DK145389B - DISTRIBUTOR VALVE FOR A HYDRAULIC GEAR MACHINE - Google Patents

Description

145389

BACKGROUND OF THE INVENTION The invention relates to a distributor valve for a hydraulic gear machine having an internally toothed gear and an internal toothed ring, in which one cylindrical rotary slider having the main shaft has two annular grooves connected to the inlet and 5 and extending from each of the annular grooves, transversely extending therewith. successive inlet and outlet distributor notes, which cooperate with housing fixtures, each leading to a control chamber leading to a displacement chamber.

Known distributor valves of this kind have a cylindrical surface which is provided with axial grooves which communicate with circular grooves in the distributor valve and wherein the axial grooves cooperate with control openings connected to a channel disposed in the gear unit housing, which is in communication with displacement chambers, which are located between the gear wheel and the gear ring (DE-AS 15 53 004).

In such a cogwheel with the said distributor valve, the efficiency decreases when driven in the upper speed range. This is especially true if the hydraulic gear unit must have very small external dimensions, for example 20 a housing with a length of only 10 cm and a diameter of only 6 cm.

It is also known to have disc-shaped flat sliders, in which radially extending distributor notes are alternately connected to an inner and an outer ring groove. Here are the same 25 disadvantages.

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Further, it is known from DE-OS 26 08 887 that the distributor notes on the outside of a cylindrical surface of the distributor valve do not extend exactly parallel to the axis, but at a small angle of 3 - 8 ° relative to the axis direction.

5 In this way, each distributor note may eventually come into contact with a similarly axially extending guide opening, so that pressure shocks are avoided.

SUMMARY OF THE INVENTION It is an object of the invention to provide a distributor valve of the kind described in the introduction by which the efficiency of hydraulic gear units, especially in the upper rpm range and at very small dimensions, can be improved.

The task is solved according to the invention in that each inlet distributor note at the end facing the annular groove has a bevel 15 extending in the direction of rotation.

In this way, the hydraulic fluid is more easily guided into the inlet flow notes so as to obtain improved flow. This reduces the losses and increases the degree of filling of the note. This precaution is particularly evident at higher rpm, because the gears here considered must be considered slow runners, but nevertheless have a very high pressure fluid capacity. The effect is also evident in machines with very small dimensions, because the notes here, due to the spatial conditions, have a correspondingly small flow cross-section with a correspondingly large flow resistance.

It is advantageous when each drain distributor note at the end facing the annular groove has an oblique section facing the pivot. This also provides similar advantages in the outlet area 30 as in the inlet area. In addition, such a machine can be operated as a motor or pump with the same result in both directions of rotation, whereby only the inlet and outlet sections change function.

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Further, the obliquely extending sections may be curved. This results in improved flow in the ducts.

The invention is described in more detail below by an exemplary embodiment shown in the drawing, which shows in FIG. 1 is a longitudinal section through a hydraulic gearwheel whose distributor valve is designed according to the invention; and FIG. 2 shows an unfolding of the circumferential surface of the distributor valve.

In the embodiment shown in FIG. 1, in particular a 10 engine, the housing consists of a cylindrical body 1, an intermediate disc 2, a tooth ring 3, an additional intermediate disc 4 as well as an inner tire disc 5 and an outer tire disc 6. These parts are by means of axial screws not shown. connected to each other. A drive shaft 7 is formed integrally with a pivot shaft 8 and over a cardan shaft 9 connected to a tooth ring 10. A fixed bearing disc 11 inserted at the bottom of the body, which at the same time retains a seal 12, forms together with one fixed to the pivot slider 8 bearing disc 13 an axial bearing.

The cylindrical body is provided internally with a sleeve 20 14 which has an inlet opening 15, outside the outline plane a outlet opening 16 and in between guide openings 17. The inlet opening 15 is connected over a housing channel 18 to a connection nozzle 19, the outlet opening 16 is above an outboard plane a drainage channel connected to a connecting plug 20.

The guide openings 17 are each connected over a housing channel 21 to the displacement chambers 22 which are formed between the teeth of the tooth ring 10 and the tooth ring 3. The house ducts 21 each between two teeth on the tooth ring? their number therefore corresponds to the number of cogwheels.

30 On the outside of the pivoting slide 8 there is also a shelf 23 in which are arranged alternately successive distributor notes 24 and 25, of which the inlet distributor nodes are connected to a ring groove 26 which is connected with the inlet opening 15, and of which the drain distributor notes 25 are connected to a drain ring groove 27 which is connected to the outlet opening 16.

A further stud 28 is closed with a screw 29. It can serve to relieve the inner space 30 of the swivel slide 8 through connection to a tank.

FIG. 2 shows that the inlet distributor notes 24 are connected by means of an arcuate inclined inlet section 31 to a location on the ring note 26 which is offset in the rotational direction relative to the distributor note D. Similarly, the outlet distributor notes 25 are provided with an arcuate inclined section. 32, which opens 15 in the ring groove 27 at a location which is offset in the direction of rotation of the distributor notes D. As a result, there are on the inlet side spikes 33 which exert an operating effect on the supplied pressure liquid, through which the flow conditions at the overflow is improved and flow losses 20 are reduced. Similar improvements appear on the drain side.

In this way, extremely small hydraulic motors can be produced, in which the swivel slider has a length of less than 6 cm and a diameter of only 3.5 cm and which, despite the inevitable small groove cross sections, has a very good efficiency.

Using the casing 23, the curved inlet and outlet sections 31 and 32 can be readily prepared, for example by means of an end mill. The machine can be operated not only as a motor, but also as a pump.