JPS5911757B2 - Haguruma Pump Matahamota - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to introducing a required pressure to the outer surface of the sealing member, that is, the side opposite to the side that contacts the gear, in order to balance the loading force of the sealing member against the side surface of the gear. This invention relates to gear pumps or motors (hereinafter referred to as gear pumps, etc.).

This type of gear pump and the like that have been known so far have two types of areas, a high pressure area and a low pressure area, defined on the outer surface of the seal member.

However, the pressure in the tooth groove gradually increases as it approaches the discharge side, and does not remain low until a certain rotational position and suddenly increase to high pressure when the rotational position is exceeded.

However, as mentioned above, since the outer surface of the seal member is divided into a high pressure area and a low pressure area, the balance between the pressure in the tooth groove is lost at the boundary between these two areas, and this causes intense noise. Inconveniences may occur, such as burn-in or burn-in at the relevant portions.

In order to eliminate this drawback, the methods shown in FIGS. 1 to 3, for example, can be considered, but even in this case, there are drawbacks as will be described later, and it cannot be said to be sufficient.

Here, the specific structure of the device shown in FIGS. 1 to 3 will be described. The first seal 2 is fitted around the recessed surface 1a formed on the outside of the case body 1.

And the bushing 3.4 fitted into the case body 1
has a winding seal member 15.6 slightly protruding from its outer surface, and projections 3a and 3b at positions slightly apart from the winding bush 5.6.

4a and 4b are formed.

The protrusions 3a and 4a correspond to positions where the pressure inside the tooth groove of the gear is maintained at a low level, and the protrusions 3b and 4b correspond to positions where the pressure within the tooth groove changes from low pressure to slightly high pressure. It is.

The second seal 7 fitted inside the first seal 2 holds surrounding parts 7b and 7b', and the surrounding parts 7b and 7b' are connected to the protrusion 3b.

4b, and the other portions surround required portions of the circumferences of the winding seal members 5, 6 and the protrusions 3a, 4a.

Therefore, the area between the 1st and 2nd seals is a high pressure area, the surrounding part 7b,
The part surrounded by 7b' is a medium pressure area, and the surrounding parts 7b, 7b
The area surrounded by the second seal 7 excluding ' is a low pressure area.

Note that in the figure, reference numeral 8 indicates a high-pressure oil introduction hole, and reference numeral 9 indicates a medium-pressure oil introduction hole, and 10 indicates a low-pressure oil introduction hole.

The configuration described above can easily be considered as a means to eliminate the conventional drawbacks described above, but in this case, since high pressure acts around the second seal 7, the second seal 7 is As shown, abnormal deformation occurs and may cause the seal to break.

Also, unlike the above configuration, it may be possible to seal the low pressure area and the medium pressure area with separate O-rings, but in this case, each area will be narrowed due to the thickness of the O-ring itself, and the balance of the loading force will be affected. It is something that cannot be taken away.

The object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide a gear pump etc. in which the seal does not break or the area is not narrowed due to the seal.

First, a first embodiment shown in FIGS. 4 to 7 will be described.

A gear 12.13 is housed inside the case body 11, and gear shafts 14 to 17 are mounted on both sides of the gear 12.13.
Seal members 18 to 21 are arranged to hold the case body 110, and both outer sides of the case body 110 are closed with covers 22 and 23.

Note that the seal members 18 and 19, and 20 and 21 each form a set, and the configuration of each set is substantially the same, so the seal members 18 and 21 will be described below. IH! I will be explained.

The sealing member 18.1 is located outside the case body 11.
A depressed surface 11a is formed around the hole into which the hole 9 is fitted,
A first seal 24 is fitted around the recessed surface 11a.

The outer surfaces of the seal members 18 and 19 are at the same level as the recessed surface 11a when the seal members 18 and 19 are fitted into the case body 11 as shown in FIG.
Protrusions 18a and 19a are provided at a portion of the gear 1213, that is, at a position corresponding to a portion where the inside of the tooth groove of the gear 1213 is maintained at a low pressure, and a wound bushing 25. The outside of 26 is connected to the protrusions 18a and 19a.
It is made to protrude to a position where it is at the same level as .

a second seal 2 fitted inside the first seal 24;
7 maintains a shape that integrally surrounds the protruding portions of the winding bushes 25 and 26 and the protrusions 18a and 19a, while having surrounding portions 27a and 27a' that are separate sections from them. Chips 28 and 29 are fitted into the portions 27a and 27a'.

However, the surrounding portion 27a of the second seal 27.

The area surrounded by the area other than 27a' is where low pressure oil is introduced from the low oil introduction hole 30, which constitutes the low pressure area LAa, and also includes the surrounding parts 27a, 27a.
Inside ', medium pressure oil is introduced from medium pressure oil introduction holes 31 and 32, which constitute the medium pressure area MAa.

Furthermore, high pressure oil is introduced from the high pressure oil introduction hole 33 between the first and second seals 24 and 27, which constitutes a high pressure area HAa.

That is, the inner end of each of the introduction holes 30 to 33 is connected to the gear 12.
．． 13, and the pressure oil in the tooth groove corresponding to these openings is guided to the corresponding area, and the pressure in each area is equal to the pressure in the tooth groove, and the loading cover of the seal member against the side surface of the gear. is to be balanced.

With the above configuration, when high pressure is applied to the second seal 27, the surrounding parts 27a and 27a' move while surrounding the chips 28 and 29, so the second seal 27 is abnormally deformed. It never runs out.

It should be noted that if the intermediate pressure areas in the above embodiment are provided in multiple stages, the loading force of the seal member against the side surface of the gear will be more balanced, but this point was focused on in the second actual case shown in FIG. 8.

Therefore, this second embodiment will be explained, and the same reference numerals as in the first embodiment will be used for the same items as in the first embodiment.

This second embodiment has four surrounding parts 34 in the second seal 34.
a, 34b, 34a', 34b' are provided, and chips 35 to 38 are fitted into each of them.
13 is in a relationship in which another enclosing portion is connected in the rotational direction.

Further, the first and second seals in the first and second actual cases are the case body 110 cover 22, as in the third actual example shown in FIG.
Of course, it may be provided on the 23 side.

However, in this case, the outer surfaces of the case body and the seal member must be on the same level, and portions corresponding to the recessed surfaces and protrusions in the first and second embodiments must be provided on the cover side.

Further, in each of the above embodiments, a bush type seal member is used, but the seal member does not necessarily have to be a bush type.

That is, the present invention is for sealing the sides of the gear and maintaining its loading balance.

Therefore, considering the means for maintaining this loading balance, in addition to the bushings, for example, conventionally used side plates are also included in the sealing member according to the present invention.

As is clear from the above description, according to the gear pump etc. of the present invention, since the intermediate pressure area is provided on the outer surface of the seal member separately from the high pressure area and the low pressure area, the loading force of the seal member against the gear side surface is improved. It's about balance.

In addition, the medium pressure area is divided by an enclosing part provided integrally with the second seal that partitions the low pressure area, and the chip is fitted into the enclosing part, so that when high pressure is applied to the second seal, the enclosing part The part may move slightly with the above step,
Therefore, the second seal will not be abnormally deformed or broken.

[Brief explanation of the drawing]

Figures 1 to 3 show examples that are usually considered to solve the conventional drawbacks, Figure 1 is a side view of the case body with the cover removed, Figure 2 is a perspective view of the sealing member,
Fig. 3 is a partial side view showing a modified example of the second seal in operation, Figs. 4 to 7 show the first embodiment of the present invention, Fig. 4 is a longitudinal sectional view, and Fig. ■-IV line sectional view, 6th
The figure is a perspective view of the seal member, Figure 7 is a front view of the second seal, Figure 8 is a sectional view showing the second embodiment and corresponds to Figure 5 above, and Figure 9 is the third embodiment. It is a partially omitted vertical cross-sectional view showing an example. 12.13 is a gear, 18 to 21 are seal members, 24 is a first seal, 27.34 is a second seal, 27a, 27a
', 34a, 34b, 34a'. 34b' is the surrounding part, 28, 29. 35 to 38 are the tips,
HAa is a high pressure area, MAa is a medium pressure area, and LAa is a low pressure area.

Claims (1)

[Claims] 1. A first seal is provided on the outside of the sealing member provided on the side of the gear, that is, on the side opposite to the side that contacts the gear, and a second seal is provided inside this first seal, and with these two seals, In the gear pump or motor that divides a high pressure area and a low pressure area and introduces into both areas the pressure in the tooth groove corresponding to the area to balance the loading force of the sealing member, the second
A gear pump or motor comprising a seal integrally formed with a surrounding portion, a portion surrounded by the surrounding portion serving as an intermediate pressure area, and a chip independent of the sealing member being fitted into the surrounding portion.