JPS5935792Y2 - Damper device for pressure sensor - Google Patents

Description

[Detailed description of the invention] This invention uses a damper interposed between a fluid pressure source such as a lubricating oil pump for an internal combustion engine and a pressure sensor such as an oil pressure gauge, so that the pressure pulsations in the fluid pressure source are directly reflected in the pressure. This invention relates to a damper device for a pressure sensor that prevents the pressure from being transmitted to the sensor side.

FIG. 1 shows a conventional example of this type of damper device, which consists of a lubricating oil pump 3 for supplying lubricating oil to an internal combustion engine 1 and a hydraulic pressure gauge 5 for indicating its oil pressure. A case is shown in which a needle valve type damper 4 is interposed between them.

This damper 4 forms a seat portion 32 between the pump-side port 11 and the pressure sensor-side port 12, and uses a minute gap 33 between the seat portion 32 and the needle valve 31 as a constriction portion for the lubricating oil pump 3. The pressure pulsations on the side are prevented from being directly transmitted to the oil pressure gauge 5 side.

However, in the damper of this conventional structure, the valve shaft 30
The opening degree of the gap 33 changes greatly due to the minute movement of the gap 33,
Not only is adjustment relatively difficult, but the opening degree of the gap 33 changes greatly due to corrosion and wear of the needle valve 31, and the oil pressure gauge 5
This may cause the pressure sensor to operate incorrectly, or in extreme cases may damage the pressure sensor.

This invention was made to improve the above problems,
Adjustment is made by screwing and fixing a screw shaft with a male thread into the screw hole of the main body with a female thread, and using the spiral gap formed between the female and male screws as a constriction part in the damper. It is easy to use, and there is little change in drawing degree due to corrosion or wear.
Another object of the present invention is to provide a damper device that can maintain a good pressure pulsation damping effect over a long period of time.

Hereinafter, the damper device for the pressure sensor of the present invention will be explained using the internal combustion engine lubrication system shown in FIG. 2 as an example. In FIG. 4 indicates a damper, and 5 indicates an oil pressure gauge.

The main body 6 of the damper 4 has an opening 11 connected to the lubricating oil pump side (hereinafter referred to as the pressure source side opening), an opening 12 connected to the oil pressure gauge 5 side (hereinafter referred to as the sensor side opening), and
It has a screw hole 13 formed between both openings 11,12.

The damper 4 is formed by screwing a screw shaft 7 into a screw hole 13 of the main body 6.

The screw shaft 7 has a main body part 14.15' at both ends thereof, and a small diameter shaft part 20, 21.22 and a small diameter thread part 16, 1 are arranged between them.
1-Alternately forming I~.

Male threads 14a having the same pitch as the female threads 13a of the screw hole 13 are provided on the outer peripheries of the main body portion 14° 15 and the small diameter threaded portions 16,17.

15a, 16a, and 17a are formed, among which a male thread 16a of a small diameter threaded portion 16.17.

17a has its top portion removed to reduce its outer diameter.

As a result, the male threads 16a, 17 of the small diameter threaded portions 16.17
Spiral gaps 16b and 17b are formed between the screw hole 13a and the female thread 13a of the screw hole 13.

In this embodiment, the male screws 14a and 15a formed in the main body portions 14 and 15 located at both ends of the screw shaft T correspond to male screws at both ends as defined in the claims of the utility model registration.

Further, when the screw shaft 7 is screwed into the screw hole 13 of the main body 6, the male screws 14a and 15a formed on the main body portion 14. It is screwed and fixed in a screwed state.

Therefore, by removing the tops of the intermediate male screws 16a, 17a as described above, the contact area between the intermediate male screws 16a, 17a and the female screw 13a is reduced (in other words, the area of contact between the female screw 13a and the intermediate male screw 13a is reduced). Despite the fact that the self-locking force acting between the screws 16a and 17a is reduced, the relative position (axial position) between the main body 6 and the threaded rod I is maintained over a long period of time. It turns out.

A shaft hole 18 reaching the inside of the small diameter shaft portion 20 is formed at one end of the screw shaft 7, and a shaft hole 24 reaching the inside of the small diameter shaft portion 22 is formed at the other end. are in communication with the outer periphery of the small diameter shaft portion 20 or the outer periphery of the small diameter shaft portion 22 through the horizontal hole 19 or 23, respectively.

Therefore, in FIG. 2, the discharge side of the lubricating oil pump 3 includes the opening 11 of the damper 4, the shaft hole 18, the horizontal hole 19, the outer periphery of the small diameter shaft part 20, the spiral slit 16b1, the outer periphery of the small diameter shaft part 21, and the spiral Slit 17b1 Small diameter shaft portion 22 outer periphery, horizontal hole 23, shaft hole 2
4. It will communicate with the oil pressure gauge 5 through the opening 12,
The pulsation of the pressure on the lubricating oil pump 3 side is attenuated in the passage in the damper 4, particularly in the spiral IWs 416b and 17b, and is transmitted to the oil pressure gauge 5.

The spiral gaps 16b and 17b in the damper 4 are
It is always maintained at a constant length, and even if the screw shaft 7 moves back and forth within the screw hole 13, the passage length does not change. Even if the outer surface is slightly corroded or worn, the effect of damping pressure pulsations remains almost unchanged.

Further, as described above, the relative position in the axial direction between the main body 6 and the screw shaft 7 is changed by the tightening force between the female screw 13a of the main body 6 and the male screws 14a and 15a at both ends formed on the main body portion 14.15 of the screw shaft 70. For example, the screw shaft 7
is pulled out below the initial setting position and comes into contact with the pipe end of the lubricating oil pump 3 connected to the opening 11, thereby changing the opening area of the shaft hole 18 formed in the screw shaft 7. Therefore, the pressure pulsation damping characteristics of the lubricating oil by the damper 4 are maintained satisfactorily over a long period of time.

Furthermore, since the main body 6 and the screw shaft 7 are fixed by the tightening force between the female screw 13a of the main body 6 and the male screws 14a and 15a at both ends of the screw shaft 7 (in other words, the intermediate male screw of the screw shaft 7 The screws 16a and 17a hardly contribute to the fixation of the main body 6 and the screw shaft 7), and the diameter of the small diameter threaded portion 16, 17 can be adjusted without worrying about the tightening force between the main body 6 and the screw shaft 7. By arbitrarily changing the dimensions and increasing or decreasing the thickness of the narrow gaps 16b and 17b, dampers with different pressure pulsation damping characteristics can be easily formed.

In the illustrated embodiment, the fluid pressure source is a lubricating oil pump,
Although a hydraulic pressure gauge is used as the pressure sensor, in other embodiments of the present invention, other fluid pressure equipment, such as a cooling water pump, an air compressor, a refrigerator compressor, etc., may be used as the fluid pressure source. , other measuring instruments or control devices, such as water pressure gauges, gas pressure gauges, pressure switches, etc., can be employed as the pressure sensor.

The present invention has a spiral slit 16b in the damper 4 as described above.
, 17b is formed and this is used as a constriction part to prevent pressure pulsation from propagating to the pressure sensor side, so there is almost no need to adjust the degree of constriction, and moreover, the inner surface of the screw hole 13 of the damper body 6 Even if the outer surface of the screw shaft T that is screwed into the screw hole 13 is corroded or worn, it has almost no effect on the pressure pulsation damping effect of the damper 4, and the normal operation of the pressure sensor is always ensured. This has the effect of protecting itself from abnormal pressure.

Further, the damper device of the present invention securely connects the main body 6 and the screw shaft 7 by the tightening force acting between the female screw 13a of the screw hole 13 of the main body 6 and the male screws 14a and 15a at both ends of the screw shaft 7. Since it is configured so that it can be fixed, relative displacement in the axial direction between the main body 6 and the screw shaft 7 can be prevented, and the pressure pulsation damping effect of the damper 4 can be maintained well over a long period of time. The diameter of the intermediate male threads 16a, 17a of the screw shaft 7 which form the slits 16b, 17be, which act as constricted parts between the female thread 13a of the hole 13, is changed appropriately to adjust the size of the slits 16b, 17b. There is also the effect that dampers 4 having different pressure pulsation damping characteristics can be formed by changing the pressure pulsation damping characteristics without impairing the mutual tightening force between the main body 6 and the screw shaft 7.

[Brief explanation of the drawing]

FIG. 1 is a schematic view of a damper device for a conventional pressure sensor, and FIG. 2 is a schematic view of a damper device for a pressure sensor according to an embodiment of the present invention. 3... Lubricating oil pump, 4... Damper, 5... Oil pressure gauge, 6... Damper body, 7... Screw shaft, 11.
12...Damper body opening, 13...Screw hole, 13
a... Female thread, 16a, 17a = male thread, 16b,
17b...Spiral slit.

Claims (1)

[Claims for Utility Model Registration] A main body 6 having a pair of openings 11.12 and a threaded hole 13 communicating with both openings 11.12, and a spiral slit 16b with respect to the female thread 13a of the threaded hole 13. , 17b, which can be screwed together and have male threads at both ends 14a, 1.
The screw shaft 7 has an intermediate male thread 16a, 17ae having a smaller outer diameter than that of 5a, and the both ends of the screw shaft 7 have male threads 14a. 15a is screwed into the screw hole 13, the pair of openings 11.12 forms the spiral slit 16b. One opening 11 and the other opening 12 of the pair of openings of the damper 4 are configured to communicate with each other via 17b.
a fluid pressure source such as a lubricating oil pump 3 and a hydraulic pressure gauge 5, respectively.
A damper device for a pressure hinger, characterized in that it is connected to a pressure sensor such as.