DE10261479A1 - Elastic torque transmission and limiting coupling - Google Patents

Abstract

The invention relates to a device for transmitting a torque from a first shaft end (2) to a second shaft end (4). The shaft ends (2, 4) are positively coupled to one another and face one another with their end faces (3, 5). A torque spring (7) is accommodated in a cavity (14) of the first shaft end (2). With their inner sides (18, 19), the spring legs (8, 9) form a receiving opening (20, 36) for a pin (17; 28, 31, 32) which is formed on the second shaft end (4).

Description

technical area

Couplings have the function of shaft ends to connect with each other so that torques can be transmitted. at Couplings are between switchable and non-switchable couplings distinguished. Non-switchable couplings can either be used as rigid couplings, or as couplings to compensate for component misalignment or also be designed as elastic couplings.

State of technology

Couplings to which the requirement a high level of noise reduction adjustable elasticity as well as the requirement of a high axial and radial axis and angular misalignment are often very complex structure. Such couplings usually include insert parts Made of elastomer material surrounded by metallic components are. About the The coupling is made from inserts obtained from elastomer material a certain amount of Given elasticity. This through the selection and design of the elastomer materials posed elasticity can however, due to an excessive radial misalignment, which the two caused by the coupling can have shaft ends to be connected to one another. In the case of a too big one The two shaft ends to be coupled are offset the introduction of force from the driving shaft end to the driven one Shaft end so unfavorable that the original set elasticity an elastically designed clutch is negatively affected.

For couplings that are simply constructed are, the requirement for effective noise reduction can only be met to a limited extent by means of adjustable elasticity; in addition, simply constructed couplings have only a very limited number Offset compensation on and enable noise attenuation is limited. The compensability that can be achieved with simply constructed coupling types is limited to an axial offset of +/- 0.1 mm or an angular offset of about 1 °.

presentation the invention

With the solution proposed according to the invention, provide an elastic coupling, which on the one hand is considerable Degree of elasticity inherent and which, on the other hand, automatically interrupts the flow of force in the event of overload. The proposed according to the invention Coupling is simple and takes up very little space. The two shaft ends to be coupled together are by means of a torque spring coupled together in a cavity is embedded in one of the shaft ends. With the torque spring it is preferably a leg spring that either in cut slots or milled at one end of the shaft can be fitted. The slots receiving the leg spring, the one at the shaft end of the two shafts to be coupled together are located itself in the outer surface of the corresponding shaft end, the lateral surface being one Boring limited. The bore in one shaft end of the two Shafts to be coupled with one another provide the freedom for a suspension the torque spring in the event of an overload represents.

The one to be transmitted via the torque spring Torque can be varied by varying its material thickness or width and height of Leg of the leg spring set to the maximum transmissible torque become.

The space between the two spaced apart legs of the torque spring is dimensioned so that the lower shaft end, which with the Torque spring receiving shaft end to be coupled with a pin in the space between the two legs of the torque spring retracts. The tenon can be two along mutually extending surfaces have, the pin can also as a square or as a hexagon be trained. The legs of the torque spring, which are in the slots an outer surface of a the shaft ends are arranged essentially parallel facing each other with inner sides facing each other. The inside pages the leg of the torque spring form the contact surfaces for the pin the to be coupled with the shaft ends receiving the torque spring further shaft end. In addition to parallel guidance of the legs of the torque spring can - for example to accommodate a hexagonal Tenon - the Torque spring also include a contoured opening so that a preferably size contact surface between the pin-side contact surfaces and the inside of the Leg of the torque spring is accessible.

drawing

The invention is described below with reference to the drawing described in more detail.

It shows:

1 A perspective view of the coupling proposed according to the invention,

2 the torque spring and the geometry of the two shaft ends to be coupled together (exploded view)

3 a plan view of the coupled shaft ends,

4 a shaft end with a journal with two contact surfaces,

5 a shaft end to be coupled with egg nem designed as a square pin

6 a shaft end with a pin that is hexagonal and

7 a variant of a torque spring with a receiving opening, which is limited by shaped contact portions.

variants

1 is a perspective view of the coupling proposed according to the invention.

The coupling 1 includes a first shaft end 2 as well as a second shaft end 4 and in this case in the first shaft end 2 mounted torque spring 7 , The first shaft end 2 and the second shaft end 4 point to each other with their end faces 3 or 5 to. The contact surface of the face 3 of the first shaft end 2 and the front 5 of the second shaft end 4 forms a butt joint 6 along which the first shaft end 2 and the second shaft end 4 face each other. The torque spring 7 includes a first spring leg 8th as well as a second spring leg 9 , The feather legs 8th and 9 are together via a bracket 10 connected and extend according to the perspective representation in 1 in a vastness 11 through a cavity 14 in the first wave end 2 , The cavity 14 can e.g. B. as a bore in the first shaft end 2 be trained. The wide 11 , in the inside 18 respectively. 19 of the first feather leg 8th and the second spring leg 9 apart is constant over the length of the torque spring 7 between the bracket 10 and their feather leg ends 15 or 16.

The feather legs 8th respectively. 9 extend in one leg length 26 through the cavity, which is designed as a bore, for example 14 of the first shaft end 2 , This causes the spring legs to spring open 8th respectively. 9 in the radial direction with respect to the axis of symmetry of the first shaft end 2 possible.

The torque spring 7 is in slots 12 respectively. 13 added. The receiving slots are in pairs within a lateral surface section 3.1 of the first wave end 2 educated. The first slots 12 and the second receiving slots 13 are formed in pairs and lie within the jacket section 3.1 of the first shaft end 2 across from. The assembly of the torque spring 7 within the first and second receiving slots, respectively 12 . 13 is done by inserting the torque spring 7 into the designated slots 11 respectively. 13 , which are either cut or milled slots in the lateral surface section 3.1 can be trained. The torque spring 7 is inserted into the designated slots 12 respectively. 13 of the lateral surface section 3.1 introduced and is self-locking on the lateral surface section 3.1 of the shaft end 2 locked.

The thigh ends 15 respectively. 16 the outlets of the spring legs 8th respectively. 9 form are designed angled with respect to this and run approximately according to the curvature of the lateral surface section 3.1 of the first shaft end 2 , Between the spring leg ends 15 and 16 and the outside of the lateral surface section 3.1 there is a radial play 27 , About radial play 27 compensation can be compensated by 90 ° when overtightening or when springing up a shaft end designed as a square pin. In addition, radial play enables 27 easier assembly.

Between the inside 18 respectively. 19 the feather leg 8th and 9 the torque spring 7 is located as shown in 1 a square-shaped cone here 17 , The cone 17 is located on an end face of a second shaft end 4 ,

The face of the second shaft end 4 lies the ring-shaped end face of the first shaft end 2 , ie on the lateral surface section 3.1 across from.

2 shows the torque spring and the geometry of the two shaft ends to be coupled together.

At the front 5 of the second shaft end 4 is in the representation according to 2 for example, a square-shaped pin 17 , The in the axial length of the pin 17 which is a first investment area 24 as well as a second contact surface running at right angles to this 25 is by reference numerals 22 characterized. The cone 17 has a bevel 43 which a retraction of the pin 17 in the of the feather legs 8th respectively. 9 the torque spring 7 limited cavity 20 facilitated. The axial length 22 of the cone 17 corresponds to the axial length 23 the torque spring 7 as well as a length 21 in which the receiving slots 12 respectively. 13 on the lateral surface section 3.1 of the first shaft end 2 are trained.

When introducing it 17 in the cavity 20 the torque spring 7 lie the opposite second contact surfaces 25 on the inside 18 respectively. 19 the feather leg 8th and 9 the torque spring 7 on. The width of the cavity 20 between the inside of the spring legs 8th and 9 the torque spring 7 is with reference numerals 11 characterized. From the representation according to 2 can be seen that at the first shaft end 2 the receiving slots 12 respectively. 13 are arranged in pairs and on the lateral surface section 3.1 are opposite.

Due to the chosen geometry of the receiving slots 12 respectively. 13 , the axial length 23 the torque spring 7 as well as the axial extent 22 of the cone 17 , an extremely small coupling can be provided, in which the end face 5 of the second shaft end 4 the face 3 of the first shaft end 2 opposite.

The spring legs spring open 8th respectively. 9 the torque spring 7 - For example, in the case of transmission of an impermissibly high torque - it is possible that the spring legs 8th respectively. 9 in a cavity 14 of the first shaft end 2 are let in. A deformation, ie deflection of the spring legs 8th respectively. 9 inside the cavity 14 is thus guaranteed. Due to the spring properties of the spring legs 8th respectively. 9 the torque spring 7 can, depending on the material used, the choice of wall thickness and the choice of axial length 23 , the torque spring 7 be given a certain elasticity. The form-fit torque spring 7 can by varying or combining the material thickness and the free length 26 the feather leg 8th respectively. 9 set to the maximum torque to be transmitted.

As shown in 2 is the vastness 11 in which the feather legs 8th respectively. 9 the torque spring 7 run apart, over the length of the torque spring 7 seen, constant. The opposing second contact surfaces 25 of the cone 17 at the second shaft end 4 are therefore on the inside 18 respectively. 19 the feather leg 8th respectively. 9 on. An axial relative movement of the pin 17 , ie the second shaft end 4 relative to the first wave end 2 absorbed torque spring 7 is due to the geometry of the cavity 20 between the first spring leg 8th and the second spring leg 9 easily possible, so that an axial offset between the first shaft end 2 and the second shaft end 4 can be compensated.

3 shows a plan view of the coupled shaft ends.

From the representation according to 3 shows that the face 3 of the first shaft end 2 the face of the second shaft end 4 opposite. The contact area is through the butt joint 6 educated. On the outside of the lateral surface section 3.1 of the first shaft end 2 are the spring leg ends 15 or 16 recognizable, the outside of the lateral surface section 3.1 of the first shaft end 2 a radial game 27 exhibit.

4 shows a shaft end with a pin with two contact surfaces.

The second shaft end 4 according to this embodiment variant comprises a pin 17 , on which on the short, opposite sides and on a first longitudinal surface 29 and a second longitudinal surface 30 analogous to the representation of a square-shaped pin 17 according to 2 the bevel 43 is trained. The bevel 43 enables easier insertion of the pin 17 in the cavity 20 the torque spring 7 by the feather legs 8th respectively. 9 is limited. According to this variant, the first longitudinal surface is located 29 or the second longitudinal surface 30 as a 2-edged system 28 trained spigot 17 on the inside 18 respectively. 19 the torque spring 7 over the entire length. This embodiment variant favors a torsionally stiff design of the coupling proposed according to the invention 1 between the shaft ends 2 respectively. 4 ,

5 shows a shaft end to be coupled with a pin designed as a square.

The cone 17 at the second shaft end 4 comprises opposing first contact surfaces 24 , and at right angles to these oriented contact surfaces 25 , At the front of the pin 17 run the contact surfaces 24 respectively. 25 in a bevel 43 from that rounded in the face of the tenon 17 transforms. The face 5 of the second shaft end 4 lies in 5 not shown, this opposite end face 3 of the first shaft end 2 across from.

6 shows an alternative embodiment of the shaft end with a pin that has a hexagonal nut-shaped contour.

The cone 17 of the second shaft end 4 is as a six-edged system 32 executed. The variant of the second shaft end 4 according to 6 offers the advantage that an overload limit can be set. The number of edges of the tenons 17 the shaft end is inversely proportional to the overload limit.

7 shows an embodiment of the torque spring 7 with a receiving opening through the spring legs of the torque spring 7 molded system sections is limited.

The in the 1 . 2 and 3 torque spring shown 7 can have a diamond-shaped receiving opening in one embodiment 36 include. In contrast to the representation of the torque spring 7 according to the design variants in the 1 . 2 and 3 embrace the spring legs 8th respectively. 9 that are symmetrical to an axis of symmetry 33 the torque spring 7 are formed, plant sections 39 . 40 . 41 and 42 , The wide 11 , in which the insides 18 respectively. 19 the feather leg 8th and 9 is different from the torque spring 7 according to the 1 . 2 and 3 not constant. The one on the inside 18 respectively. 19 the feather leg 8th and 9 the torque spring 7 trained system sections 39 . 40 . 41 and 42 limit in the respective spring leg 8th or 9 essentially triangular spaces. At the plant sections 39 . 40 respectively. 41 and 42 can either be the first investment areas 24 or the second contact surfaces 25 of a cone 17 in a square system 31 according to 5 or the third or fourth contact surfaces 34 and 35 one in a hexagonal system 32 trained spigot 17 of the second shaft end 4 issue. In terms of area, the contact surfaces correspond 24 . 25 of the cone 17 according to 5 as well as the areas of the third contact area 34 and the fourth contact area 35 the area size of the system sections 39 . 40 respectively. 41 . 42 , The first face 37 and the second face 38 the torque fe the 7 according to 7 lie around the axial length 23 the torque spring 7 apart. The axial length 23 the torque spring 7 essentially corresponds (compare 2 ) the axial length 22 of the cone 17 at the second shaft end 4 , it is in a square system 31 , it is in a hexagon system 32 educated. This is a maximum coverage of the contact areas 24 . 25 respectively. 34 . 35 with the plant sections 39 . 40 respectively. 41 . 42 the torque spring 7 as shown in 7 guaranteed.

Analogous to the representation of the torque spring 7 according to the 1 . 2 and 3 run the feather legs 8th respectively. 9 in the in 7 shown embodiment variant in thigh areas 15 and 16 out.

With the solution proposed according to the invention, a coupling comprising a few components can be created in a simple manner, which takes up a very small amount of space and through the choice of material or the material thickness of the spring legs 8th respectively. 9 has a noise-reducing effect. The choice of material and the material thickness of the spring legs 8th respectively. 9 the torque spring 7 - according to the in the 1 . 2 . 3 respectively. 7 - Design variants shown, allows the setting of a certain elasticity. The relative displaceability of the pin 17 inside the cavity 20 the torque spring 7 according to the design variants in the 1 . 2 and 3 allows a higher axial and radial axial or angular misalignment of the shaft ends to be compensated for 2 and 4 to each other.

The torque spring 7 as shown in the 1 . 2 and 3 and as shown in 7 each has a bracket 10 opposite open end. This allows the torque spring to be expanded 7 if there is an impermissibly high torque. This can counteract the transmission of an impermissibly high torque. With the coupling proposed according to the invention 1 angular misalignments of several degrees and axial misalignments of several millimeters can be compensated. Be the components 2 . 4 and 7 the coupling proposed according to the invention 1 all made of the same material, they are largely insensitive to thermal expansion and cold shrinkage due to the same expansion coefficient. The components of the clutch are preferred 1 made of steel according to the design variants shown above.

With the coupling proposed according to the invention 1 To give an application example, asynchronous motors can be equipped for electric vehicle power steering.

1

clutch

2

first shaft end

3

front first shaft end

4

second shaft end

5

front second shaft end

6

butt joint

7

torque spring

8th

first spring leg

9

second spring leg

10

hanger

11

width

12

first receiving slots

13

second receiving slots

14

reaming

15

first Spring leg end

16

second Spring leg end

17

spigot

18

first inside

19

second inside

20

cavity spring element

21

Receiving slot length

22

Axial length of the pin 17

23

Axial length of Torque spring 7

24

first contact surface

25

second contact surface

26

free Length of spring leg 8, 9

27

radial clearance

28

2-Kant plant

29

first longitudinal surface

30

second longitudinal surface

31

4-Kant plant

32

6-Kant-conditioning

33

axis of symmetry torque spring

34

third contact surface

35

fourth contact surface

36

receiving opening

37

first face

38

second face

39

first contact section

40

second contact section

41

third contact section

42

fourth contact section

43

bevel

Claims (10)

Device for transmitting a torque from a first shaft end ( 2 ) to a second shaft end ( 4 ), the shaft ends ( 2 . 4 ) are positively coupled with each other and with their end faces ( 3 . 5 ) are arranged facing each other, characterized in that in a cavity ( 14 ) of the first shaft end ( 2 ) a torque spring ( 7 ) is recorded, the spring legs ( 8th . 9 ) with their insides ( 18 . 19 ) a receiving opening ( 20 . 36 ) for a spigot ( 17 ; 28 . 31 . 32 ) at the second shaft end ( 4 ) form. Device according to claim 1, characterized in that the cavity ( 14 ) of the first shaft end ( 2 ) from a lateral surface section ( 3.1 ) is limited in which recesses ( 12 . 13 ) to accommodate the torque spring ( 7 ) are trained. Device according to claim 2, characterized in that the recesses ( 12 . 13 ) on the lateral surface section ( 3.1 ) are arranged in pairs opposite to each other. Device according to claim 1, characterized in that spring leg ends ( 15 . 16 ) the torque spring ( 7 ) in relation to the spring legs ( 8th . 9 ) are angled and the first shaft end ( 2 ) with radial play ( 27 ) reach around. Device according to claim 1, characterized in that the spring legs ( 8th . 9 ) the torque spring ( 7 ) one recording width running parallel to each other ( 11 ) bounding insides ( 18 . 19 ) exhibit. Device according to claim 1, characterized in that the spring legs ( 8th . 9 ) the torque spring ( 7 ) System sections ( 39 . 40 ; 41 . 42 ) which have a receiving opening ( 36 ) inside the torque spring ( 7 ) limit. Device according to claim 6, characterized in that the receiving sections ( 39 . 40 ; 41 . 42 ) the spring leg ( 8th . 9 ) in terms of surface area ( 24 . 25 ; 34 . 35 ) of the cone ( 17 ) of the second shaft end ( 4 ) correspond. Device according to claim 2, characterized in that the length ( 21 ) the recesses ( 12 . 13 ) in the lateral surface section ( 3.1 ) the width ( 23 ) the torque spring ( 7 ) corresponds. Device according to claim 1, characterized in that the in the second shaft end ( 4 ) recorded spring leg ( 8th . 9 ) the torque spring ( 7 ) inside the cavity ( 14 ) in a free length that enables deflection ( 26 ) run. Device according to claim 1, characterized in that the first shaft end ( 2 ), the second shaft end ( 4 ) and the torque spring ( 7 ) are made of the same material.