CS197631B1 - Box for the gearings with the tooth wheels - Google Patents

Abstract

Housing for a gearwheel drive comprises a part which transmits the bearing forces to the base plate, and a housing (10) which completely encompasses the part (1) but in a contact-free manner. The components of a sealing or spring (13) nature located between the base plate and the housing (9) are either principally of a nature to withstand bending or torsion (apart from their sealing and housing support functions). Alternatively they can be of the rubber elastic non-metal sealing type, subject to pressure, or functionally divided between pressure affected rubber parts and bending or torsion subjected metal spring components. The sealing of the housing to shafts can be by means of metal spring bellows, metal, non-metal ring or pot-shaped components.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gearbox housing which is a mechanical converter of speed, direction of rotation and torque, wherein the gearboxes have their own dual function housing, unless they are integral with the drive units or working machines, and this is to transfer the force of the rotating components from the bearings to the foundation and to place the rotating components in the oil bath. Gearboxes · · gearboxes. The embodiments according to the invention are expediently used wherever there is a need to reduce the noise level resulting from the engagement of the gear train or where the support parts of the convection-cooled gear housing are to be made of a material with a low thermal conductivity without reducing heat dissipation. .

It is known that the sound energy of geared gearboxes having their own enclosed housing is radiated to the environment from the engagement of the teeth by the interior of the gearbox in a direct way, whereas the walls of the housing are only insignificantly small. The main route, which emits more than 95% of the sound energy to the gearbox environment, is the path leading to the sound from the teeth engagement of the gear housings, shafts, bearings and bearing racks to the casing, which is accompanied by glitching movements. to which they are energized by the sound of said bodies which co-oscillate the ambient air, thereby making this ambient air the primary sound source.

It has been tried several times to utilize this knowledge to reduce the sound emission of gearboxes. For example, a transmission was tested in which the side walls on which the bearing bases were supported were strengthened, while the other two side walls as well as the top closure wall were made thin and therefore flexible. The thin side walls were fastened to the reinforced bearing forces engaging the side walls and the base plate directly behind the insertion of the rubber layer, which also sealed the housing.

The planetary gearbox was also tested, whose encapsulation part of the housing was supported on the base plate by special rubber profile seals, without the encapsulation part being directly connected to the bearing racks.

The difficulties encountered so far have not made it possible to make full use of the known physical relationships mentioned in the introduction to reduce the noise of the gearboxes.

For example, the first variant mentioned above can only achieve a partial reduction in the noise of geared gearboxes, since the large side walls bearing the bearing racks are still an intense source of noise, even when amplified, because they form the largest part of the transmission surface.

In the second variant tested, that is, in a planetary gear unit, the housing enclosure member is subjected to such strong pulses from the motherboard that the housing encloses an oscillation in the audible range, despite the seal. Special trouble. it consists in achieving a sufficiently low elasticity of the relatively large-area gasket and in achieving the pressing pressure necessary to ensure the sealing of the oil without exceeding the strength of the gasket material.

The purpose of the invention is to fully realize the principle of the sound-insulating separation of the forces absorbed by the individual and the encapsulating parts of the gearbox in the audible frequency range, whereby other economic effects, such as partial replacement of materials, can be achieved. heat and weight reduction of mass production gearboxes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a gearbox housing comprising a base plate on which two bearing racks, connected by an anchor rod, for gear shafts, and a housing surrounding the bearing racks are mounted such that The principle of 'sound-insulating separation of the forces absorbed by the individual and encapsulating parts of the gearbox housing' has been implemented to the best possible degree.

According to the invention, this object is achieved by providing spring plates between the housing and the base plate, elastic cuff-shaped plates between the housing and the bearing rack on the output side of the gear shafts, and pressure springs between the bearing rack covers and the housing capturing the total weight of the housing. The purpose of the spring plates and the compression springs is to prevent the introduction of • oscillations in the audible range, • coming from the bearing stand or the base plate, into the large housing. The housing of the housing on the output side of the gear shafts and between the housing and the base plate is provided by elastic and resilient cuff-shaped sheets which, by their flexibility, allow axial and radial changes of the housing position almost without application of force. The limitation of the mobility of the housing is accomplished by stops which are preferably located on the bearing stand. '

In particular, the sub-proportions of noise are more pronounced as a result of the reduction of sound emission compared to conventional constructions. Therefore, it is necessary to adjust the holes for the shafts so that at the free outlet there is a sound coming from the oil seals. rings absorbed by the most absorbent lining.

The physical separation of the supporting and encapsulating parts according to their function makes it possible to make them. bearing rack and housing made of different materials, while partially retaining the required properties. For example, in gearboxes without an oil cooler, a reduction in the consumption of metallic materials is achieved if the bearing rack is made of a non-metallic material such as glass ceramics, plastic and the like, which it usually has. -low coefficient of thermal conductivity, and · necessary heat dissipation · by convection and · radiation, adopts a housing made of metal for this purpose. _{; :}

Geared gearboxes that have been developed in the series and are manufactured with or without an oil cooler · are subject to a heavy load when operating with an oil cooler in terms of · gearing, shafts and bearings.

On the other hand, when operating without an oil cooler, their permissible load is determined by the limiting heat output, which depends on the dimensions of the enclosure at the first approximation under otherwise similar conditions. · In these cases, all the internal components of the gearbox, i.e. the gears, shafts, bearings and bearing racks, are oversized, which, with a large number of pieces, · annually produced gearboxes in the series, · which are · designed for radiator operation, they are supplied without a heat sink, meaning a considerable economy-wide loss of material and work during processing. =

The design of the gearbox housings makes it possible to design the gearboxes in such a way that, even with the lowest material and machining costs, gearboxes supplied without oil cooler are also stressed in terms of strength and heat balance is balanced because the bearing The stand dimensioned according to the actual power is built into the gearbox dimensioned according to the heat balance.

The most effective wall thickness of the housing, when made of sheet steel, is about 1.5 to 2 mm, respecting acoustic requirements. The wall thickness · 2 mm is favorable for the strength required.

Compared to conventional embodiments, the solution according to the invention has the following advantages: reduced sound emission by 10 dB (A) or more, the possibility of partial replacement of metallic housing materials with low-grade non-metallic materials. · Thermal conductivity coefficient · with unchanged good · heat dissipation by radiation and convection, substantial reduction of gearbox weight in gearboxes, sizes of which are optionally available with or without oil cooler, achieved by deviation from conventional gearbox design. ,.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in more detail by way of example in the accompanying drawings, in which: FIG. 1 is a front elevational view of the gearbox with the plane B-B in FIG. 2, FIG. 2 is a side view of the gearbox; Fig. 1, Fig. 3 detail C according to Fig. 2 and Fig. 4 sound damping at the shaft output from the housing.

The bearing racks, which consist of two horizontally divided caps 1 and bearing racks 2, 3, as well as reinforcing and connecting anchor rods 4, are provided in their holes 5, 6 with shafts on which the pinion 7 and the gear 8 are supported. These bearing racks are mounted on a base plate 9. A housing 10, made of sheet steel having a wall thickness of about 2 mm, surrounds the bearing racks and is supported on the base plate 9 by resilient plates 12, sealing the oil at the same time. .

If the required resilience of the spring plates 12 under load or deformation is too great, the weight of the sleeve 10 is absorbed by the compression springs 13 which are fastened to the caps 1 of the bearing racks.

The shaft passage is sealed by collar-shaped resilient plates 14 which are fastened on one end to the housing 10, while on the other end they are fastened to the ring 15 in which the shaft seal ring 16 is received. The ring 15 is fixed to the bearing stand by metal strips 17.

In order to attenuate the radiated sound emanating from the shaft sealing ring 16 and at the shaft outlets, a metal lining 18 is provided on the housing 10, which is covered with a sound absorbing material 19 on its inner side. '

The advantages of the solution according to the invention have been verified on the geared transmission in virtually a series of m (rpm) Mdi (Nm) number of rotational torque tests, which are given in. the following table. '

Experimental tests on gearboxes with a total gear ratio = = -3.15 resulted in the reduction of the noise level (AL) relative to the original state, as shown in the table:

P (kW) at L (dB / A /) ‘m max. power drop level

100, ,. . 1600 0 . 0 11. . . . 13 (15) 100 ALIGN! ,. . 1600 400. 66 7 ·. . . . 15 ’ 100 ALIGN! . . . 1600 900 148 11. . . 17 100 ALIGN! . . 1600 2000. J 329 6. .. . 19 Dec 100 ALIGN! . . . 1550 4400 708 7 ·. . . 16

The invention can be advantageously used in the industrial construction of gears.

Claims (2)

1. A gearbox housing consisting of a base plate on which two bearing racks for gear shafts are fastened together by an anchor rod; and from the housing surrounding and overlapping the bearing racks, indicated. in that the housing (10) is formed as a rectangular housing and made. of thin-walled sheet metal, for example 1 to 2 mm thick, is connected to the base plate (9) by spring plates (12), sealing the oil at the same time, the total weight of the sleeve ra (10) being absorbed by pressure springs · (13) mounted on the lids • a metal ring (15) provided with an oil seal ring (16) and connected to the housing is provided around the outlets (7, 8) of the gearbox shafts. (10) flexible plate (14) · cuff-shaped and with lid. · (1) bearing rack with flexible metal strips (17). Gearbox according to claim 1, characterized in that the noise-insulating housing (10) is preferably made of a non-metallic material, such as glass fibers.