RU2450163C1 - Gear pump - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed pump comprises housing 1 accommodating engaged involute gears 2 and synchroniser gears with sufficient contact ratio. Top and initial circles of the latter coincide with those of gears 2. Mesh of gears 2 with one or more teeth with configuration formed by integrating several teeth of synchroniser teeth is ensured by appropriate fit of driven gear and synchroniser gear with shaft.

EFFECT: higher efficiency of gear pump.

2 cl, 3 dwg

Description

The invention relates to mechanical engineering and can be used as a hydraulic pump or hydraulic motor.

Known roller-blade machines (patents No. 2230194, F01C 1/14, publ. 06/10/2004. Roller-vane machine - [1], No. 2253735, F01C 1/14, publ. 10.06.2005. Roller-blade machine - [ 2]), which are used both as pumps and as hydraulic motors. In these devices, the pressure is created by the blade of the rotating rotor, and the separation of the high and low pressure chambers is carried out by rotating rollers. During the rotation of the rotor, the blade passes from one chamber to another, falling into the groove of the roller, which is ensured by the rotation of the rotor and rollers with the corresponding synchronizing gears.

These pumps are efficient and highly efficient. Their disadvantage is the need to use a reduction gearbox when used with a turbine having n = 10,000 rpm or more, because the revolutions of the rollers far exceed the revolutions of the impeller rotor, which limits the permissible maximum revolutions of these pumps.

Known gear pump external gearing, adopted for the prototype of the claimed invention, which is the easiest to manufacture and operate (Calculations and designs of aircraft hydraulic devices, T. M. Bashta, Oborongiz, 1961, p.133 - [3]). The creation of a fluid pressure in it is carried out by displacing the fluid with the tooth head of one gear from the tooth cavity of the gear coupled to it, and the separation of the injection cavities from the suction is provided by the sliding contact of a pair of lateral involute tooth surfaces that are engaged. This pump can be driven by a turbine in its characteristics (in terms of speed).

The disadvantages of the pump include the occurrence of various types of fluid leaks, compression of the fluid in the gear hollows, which occurs when each pair of teeth engages, as well as the harmful effect on the absorption of centrifugal fluid forces arising in the tooth cavities ([3] - p. 136 ... 148). These disadvantages reduce the efficiency of the gear pump.

The technical result to which the claimed invention is directed is to increase the efficiency of the gear pump by reducing the losses associated with the engagement of each pair of teeth on the gears creating a fluid head.

The technical result is achieved by the fact that in the gear pump, including the housing, the drive shaft, at least two involute gears meshing, creating a fluid pressure by displacing fluid with the head of one tooth of the wheel from the cavity of the tooth of the mating wheel, the new thing is that on the shafts gears installed synchronizing gears with a sufficient coefficient of overlap, the initial and pitch circles of which coincide with the corresponding circles of the gears, and gearing gears ec having one or more tooth configuration which is formed by combining several tooth in one tooth synchronizing gears, provided the appropriate compound of the driven wheels and the synchronizing gear to the shaft.

In a gear pump, the circumference of the valleys of the gears is the main circumference of the involute wheels.

The invention is illustrated in figure 1 - figure 3, where:

Figure 1 is a longitudinal section of an exemplary gear pump;

Figure 2 - layout of the pump with single-tooth wheels;

Figure 3 - layout of the pump with double teeth.

Here:

1 - pump housing;

2 - single-tooth wheel;

3 - double-tooth wheel;

4 - the contour of the teeth of the synchronizing gears;

5 - a drive shaft of a synchronizing gear;

6 - synchronizing gears;

7 - drive shaft of the pump;

Z _ZK - the number of teeth of the wheel;

Z _W - the number of teeth of the synchronizing gear;

Z _SHZ - the number of gear teeth combined into one tooth of the wheel;

m _zk - gear module;

m _W - gear module.

Case 1 has two cavities. In one, gears 2 or 3 of the pump are located, in the other, synchronizing gears 6, which are connected by gears 5 and 7 to the gears of the pump. The number of teeth in the wheels Z _ZK can be 1, 2, 3, etc. The condition for the gearing of the gears is the coincidence of the pitch and initial circumferences of the gears and synchronizing gears, as well as the fastening of the gears to the drive shafts to ensure contact of the side surfaces of the gear teeth.

The configuration of the contours of the teeth of the wheels can be obtained from the configuration of the synchronizing gears by combining the teeth of the synchronizing gears. So, single-tooth wheels can be obtained from the contours of the synchronizing gear with the number of teeth Z _W = 11 by combining in one tooth Z _W = 6 teeth of the synchronizing gears, as shown in _figure 2. A double-tooth wheel is obtained from a gear with the number of teeth Z _W = 10, 14, etc. At the same time, a new tooth combines Z _zz = 3, 4 gear teeth, respectively. Figure 3 shows the double-toothed wheels obtained from gears with Z _W = 10 teeth.

Gears with the number of teeth Z _W = 9.15, etc., are converted into a three-toothed wheel.

The ratio between Z _W ; Z _ZK and Z _SHZ when building the shape of the gear with a given Z _ZK is determined by the formula:

Z _w = Z _sk (2Z _ss -1).

To ensure reliable engagement of the gears, it is necessary that the number of teeth Z _w provides a sufficient overlap coefficient, because gearing of gears is ensured by gearing of synchronizing gears. In this case, it is not necessary to have the same module at the wheel and at the synchronizing gear, but it is enough to maintain equality:

m _{zk *} Z _zk = m _{w *} Z _w

When the drive shaft 7 rotates, the gear wheel and the driving synchronizing gear 6 located on this shaft begin to rotate, which, being engaged with the driven synchronizing gear by the shaft 5, drive the driven gear wheel, and since the driven gear wheel is mounted on the drive shaft 5 initially engaged with the mating gear, the engagement will be maintained during rotation.

A single-tooth wheel in one revolution by both lateral surfaces of the tooth will mesh once with the tooth of the mating pump wheel, and separately with each surface. Two-tooth - two times, three-tooth - three times, etc. Hence, the losses associated with the entry of the tooth head into the tooth cavity are sharply reduced.

In addition, reduced fluid leakage through the gap between the surfaces of the circumference of the protrusions and the circumference of the depressions, because the circumference of the depressions is the main circumference of the involutes of the side surfaces of the teeth of the wheel, and between the surfaces of the circles, the gap is the same as between the surfaces of the protrusions and the inner cylindrical surface of the housing.

Increasing the efficiency of the pump will increase the possibility of using a hydraulic actuator, bringing its efficiency to the values of the efficiency of gear reducers and gearboxes.

Claims (2)

1. A gear pump, comprising a housing, a drive shaft, at least two involute gears meshing, creating a fluid pressure by displacing fluid with the head of one tooth from the cavity of the mating wheel, characterized in that synchronizing gears are installed on the gear shafts with a sufficient overlap coefficient , in which the initial and pitch circles coincide with the corresponding circles of the gears, and the engagement of gears having one or more teeth, the configuration of which formed by combining several teeth of the synchronizing gears into one tooth, is provided by the corresponding connection of the driven wheels and the synchronizing gear with the shaft. 2. The gear pump according to claim 1, characterized in that the circumference of the cavities of the gears is the main circumference of the involute wheels.

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