JPS62151703A - Measuring instrument for abrasion quantity of seal material for piston - Google Patents

Abstract

PURPOSE:To measure the quantity of abrasion of a seal material like a rider ring by providing a detecting element which outputs a detection signal corresponding to the deviation between a cylinder and a piston. CONSTITUTION:A thin discoid member 19 to be detected is fixed to the nut 13 of the piston. Then, concentric circular projections N1-N4 which project toward a cylinder head 20 in parallel to the axis of the member to be detected and annular grooves M1-M4 at their outer peripheries are formed on the front surface. An end part 23 of an optical fiber 22 which is aligned is fixed to the head 20. The lower parts of rider rings 16 and 17 increase in the quantity of abrasion with time. Consequently, light passed through an optical fiber element wire 22a from the end part 23 is shifted to illuminate the bottom of the groove M1 from the end surface of the projection N1 and the light is supplied to a photodetecting element 25 through an element wire 22b. At this time, the quantity of light of the element 25 decreases below that when none of the rider rings wears and the element wire 22b faces the projection N1. The quantity of abrasion of the seal material is measured from this decrease in the quantity.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a piston that moves in a cylinder, and the piston is provided with an annular sealing material that is in airtight contact with the inner circumferential surface of the cylinder. Relates to a device for measuring the amount of wear of sealing materials for pistons in compression (compression and internal combustion) applications.

BACKGROUND TECHNOLOGY A reciprocating pressure heddle is used to forcefully transport vaporized gas of liquefied natural gas. In this reciprocating compression rock, a piston moves back and forth within a cylinder, and evaporated gas is compressed and supplied. In order to achieve airtightness between the outer circumferential surface of the piston and the inner circumferential surface of the cylinder during such compression, a rider ring is fitted into the piston, and the rider ring contacts the inner circumferential surface of the cylinder. .

Intermediate points to be solved by the invention In such prior art, rP is not used in the operation of reciprocating type compression
The rider ring will wear out. If the amount of wear on the rider ring becomes excessive, an accident may occur in which the piston and cylinder come into contact with each other during operation. The amount of wear on the rider ring can suddenly increase due to changes in the operating conditions 7+1-. In VT, I'm like this J7 brother.''
11. Since no measures have been taken to determine this, and only periodic changes of the rider ring are carried out, the contact failure described in iiQ may occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus for measuring the amount of wear of a seal material for a piston, which is capable of measuring the amount of wear of a seal material such as a rider ring.

Means for Solving the Problems The present invention provides an apparatus for measuring wear amount of a sealing material for a piston, in which a piston reciprocates within a cylinder, and the piston is provided with an annular sealing material that airtightly contacts the inner peripheral surface of the cylinder. , a detection element that is provided on the cylinder or piston and that derives a detection signal corresponding to the misalignment of the axes between the cylinder and the piston, and means that measures the wear rate of the seal material in response to the output from the detection element. 1 is a wear amount measuring device for a piston sealing material, characterized in that:

According to the present invention, a detection signal corresponding to a thin line misalignment between the cylinder and the piston can be derived by the detection element provided on the cylinder or the piston. When sealing materials such as rider rings wear out,
The axes of the ring and piston are misaligned. Therefore, the wear amount of the sealing material can be measured by the wear amount measuring means that responds to the output from the detection element.

Embodiment FIG. 1 is a sectional view of a reciprocating compressor according to a one-day embodiment of the present invention. This compression allowance is used to compress and supply evaporated gas of liquefied natural gas.

A piston 2 reciprocates within the cylinder 1.

This evaporated gas is clean and does not contain dust.

The reciprocating motion of the piston 2 compresses the evaporated gas from the suction port 3 and sends it under pressure through the discharge port 4. One end of a piston rod 5 is fixed to the piston 2. The other end of the piston rod 5 is connected to a connecting rod 7 by a pin 6. The connecting rod 7 is connected to a crank arm 9 by a crank pin 8. The crank arm 9 is rotationally driven by a drive shaft having a thin wire 10.

FIG. 2 is an enlarged sectional view of the piston 2. FIG. Pin6)n2
, the receiving part 11 protruding outward of the piston rod 5, and the washer 1.
The piston 2 is clamped by the nut 13 via the piston n5, and the piston 2 is fixed to the piston n5. A fitting recess 14,15 is formed in the outer circumference of the piston 2 in an annular shape. Rider rings 16 and 17, which are annular sealing members, are fitted into these fitting recesses 14 and 15. This makes the cylinder chamber 18 airtight.

The piston 2 shares a common horizontal axis with the piston rod 5, which axis coincides with the thin line of the cylinder 1 when the axis of the rider ring 16.1'7 is not worn.

As the rider rings 16 and 17 wear out during operation, the piston 2 and piston rod 5 are displaced downward by an amount corresponding to the amount of wear, and this causes the piston 2 to align with the axis of the piston rod 5. , the axis of the cylinder 1 will be misaligned.

FIG. 3 is an enlarged sectional view of the vicinity of the rider ring 16. The rider ring 1G is made of Teflon (trade name) or has a structure in which Teflon contains carbon. The same thing happens when you flash another Rider Ring 171. The cylinder 1 and piston 2 are made of a metallic material such as high chromium nickel. The distance d between the inner circumferential surface of the cylinder 1 and the outer circumferential surface of the piston 2 is rider ring IG+1
In the initial state where 7 is not worn out, it is about 5+o+a, and its minimum usable value is about 0.71.

FIG. 4 is an enlarged sectional view of the end of the piston 2 on the cylinder head side. I got 2 pistons. A thin disc-shaped limb detection member is fixed to the nut 13. As the front side of this liquid detection member is shown in FIG.
A right cylindrical protrusion N1 protruding downward from the line toward the cylinder head 20, and an annular groove formed on the outer periphery of the protrusion N1? The tube 11, the annular protrusion N2 formed by the external force, and the annular groove M2 formed on the outside thereof (1
Eh, and the annular protrusion N3 formed by that external force, and the same way? 7) M3, protrusion N4, and groove M4 are formed concentrically. The axis of the projection N1 coincides with the axis of the piston 2, indicated by the reference numeral 1)0.

The center of the radial width of the groove M1 is indicated by the reference p1,
Also, the center of the radial width of the protrusion) 12 is referenced 1]2
Similarly, the center of the groove M2 in the width direction is
It is indicated by reference numeral 1]3. The end surfaces of the protrusions N1 to N4 and the bottoms of the protrusions N1 to λ14 are flat.

An end portion 23 of an optical fiber 22 is fixed to the cylinder head 20 . This end 23 has an axis that coincides with the axis of the cylinder 1. The optical fiber 22 has a large number of fiber strands (they are grouped into two groups, one group 22a is supplied with light from the light source 24, and the light of the natural group is Hikari 7 Aiba Cable Line 22
b is connected to the light receiving element 25.

FIG. 6 is a front view of the end portion 23 of the optical fiber 22. FIG.

Light from light source 2.1 is supplied to Z1 light 7 Aiha cable line 22
A is indicated by a white circle in FIG. 6, and the light is irradiated from the end 23 toward the member 19 to be detected. The light 7 fiber cumulative line 2211 to which the reflected light is guided is fpJ6
It is indicated by a black circle in the figure. 1 in mGI21(1)
So, the fiber material λ22a.

22b are mixed, and in FIG. 6(2), the end portion 23
In FIG. 6(3), the fiber strand 22a is placed in the center, and the fibers 7hQ22+jht are placed around the outer periphery. At the end 23 of the optical fiber 22, a bare fiber 22a is formed in the manner shown in FIG.

221J may be arranged, and may be arranged in the form of a pond.

7th [ ] shows a waveform in which peak values of the output voltage are connected over time of the output of the light receiving element 25; and the axis of piston 2 coincide, and at this time,
The axis of the end 3iS 23 of the optical fiber 22 and the axis po of the protrusion N1 of the member to be detected 19 coincide. At this time, the light from the optical fiber element Q22a is irradiated from the end portion 23 to the end face of the protrusion N1, is reflected, and is guided to the light receiving element 25 via the fiber string 221). Since the distance between the end 23 of the optical 7 eyelid 22 and the end surface of the protrusion N1 is small, the amount of light received by the light receiving system element 25 is relatively large, and the output voltage thereof is large as indicated by reference mark 1.

As time passes, the lower portions of the rider rings 16, 17 slide against the inner circumferential surface of the cylinder 1 and wear, and the amount of wear increases. As a result, the optical fiber strand 22 from the end portion 23
The light passing through a is irradiated to the bottom of the vortex M1, and the light reflected at the bottom of the groove M1 is transmitted from the end 23 to the fiber element 1i22.
The light is applied to the light receiving element 25 via t+. Yu fiber 22
Since the distance between the end 23 of the groove M1 and the bottom of the groove M1 is large, the amount of light received by the light receiving system element 25 decreases as shown by the reference numeral 2 of the 7121st part. Further, due to wear of the rider ring IG, 17, the light from the end portion 23 is transmitted to the protrusion N+1.
Groove M2, protrusion N3. Groove M3. ...It is reflected in the order of C, and the output voltage corresponding to the amount of light received by the light receiving element 25 is 6.
-ζ increases and decreases as time passes.

The diameter of the central protrusion N1 of the member to be detected 19 is, for example, 1+
o+a, grooves M1 to M4 and annular protrusion N2 to
When the radial width of N4 is 111IIfi, and the axis of the optical fiber 22 coincides with the axis 1]5, it is detected that the rider ring 16.17 has been displaced downward by a total of 5 logical rings. be able to. It is thus possible to determine that the wear amount of the rider ring 1.6.17 is 51616.

According to such an embodiment, no electrical components are exposed within the cylinder chamber 18, thus providing an essentially explosion-proof structure. The advantage is that since the electrical arrangement is located outside the cylinder 1, maintenance and repair of such electrical arrangement can be carried out without stopping the movement of the piston 2. There is. Incidentally, since the evaporated gas of the liquefied natural bus is clean, the end face 23 of the optical fiber 22 and the member to be detected 19 are not contaminated.

Figure f'f'sF3 is a front view of a member to be detected 2G according to another embodiment of the present invention. In the above embodiment, the detected member 1
Although the jib surfaces of the two protrusions N1 to N4 and the bottoms of the grooves M1 to M4 are perpendicular to the axis of the piston 2, which provides good reflectivity, in the embodiment shown in FIG.
The detected member 26 has a flat plate shape, and the surface facing the end 23 of the optical fiber 22 is perpendicular to the axis of the piston 2 and forms one plane. Central head Nla and a ring f concentrically surrounding it H area M 1 a + N 2 a +
N 3 a + N (3a r N 4 a + N
(4a is formed, the regions N1a to N4a are flat plates and have high reflectance, and the remaining regions Mla to M4a are satin-like fine uneven surfaces and have low reflectance.

Such a member to be detected 26 can also be used in place of the single member to be detected in the above-described embodiment in the present invention.

FIG. 9 is a sectional view of another embodiment of the invention.

This embodiment is similar to the previous embodiment, in which a coil 27 is provided on the circumferential wall of the cylinder, where corresponding parts bear the same reference numerals. This coil 27 faces the entry point 2 when the piston 2 is at the top dead center 28, and is located away from the piston 2 when the piston 2 is at the bottom dead center. The fill 27 is excited by the oscillator 30, thereby generating a high frequency magnetic field from the coil 27 to the piston 2.

When the fill 27 faces the piston 2, eddy current loss occurs and the output of the oscillator 30 changes low.

The output of the oscillator 30 is passed through a line 31 to a detection circuit 32 to obtain an envelope. Oscillator 30 line 31
4 is a function of the distance IJ 1 between the filler 27 and the piston 2 and the first equation, where k is a constant.

di = −V (1) The peak value of this voltage decreases (↑) due to the increase in wear amount of the rider ring 16 and 17 with time changes, as shown in Fig. 10. The output circuit 33 responds to the output from the rugged wave enclosure 32, discriminates the level of the output, determines mQ, and issues a ':J signal when the distance d1 between the piston 2 and the cylinder 1 reaches the minimum allowable value. In this example, the interval d
It is possible to detect on the order of 1 μm, and it is also possible to pump fluids containing dirt and the like.

Figure f511 is a sectional view of a further embodiment of the present invention. This ':X' example is similar to the previous example 1. L,
Corresponding parts are given the same reference numerals. The main point of interest is that a transmitter 35 is provided in the cavity 34 of the piston 2. A detection element 36 is provided on the peripheral wall of the piston 2 so as to face the inner peripheral surface of the cylinder 1.

The detection element 3G may be a magnetic detection element such as a coil or a Hall element, or may be a combination of a light emitting element and a light receiving element. Between.

An electrical signal corresponding to the distance d2 is given to the transmitter 35.

The transmitter 35 receives the output from the detection element 36 corresponding to the interval d2 and wirelessly transmits a signal representing the interval d2. Receiver r placed near cylinder 1: i3'
g 37 has an antenna 38 and receives radio signals from the transmitter 35. The distance J2 between the receivers 37
is recorded by record 139.

FIG. 12 represents the peak value of the output voltage from the sensing element 3G detected by the receiver 37 and recorded and displayed at 7+39, and thus the interval d2. Over time, the rider rings 16, 17 wear out, which causes the distance d2 to decrease. Therefore, the output voltage of the detection system T-36 decreases.

A battery 40 for powering the transmitter 35 is contained within the piston 2.

In such an embodiment, the detection system T-36 can be easily installed on the piston 2, and the distance d2 can be measured, for example, on the order of a micrometer.

The present invention not only improves the compression allowance but also the reciprocating type (r
9. 177 in series, for example, IJ for internal combustion 1 air volume etc.
It can be carried out even if In the embodiments described above, the piston was provided with a rider ring IG, 17 (although such a sealing village may also be provided on the inner peripheral surface of the cylinder facing the piston).

Effects As described above, according to the present invention, it is possible to prevent wear of seals such as rider rings that keep the outer circumferential surface of the piston and the inner circumferential surface of the cylinder loosely connected. .

Therefore, even if the amount of wear on the seal village increases rapidly due to changes in the operating condition f'', the amount of wear is detected,
This can prevent damage caused by contact between the screw 1 and the cylinder.

[Brief explanation of drawings]

Fig. 1 is an overall sectional view of an embodiment of the present invention, Fig. 2 is an enlarged sectional view of the vicinity of screw 1 and 2, and Fig. r53 is a live ring 1.
6 is an enlarged sectional view of the vicinity of 6, FIG. 4 is an enlarged sectional view of the end of the piston 2 on the cylinder head side, FIG. 5 is a front view of the detected member 19, and FIG. 6 is an riL! 1523, FIG. 7 is a waveform diagram showing the time course of the output of the light receiving element T25, and FIG. 8 is the detected member 2G of the embodiment of the present invention.
FIG. 9 is a sectional view of an embodiment of the pond of the present invention, and FIG.
Figure 0 is a waveform diagram showing the envelope of the output from m'4'; FIG. 3 is a waveform diagram showing the output voltage corresponding to d2. 1...Cylinder, 2...Piston, IG, 17...
・Live ring, 19.26...Detected member, 22・
... Optical fiber, 24... Light source, 25... Light receiving element, 27... Fill, 30... Oscillator, 32... Detection circuit, 33... Output circuit, 35... Transmitter ,3G
...Detection element, 37...Receiver agent Patent attorney Number of strokes Keiichi Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fees Fig. 11 Fig. 12 Snore Questions

Claims (1)

[Claims] A piston reciprocating movement within a cylinder, and an annular sealing material provided on the piston in airtight contact with the inner circumferential surface of the cylinder. for a piston, characterized in that it includes a detection element that derives a detection signal corresponding to the misalignment of the axes between the cylinder and the piston, and a means for measuring the amount of wear of the seal material in response to the output from the detection element. Seal material wear measuring device.