JPS59117960A - Mechanical seal for water pump - Google Patents

Abstract

PURPOSE:To reduce the noise of a mechanical seal for water pump by forming the string-shaped grooves having a specific shape onto the slidable contact surface of the mechanical seal. CONSTITUTION:The inside part of each string-shaped groove 12 formed on the slidable surface of a trailing ring 4 for a mechanical seal 3 is opened and allowed to communicate to the inner peripheral side of the trailing ring 4, and the outside part extends rearwards in the direction of relative revolution of the trailing ring 4 with respect to a seat ring 5 and is closed in the intermediate part on the slidable surface. When the trailing ring 4 stops revolution, the slidable surfaces of the both rings 4 and 5 are attached in parallel state each other, and leak of water is prevented by the rand part 13 on the outer periphery. When the trailing ring 4 is revolved, it is thermally deformed, and the thickness of the inner part is increased, and the rand part 13 on the outer periphery is separated from the slidable surface of the seat ring 5. Therefore, inflow of water into the rand part 13 is relatively facilitated, and the lubrication condition at this part is improved, and the slidable surface is cooled, and generation of abnormal noise can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanical seal for a water pump. Generally, a mechanical seal for a water pump/F4 installed in an engine cooling system has a seat ring and a driven ring in sliding contact with each other. This prevents water on the outer circumferential side from leaking into the atmosphere on the inner circumferential side. In mechanical seals for water pumps, the moist bone fluid on the sliding surface becomes water, so the sliding surface is different from mechanical seals where bending becomes the lubricating fluid, such as mechanical seals for car cooler compressors. The sliding conditions of the surface were poor, and stellar kinks were likely to occur, resulting in noise. In the past, this interference was not considered a problem because it was relatively small compared to the noise 74 of other engines, etc., but as the noise of engines, etc. has been reduced, it has become especially Engines with low M noise (becoming a problem in the L rotation range).

In view of these considerations, the present invention provides a mechanical seal for a water pump that can reduce noise.

The following is a description of the present invention for the JC example shown below.
In Figure 81, (1) is the casing of the water pump, and (2) is the cylindrical fjl piece 1l of this casing f1).
a) is a rotating shaft that is rotatably supported by a bearing (not shown) inserted into the cylindrical IMiJIa), and the left end of this rotating shaft (2) is inserted through a pulley (not shown) and a bell I~. It is linked to the engine as a driving chant.

A mechanical seal (:
3), and this mechanical seal (3) rotates together with the driven ring (4) which can be displaced in the Φ411 direction of rotation Ili+l+ [2) and the rotating shaft (2), but is fixed in the axial direction. It is equipped with a seat ring (5). The driven ring (4) is fitted along the axial direction onto the outer circumference of the tip of the inner cylindrical shape 7+1i (6a) constituting a part of the support member (6) so as to be able to move forward. Yes, and an axial groove (4a) provided on the inner circumference of the driven ring (4)
By engaging the axial protrusion (6b) provided on the outer periphery of the inner cylindrical Fil (I 6 a ), relative rotation between the two is prevented. The support member (6) includes a wall portion 16c extending from the two ends of the inner cylindrical portion (6a) in the radial direction, and an outer cylinder folded back to the right from the outer periphery of the 1, j, 1 portion (6C). The outer cylindrical portion (6d) has a flange portion (6e) bent by an external force in the radial direction from the outer cylindrical portion (6d).
) into the cylindrical part (la) of the casing (1) through the sealing member (7), the m of that part is
While maintaining M property, the driven ring (4) is fixed in the direction of rotation.

One end of a sealing member (8) is adhered to the right end surface of the wall (6C) of the supporting member (6) with adhesive, and the other end of the sealing member (8) is curved in the middle. By adhering it to the left end of the driven ring (4) in this state, the 'JAM' property between the support part 8 (6) and the seat link (4) is maintained. By elastically mounting a spring (9) between both ends of this seal member (8), the driven ring (4) is brought into elastic contact with the seat link (5). This seat ring (5) has a recess [10a] formed in a rotor (10) fixed to the rotating shaft (2) for performing a pump action.
It is attached inside via a floating gasket (11), which allows it to rotate together with the rotating shaft (2). In addition, contrary to the illustrated embodiment, a driven ring (4) that is displaceable in the axial direction with respect to the rotating shaft (2) is provided on the rotating shaft (2) so that it can rotate integrally therewith, and a seat ring ( 5) may be attached and fixed to the casing (1).

In a water pump having the above 471 configurations,
When the rotary shaft (2) is driven by the engine (see Figure 74), the rotor (1o) integrated therewith rotates and supplies water to each cooling section within the engine. At this time, water is sealed by the seal parts (7) and (8), and also by the sliding surface of the driven link (4) and seat link (5) of the mechanical seal (3). Become.

As shown in FIG. 2, thread grooves (I2) are formed at equal intervals on the inner circumference of the sliding surface of the driven link (4). The inner part of each yarn groove (12) is connected to the driven link (
The opening communicates with the inner peripheral side of the link 4), and the outer part extends toward the rear blade in the direction of the relative rotational force of the slave +1flJ link (4) with respect to the seat ring (5), and closes at the middle part of the sliding surface. Therefore, a flat land portion (13) continuous in the circumferential direction without a groove is formed on the outer peripheral portion of the sliding surface, and this driven ring (4) always has its Ji”V JH The sliding contact surface of the seat link (5) is made to contact in a flat state.

On the other hand, when the driven ring (4) rotates, the inner circumferential side of the driven ring (4) protrudes in the axial direction from the outer circumferential side due to the frictional heat caused by the sliding contact between the driven ring (4) and the seat ring (5). Such thermal deformation can be obtained by constructing the driven ring (4) with a carbon fiber or the like. Further, the other seat ring (5) may be made of stainless steel, alumina sintered body, or the like, which has little thermal deformation.

In addition, in a water pump for an engine cooling system, the fact that water is heated by the engine also promotes the above-mentioned thermal deformation.

In such a configuration, when the driven ring (4) is at room temperature, that is, when the rotation is stopped, the contact surfaces of both rings (4) and (5) are in contact with each other in a parallel state, and the land portion (I
3) prevents water leakage.

When the driven ring (4) is rotated, as described above, the driven ring (4) is thermally deformed and has an inner height, and due to the C warp, the land portion [ta] on the outer periphery is removed from the sliding surface of the seat ring (5). They become separated. This allows the water to flow to the land area (13).
It becomes relatively easy for the water to flow into the area, improving the smoothness conditions in that area, and cooling the contact area, thereby suppressing the occurrence of L?.

Then, the dihedral yarn tM (12) captures the water that leaks over the land portion (13) with the widened interval, and pushes it back to the outer circumference of the driven ring (4) by the pumping action caused by its rotation. Therefore, even if the above distance is increased, the water leakage will be 11 tons.
As shown in the later experimental results, the leakage amount is not only reduced compared to the conventional method, but also the sliding contact between the seal 1 and the ring (5), which is the mating material, is reduced. It also works on surfaces. In other words, since the lubricant condition between the driven ring (4) and the seat ring (5) is poor, the upper 56
Even if the land portion (13) is separated from the sliding contact surface of the mating material due to thermal deformation, adhesion occurs in the inner thread groove 2) flXli due to the welding and raises the sticking. It is thought that the above-mentioned system groove (12) prevents the generation or growth of the condensed r'f-shaped f-black, and prevents the generation of the abnormal noise. In addition, the yarn groove (12) stores foreign matter and abrasion powder, and prevents roughness and increased sliding resistance due to foreign matter and abrasion powder intervening between the sliding surfaces, and also prevents adhesion from occurring due to surface roughness. This function also functions to prevent abnormal noise from occurring from this point of view.

Next, Fig. 3 shows the results of a noise test on mechanical seals. Fig. 3 (a) is for the example shown in Fig. 2, and Fig. 3 (Tb) is for the example of the thread groove for comparison. Fig. 1c) shows the experimental results without the mechanical seal itself.

In this experiment, the rotary shaft (2) was rotated by a motor at 25 orpm with or without a mechanical seal installed in the casing 11), and when the mechanical seal was installed, it was actually used as a water pump. In the state in which water was being discharged, the noise was measured using a noise sensor set at a distance of approximately 150 mm, and this was subjected to the same wave number analysis. At the same time, the overall He was measured and the results are shown as mesh bar graphs at the right end of each figure.

As can be understood from the experimental results in Figure 3 fa) to tc), the sound pressure involved in the mechanical seal is shown by the shaded area in Figure 3 (II-8), and this result as well as the result of the above Therefore, it is determined that no substantial noise is generated in the apparatus of the present invention.

2 411! L'I is the amount of water leakage measured under the above experimental conditions for the above two types of mechanical seals. This experiment was carried out for each mechanical seal with the spring (9) I
The results of 10 measurements each with different II II forces are omitted.

(Experimental article I! 1) 0 test; Substantive test machine 0 rotation speed: 2000 rpm Q time: 100 hours ○ Close elbow fluid: Water (80°C) ○ Close MLE crab 1.5 + (g/ct! 4th As shown in the experimental results in the figure, the present invention has a small fu'
Both ranges of f are small, and excellent sealing performance is obtained.

In the above embodiment, the sliding surfaces of both rings are parallel at room temperature, but if the pressure of the dense water is small, the driven ring (4) may have an inner height shape even at room temperature. This makes it possible to suppress noise even before thermal deformation occurs. In this case, for example, when the radial width of the sliding surface is 2 to 4 mm, bJ+ can be set to about 3 to 1.0 μm, and the sliding surface is on the seat ring 15) side. It is desirable that the driven ring (4) made of carbon material is deformed and pressed into contact with the seat ring (5) by the elastic force of the spring (9), so that the inner height; 1 is smaller than the internal height in the natural state by tJ・, and especially in the case of a small internal height, the sliding surface of the driven ring 14) will become the sliding surface of the seal milling (5) due to the above deformation. Becomes closely attached.

In the above embodiment, the thread groove (12) is connected to the driven ring 14).
Although it is provided in the seat ring (5), it may also be provided in the seat ring (5). When providing a thread groove in the seat ring (5), this seat [
・The materials of the link (5) and the driven ring (4) are reversed from those in the embodiment described in -1-U, and both links that serve as sliding surfaces +4)
The area of the end face of i5) may also be reversed.

Furthermore, the depth, width, number, etc. of the yarn M'12112 (1,! yarn M'12112) can be determined as appropriate depending on the conditions of use, etc., and the yarn groove ( 12) can be formed in a substantially radial force direction.

As described above, according to the present invention, it is possible to reduce hft M of a mechanical seal for a water pump.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
The front view of the seat ring shown in FIG. 3, +8) to Ic) are diagrams showing the results of measuring back pressure and noise, respectively, and FIG. 4 is a diagram showing the results of measuring the amount of leakage. (1)...Casing (2)...Rotating shaft (3)...
・Mechanical seal (4)・・Driver ring (5)・
・Seat ring (12)...Thread groove (13)...Land part Fig. 1@2 Fig. 322- 3 2 Fig. 3 (a) 1113 Fig. (b) m3 Fig. (c)

Claims (1)

[Claims] A water filter that prevents water on the outer circumference from leaking into the atmosphere on the inner circumference at the +111 contact surface between the seat ring and the driven link that slides on the seat ring. In a mechanical seal for a pump, a thread groove is formed at 1 m from the above-mentioned point, the inner part opens and communicates with the inner periphery, and the outer part extends and opens toward the rear side of the relative rotation of both links. 9. In each case, the outer side of the yarn finish 14 is made a flat land part. Mechanical seal for water pump with gamma characteristics.