fixed to a stock, a link of the required length is protruded from a support provided at the tip of the center side, and a section of the tip of this link is attached. A magnet is provided on the side, and a magnet is also provided on the pointer so as to face this magnet.
The pointer is swingably supported by a pointer shaft embedded in a scale plate, and an arc-shaped notch window hole is bored in the scale plate along the locus of motion of both of the opposing magnets, thereby controlling the displacement of the Bourdon tube. The pressure is transmitted through the magnetic force of both magnets to stably display the eccentric pressure gauge.