DE10312766B4 - gearmotor - Google Patents

Abstract

Geared motor, comprising an electric motor (12) and a gear, wherein an A-end shield (9) of the electric motor (12) with a metallic motor-side housing part (3) of the transmission for transmitting torque and / or force connects, the transmission at least one-stage planetary gear is, and the rotor (14) of the electric motor (12) with the sun gear (13) of the transmission is connected by means of a Einsteckritzels, wherein the rotor (14) together with the sun gear (13) in the A-bearing plate (9) is mounted , characterized in that between the A-bearing plate (9) of the electric motor (12) and the housing part (3) of the transmission over the circumference at least a portion of the contact surfaces of the compound covering heat barrier (8) for reducing the heat flow from the electric motor ( 12) is provided to the transmission, the connection is made detachable, the thermal barrier (8) consists of glass fiber, which is arranged in a recess of the A-bearing plate (9), and the heat perre (8) is annular shaped and effective as a seal, wherein the electric motor (12) is a servo motor for achieving high positioning accuracy, positioning dynamics and associated high speed, wherein the releasable connection is made by means of screws or grub screws that the housing parts (3, 9) press each other, wherein the releasably executed connection comprises threads for holding the housing parts (3, 9).

Description

The invention relates to a geared motor according to the preamble of claim 1.

Geared motors comprising an electric motor and a transmission are well known. The connection between the electric motor and transmission can also be done by means of a coupling.

Because of various effects, such as friction, ohmic power loss and eddy currents, engines and gears reach high temperatures during operation. Especially with servo drives high speeds and high accelerations are provided. To keep the operating temperature within the permissible range, therefore, the electric motor and gearbox must be sufficiently large. Another possibility for temperature reduction would be cooling mechanisms with active cooling, such as fans or water cooling, or the design of the motor with superconducting components.

The invention is therefore an object of the invention to provide a more compact geared motor in a cost effective manner with the least possible effort.

According to the invention the object is achieved in the geared motor according to the features indicated in claim 1.

Essential features of the invention in the geared motor are that the geared motor, an electric motor and a transmission, wherein a metallic gearbox-side housing part, in particular A-end shield of the engine, the electric motor with a metallic motorseitigem housing part of the transmission for transmitting torque and / or force forms a connection, wherein at least a part of the contact surfaces covering thermal barrier is provided between the housing parts and the connection is made detachable. The large temperature difference that exists between the engine and the gearbox at high load leads to a warming of the gearbox. An advantage of the invention is that the heat flow between the electric motor and transmission can be reduced, in particular the heat flow from the electric motor to the transmission, without the stability of the connection is impaired, the compound is beyond even even solvable. Advantageously, the transmission is now very compact executable because now less or no significant thermal load from the engine comes, so essentially no originating from the engine heat must be dissipated through the gearbox to the environment. Insulating material for the provision of a thermal barrier is cost-effective and inexpensive to install in the presence of a corresponding recess in at least one of the housing parts of the electric motor or the transmission. Although the thermal barrier needs a certain volume of construction, but the reduction of the overall volume of the transmission is much more significant. Active cooling and / or superconducting designs are therefore unnecessary. It is surprising in the invention that even a thermal insulation covering only a partial area of the total contact area results in a substantial temperature reduction. In particular, it is surprising that a thermal barrier provided on the housing is so advantageous and a thermal barrier between the rotor of the electric motor and the driving gear toothed part, for example a sun gear, is not absolutely necessary in order to use more compact planetary gears. Such a thermal barrier would further improve the heat flow from the electric motor to the transmission.

Another important advantage of the invention is that the life of the lubricant in the transmission is increased. This saves maintenance costs. Another advantage is that by means of a suitable choice and dimensioning of the thermal barrier tolerances are compensated, in particular axial tolerances.

In the embodiment according to the invention, the electric motor is a servomotor to achieve a high positioning accuracy, positioning dynamics and associated high speed. The advantage here is that with modern servo drives by means of the invention more compact solutions with the same performance are possible.

In the embodiment according to the invention, the detachable connection is produced by means of screws or setscrews which press the housing parts together. The advantage here is that standard parts are used, which do not need to be further insulated or are made of a special material to manufacture.

In the embodiment according to the invention, the detachable connection comprises threads for holding the housing parts together. The advantage here is that no further components to form the releasable connection are necessary and the number of components and thus the storage costs can be reduced.

In the embodiment according to the invention, the transmission is an at least one-stage planetary gear. The advantage here is that the thermal barrier can be used for a planetary gear, which has a much higher power loss or heat output per unit volume than a spur gear or many other types of gear.

In an advantageous embodiment of the geared motor is designed such that an operation at a speed of more than 6000 revolutions per hour with more than 10,000 hours of continuous operation causes no failure. The advantage here is that the thermal barrier in such fast-running transmissions, which also have a high heat production, allows such a long service life in the most compact embodiment.

In an advantageous embodiment, the motor shaft is connected to the sun gear of the driving stage of the planetary gear directly or by means of one or more components. The advantage here is that despite the immediate or almost immediate torque transfer, the thermal barrier on the housing causes a significant reduction of the heat flow to the gearbox out.

In the embodiment according to the invention, the thermal barrier comprises glass fiber. The advantage here is that manufacturing tolerances or load-related or heat-related tolerances, especially axial tolerances are compensated, since the glass fiber mat is not only heat-insulating but also elastic.

The invention will now be explained in more detail with reference to figures:
In the 1 the geared motor according to the invention is shown. It is designed as a servo drive and includes a planetary gear and a synchronous motor. The drive is designed for highly dynamic operation, in particular it can be used as a drive for handling devices, such as robots or the like. In this case, the geared motor is designed such that operation at a speed of more than 6000 revolutions per hour with more than 10,000 hours of continuous operation causes no failure. In addition, high accelerations are foreseeable in a rapidly successive way.

The rotor 14 of the electric motor 12 is by means of a Einsteckritzels with the sun gear 13 connected to the planetary gear. The sun 13 is engaged with the planetary pins 6 stored planet gears 5 , by means of the planet carrier, the output shaft 1 drive. This output shaft 1 is via an output shaft bearing 4 in the case 3 stored. By means of the housing 3 provided radial shaft seal 2 that is on the output shaft 1 is running, the interior of the transmission is sealed against the environment.

The rotor 14 is by means of the A-bearing plate 9 of the electric motor 12 in a housing-forming part of the electric motor 12 namely the A-camp 10 of the electric motor, stored and by means of the radial shaft seal 15 of the electric motor 12 sealed. The A-camp 10 of the electric motor 12 is by means of the locking ring 11 secured in the axial direction. The shaft nut 7 serves to secure the output shaft bearing 4

Between A-end shield 9 of the electric motor 12 and housing 3 is insulating material over the circumference 8th intended. The likewise introduced O-ring 16 seals the connection. A-end shield 9 and housing 3 are held together by screws, so are releasably connected. Also the O-ring 16 has a certain thermal insulation, which would be completely insufficient. Only by means of the insulating material 8th is achieved sufficient thermal insulation, which significantly reduces the heat flow, the high power of the drive from the electric motor 12 towards the gearbox. For example, the permissible operating temperature of the electric motor is 100 ° C and the permissible maximum operating temperature of the transmission is 90 ° C.

Without the insulating material 8th would the heat flow from the electric motor 12 increased to the transmission and the transmission, in particular its teeth and / or shaft seals, would be at risk. The insulating material 8th is provided in a recess of the housing, so that not too much space must be used. Due to the much more compact design of the planetary gear but a significant reduction in overall volume is achieved.

In the present inventive embodiment, a significant portion of the heat flows through the rotor 14 into the sun wheel 13 , In addition, a heat flow through the said screws and over the remaining contact surfaces between the gear housing flows 3 and motor housing.

In further exemplary embodiments according to the invention, the passage possibilities for the mentioned heat flows are carried out with an increased thermal resistance, in particular using insulating material 8th ,

As insulating material 8th Glass fiber mats are advantageously usable because they have a high melting temperature of about 700 ° C, a lower thermal conductivity 0.04 W / mK. In comparison, aluminum has a thermal conductivity of 238 W / mK. In addition, the glass fiber mat is designed to be elastic and therefore allows the compensation of axial tolerances that have different causes, in particular are production-related or only load-dependent or temperature-dependent.

According to 2 the geometric shape of the thermal barrier is to be selected ring-shaped with corresponding round motor centering. 2 shows a spatial view of such an annular thermal barrier of insulating material 8th , The recesses in the housing of the electric motor 12 are for receiving this annular heat barrier 8th shaped accordingly. During assembly, the insulating material 8th deforms and compensates for certain different tolerances, in particular axial. In addition, the assembled leads deformed and pressed insulating material 8th beyond a certain sealing function.

The geometric shape of the thermal barrier is square to choose at appropriate square flanges other embodiments of the invention.

In further embodiments of the invention, the housing part 3 designed with internal toothing. In other embodiments of the invention is in the housing part 3 a ring gear with internal teeth inserted and connected.

In the 4 is a further embodiment of the invention, the thermal barrier of insulating material 8th and A-end shield 9 shown the engine. It is in the 4d a spatial view of the thermal barrier shown.

In the 4a is the A-end shield 9 of the engine with the thermal lock shown in an axial plan view. In the 4b the corresponding sectional view is shown. In the 4c is the in 4b marked area shown enlarged.

LIST OF REFERENCE NUMBERS

1

output shaft

2

Radial shaft seal

3

casing

4

Output shaft bearing

5

planet

6

planet shaft

7

shaft nut

8th

insulating material

9

A-end shield of the engine

10

A bearing of the engine

11

circlip

12

engine

13

sun

14

rotor

15

Radial shaft sealing ring of the engine

16

O-ring

Claims (1)

Geared motor comprising an electric motor ( 12 ) and a gear, wherein an A-end shield ( 9 ) of the electric motor ( 12 ) with a metallic motor-side housing part ( 3 ) of the transmission for transmitting torque and / or force forms a connection, the transmission is an at least one-stage planetary gear, and the rotor ( 14 ) of the electric motor ( 12 ) with the sun wheel ( 13 ) of the transmission is connected by means of a Einsteckritzels, wherein the rotor ( 14 ) including sun gear ( 13 ) in the A-end shield ( 9 ), characterized in that between the A-shield ( 9 ) of the electric motor ( 12 ) and the housing part ( 3 ) of the transmission over the circumference of at least a portion of the contact surfaces of the compound covering thermal barrier ( 8th ) for reducing the heat flow from the electric motor ( 12 ) is provided to the transmission, the connection is made detachable, the thermal barrier ( 8th ) consists of glass fiber, which in a recess of the A-shield ( 9 ), and the thermal barrier ( 8th ) is annular and is effective as a seal, wherein the electric motor ( 12 ) is a servomotor to achieve a high positioning accuracy, positioning dynamics and associated high speed, wherein the releasable connection is carried out by means of screws or set screws, the housing parts ( 3 . 9 ), wherein the detachable connection comprises threads for holding the housing parts together ( 3 . 9 ).

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