DE10261479B4 - Elastic torque transmission and limiting clutch - Google Patents

Abstract

Facility for transmission a torque from a first shaft end (2) to a second Shaft end (4), wherein the shaft ends (2, 4) form-fitting with each other are coupled and facing each other with their end faces (3, 5) are arranged and in a cavity (14) of the first shaft end (2) a torque spring (7) is received, whose spring legs (8, 9) with their inner sides (18, 19) a receiving opening (20, 36) for forming a pin (17; 28, 31, 32) on the second shaft end (4), wherein spring leg ends (15, 16) of the torque spring (7) in relation are angled to the spring legs (8, 9) and the first shaft end (2) engage with radial clearance (27), characterized in that the Cavity (14) of the first shaft end (2) from a lateral surface portion (3.1) is limited, in which recesses (12, 13) for receiving the torque spring (7) are formed.

Description

technical area

clutches have the function of connecting shaft ends with each other Transmit torques can be. For clutches is between switchable and non-switchable couplings distinguished. Non-shiftable clutches can either be rigid couplings, or as a component offset compensating couplings or be designed as elastic couplings.

couplings, to which the requirement of high noise attenuation by adjustable elasticity and the requirement of compensating a high axial and radial Axis and Winkelversatzes are often very complex structure. Thus, such couplings usually include inserts made of elastomeric material enclosed by metallic components are. about the made of elastomeric material inserts is the coupling given a certain degree of elasticity. These through the selection and the design of the elastomeric materials set elasticity However, due to excessive radial displacement, the two may be affected by the clutch to be joined together shaft ends. In case of too big Offset of the two shaft ends to be coupled together takes place 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 coupling is adversely affected.

at Clutches that are simple in construction can meet the requirement of effective noise reduction by adjustable elasticity only limited Fulfills become; In addition, simply constructed couplings only have a very limited offset compensation and allow limited noise reduction. The achievable with simple design clutch types compensability is limited to an axial offset of +/- 0.1 mm or to an angular misalignment of about 1 °.

DE 333 726 C refers to a clutch. The coupling serves to connect a first and a second shaft end, wherein a multi-edged stump of the first shaft end is entrained by a number of resilient walls, for example leaf springs and a hollow of the second shaft end. The spring pressure is adjustable by approaching or removing guides, whereby the claimed part of the springs becomes smaller or larger, resulting in a stronger or weaker spring tension.

US 2,875,598 refers to a mechanical coupling. A flange-shaped shaft end is coupled to a shaft, wherein the two are positively coupled with each other. In a cavity of the flange-shaped shaft end a torque spring is added. Their spring legs form with their inner sides a receiving opening for the other end of the shaft.

US 4,518,369 refers to a coupling arrangement for rotating shafts. It is disclosed a spring whose open legs overlap one end of a shaft. The shaft over the cross spring is in turn mounted in a recess of another shaft under contact with the walls of the recess in the shaft end. By the boundary wall of the receiving opening for the spring this is biased.

US 6,202,879 B1 discloses a square which is clamped between open legs of a torque spring. If an unacceptably high torque is applied to the square, this is rotated within a recess which is bounded by complementarily shaped spring legs of the torque spring, this widens and slips through. The open legs of the torque spring are mounted in receiving slots which form an abutment, which in turn defines the Durchrutschmoment.

presentation the invention

Of the proposed according to the invention solution the task is based, a device for transmission To provide a torque on the one hand, a compensatory a high axial and radial axis or angular offset and on the other hand an elevated, however, has defined slip torque.

Following the solution proposed according to the invention, an elastic coupling can be provided which, on the one hand, inherits a considerable degree of elasticity and, on the other hand, automatically interrupts the power flow in case of overloads. The proposed coupling according to the invention is simple and requires a very small space. The two shaft ends to be coupled to each other are coupled together by means of a torque spring, which is embedded in a cavity at one of the shaft ends. The torsion spring is preferably a leg spring, which can be fitted either in cut-out slots or slots machined on a shaft end is. The leg spring receiving slots, which are formed at the shaft end of one of the two shafts to be coupled together, are located in the lateral surface of the corresponding shaft end, wherein the lateral surface defines a bore. The bore in a shaft end of the two waves to be coupled together provides the space for spring-loaded spring in the overload case.

That over the Torque spring to be transmitted Torque can by varying their material thickness or the width and the height of Leg of the leg spring adjusted to the maximum transmissible torque become.

Of the Freiraum formed between the two spaced apart Leg of the torque spring is dimensioned so that the lower shaft end, which to couple with the torque spring receiving shaft end is, with a pin in the space between the two legs the torque spring retracts. The pin can be two longitudinal mutually extending surfaces have, the pin can also as a four- or as a hexagon be educated. The legs of the torque spring in the slots a lateral surface of a the shaft ends are arranged substantially parallel each other with each other facing inner sides. The insides the legs of the torque spring form the contact surfaces for the pin of the with the torque spring receiving shaft ends to be coupled further shaft end. In addition to a parallel guide the legs of the torque spring can - for example for receiving a hexagonal Pin - the Torque spring also include a contoured opening, so that a preferably size contact surface between the pin-side abutment surfaces and the insides of the Leg of the torque spring is accessible.

drawing

Based In the drawings, the invention will be described below 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 with each other, (exploded view)

3 a top view of the mutually coupled shaft ends,

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

5 a shaft end to be coupled with a pin formed as a square

6 a shaft end with a pin that is hexagon shaped and

7 a variant of a torque spring with a receiving opening which is bounded by shaped abutment sections.

variants

1 is a perspective view of the present invention proposed coupling can be seen.

The coupling 1 includes a first shaft end 2 and a second shaft end 4 and in this case in the first shaft end 2 mounted torque spring 7 , The first wave end 2 and the second shaft end 4 point each other with their faces 3 respectively. 5 to. The contact surface of the front side 3 of the first shaft end 2 and the front side 5 of the second shaft end 4 forms a butt joint 6 along the first shaft end 2 and the second shaft end 4 opposite each other. The torque spring 7 includes a first spring leg 8th and a second spring leg 9 , The spring legs 8th and 9 are with each other via a hanger 10 connected and extend according to the perspective view in 1 in a distance 11 through a cavity 14 in the first wave end 2 , The cavity 14 can z. B. as a bore in the first shaft end 2 be educated. The wide 11 , in the insides 18 respectively. 19 of the first spring leg 8th and the second spring leg 9 Dismounting is constant over the length of the torque spring 7 between the hanger 10 and her spring leg ends 15 respectively. 16 ,

The spring legs 8th respectively. 9 extend in a leg length 26 through the cavity formed, for example, as a bore 14 of the first shaft end 2 , As a result, a springing of the spring legs 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 recording slots 12 respectively. 13 added. The receiving slots are in pairs within a lateral surface portion 3.1 of the first shaft end 2 educated. The first receiving slots 12 and the second receiving slots 13 are formed in pairs and are within the shell 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 12 . 13 done by inserting the torque spring 7 in the provided receiving slots 11 respectively. 13 , either as cut or milled slots in the lateral surface section 3.1 can be trained. The torque spring 7 gets into the provided receiving slots 12 respectively. 13 of the lateral surface section 3.1 introduced and is self-clamping on the lateral surface section 3.1 of the shaft end 2 locked.

The leg ends 15 respectively. 16 the outlets of the spring legs 8th respectively. 9 form are angled with respect to this and run approximately corresponding to the curvature of the lateral surface portion 3.1 of the first shaft end 2 , Between the spring leg ends 15 and 16 and the outside of the lateral surface portion 3.1 There is a radial play 27 , About the radial play 27 compensation can be compensated for when turning over or when springing up a shaft end formed as a square pin by 90 °. In addition, the radial play allows 27 a lighter assembly.

Between the insides 18 respectively. 19 the spring leg 8th and 9 the torque spring 7 is located as shown in 1 a here square-shaped pin formed 17 , The pin 17 is located on a front side of a second shaft end 4 ,

The front 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 located in the illustration according to 2 for example, square-shaped pin 17 , The axial length of the pin 17 , which is a first contact surface 24 and a second contact surface extending at right angles thereto 25 has, is by reference numerals 22 characterized. The pin 17 has a bevel 43 , which is a retraction of the pin 17 in the spring legs 8th respectively. 9 the torque spring 7 limited cavity 20 facilitated. The axial length 22 of the pin 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 formed.

When inserting the pin 17 in the cavity 20 the torque spring 7 are the opposing second contact surfaces 25 on the insides 18 respectively. 19 the spring leg 8th and 9 the torque spring 7 at. The width of the cavity 20 between the inner sides of the spring legs 8th and 9 the torque spring 7 is with reference numerals 11 characterized. From the illustration according to 2 is removable, that at the first shaft end 2 the receiving slots 12 respectively. 13 arranged in pairs and on the lateral surface section 3.1 located opposite.

Due to the selected geometry of the receiving slots 12 respectively. 13 , the axial length 23 the torque spring 7 and the axial extent 22 of the pin 17 , can provide an extremely small-sized coupling, in which the end face 5 of the second shaft end 4 the face 3 of the first shaft end 2 opposite.

A springing of the spring legs 8th respectively. 9 the torque spring 7 - For example, in the case of the transmission of an excessively high torque - is possible that the spring legs 8th respectively. 9 in a cavity 14 of the first shaft end 2 are admitted. A deformation, ie deflection of the spring legs 8th respectively. 9 inside the cavity 14 is thus guaranteed. Due to the spring characteristics 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 the axial length 23 , the torque spring 7 be given a certain elasticity. The formschlussfähig formed torque spring 7 can by variation or combination of the material thickness and the free length 26 the spring leg 8th respectively. 9 be set to the maximum torque to be transmitted.

As shown in 2 is the distance 11 in which the spring 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 pin 17 at the second end of the shaft 4 are thus on the insides 18 respectively. 19 the spring leg 8th respectively. 9 at. An axial relative movement of the pin 17 , ie the second shaft end 4 relative to the first shaft end 2 recorded torque spring 7 is due to the geometry of the cavity 20 between the first spring leg 8th and the second spring leg 9 readily 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 mutually coupled shaft ends.

From the illustration according to 3 it turns out that the front side 3 of the first shaft end 2 the end face of the second shaft end 4 opposite. The contact area is through the butt joint 6 educated. On the outside of Mantelmantelab section 3.1 of the first shaft end 2 are the spring leg ends 15 respectively. 16 recognizable, the outside of the lateral surface portion 3.1 of the first shaft end 2 a radial play 27 exhibit.

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

The second wave end 4 includes according to this embodiment, 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 chamfer 43 is trained. The bevel 43 allows easier insertion of the pin 17 in the cavity 20 the torque spring 7 taken from the spring legs 8th respectively. 9 is limited. According to this embodiment, the first longitudinal surface lie 29 or the second longitudinal surface 30 as a 2-edged system 28 trained pin 17 on the insides 18 respectively. 19 the torque spring 7 over the entire length. This embodiment favors a possible torsionally rigid formation 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 formed as a square.

The pin 17 at the second end of the shaft 4 includes opposing first contact surfaces 24 , as well as 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 out, which rounded in the front of the pin 17 passes. The front side 5 of the second shaft end 4 is the in 5 not shown, this opposite end face 3 of the first shaft end 2 across from.

6 shows an alternative embodiment variant of the shaft end with a pin having a hexagonal-shaped contour.

The pin 17 of the second shaft end 4 is as a six-edged system 32 executed. The embodiment of the second shaft end 4 according to 6 offers the advantage that an adjustability of an overload limit is made possible. The number of edges of the pins 17 the shaft end is inversely proportional to the overload limit.

7 shows a variant of the torque spring 7 with a receiving opening through the spring legs of the torque spring 7 molded investment sections is limited.

The in the 1 . 2 and 3 illustrated torque spring 7 may in a variant of a diamond-shaped receiving opening 36 include. In contrast to the representation of the torque spring 7 according to the embodiments in the 1 . 2 and 3 include 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 spring leg 8th and 9 is unlike the torque spring 7 according to the 1 . 2 and 3 not constant. The at the inn sides 18 respectively. 19 the spring leg 8th and 9 the torque spring 7 trained investment sections 39 . 40 . 41 and 42 limit in the respective spring leg 8th or 9 essentially triangular-shaped spaces. At the plant sections 39 . 40 respectively. 41 and 42 can either be the first contact surfaces 24 or the second contact surfaces 25 a pin 17 in 4-Kant-Anlage 31 according to 5 or the third or fourth contact surfaces 34 and 35 one in 6-Kant-Anlage 32 trained pin 17 of the second shaft end 4 issue. In terms of area, the contact surfaces correspond 24 . 25 of the pin 17 according to 5 as well as the surfaces of the third contact surface 34 and the fourth contact surface 35 the area size of the plant sections 39 . 40 respectively. 41 . 42 , The first face 37 and the second end face 38 the torque spring 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 to (compare 2 ) of the axial length 22 of the pin 17 at the second end of the shaft 4 , let him be in 4-Kant-Anlage 31 , let him be in 6-Kant-Anlage 32 educated. This is a maximum coverage of the contact surfaces 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 spring legs 8th respectively. 9 in the in 7 illustrated embodiment in leg areas 15 and 16 out.

With the proposed solution according to the invention can be a simple way create a few components comprehensive coupling, which requires a very small space and on the choice of material or the material thickness of the spring legs 8th respectively. 9 Sound-absorbing effect. The choice of material and the material thickness of the spring legs 8th respectively. 9 the torque spring 7 - in accordance with the 1 . 2 . 3 respectively. 7 - Illustrated embodiments, 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 embodiments in the 1 . 2 and 3 allows the compensation of a higher axial and Radial axis or angular offset of the shaft ends 2 and 4 to each other.

The torque spring 7 according to the representations in the 1 . 2 and 3 and as shown in 7 each has a bracket 10 opposite open end on. This allows a widening of the torque spring 7 in case of an impermissibly high torque. Thus, the transmission of an inadmissibly high torque can be counteracted. With the coupling proposed according to the invention 1 angular misalignments of several degrees and axial misalignments of several millimeters can be compensated. Become the components 2 . 4 and 7 the proposed coupling according to the invention 1 all made of the same material, these are largely insensitive due to the same coefficient of expansion against thermal expansion and cold shrinkage. Preference is given to the components of the coupling 1 made of steel according to the embodiments shown above.

With the coupling proposed according to the invention 1 can be, to give an example of application, equip asynchronous electric vehicle power steering systems.

1

clutch

2

first shaft end

3

front first wave 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 spigot 17

23

Axial length of the torque spring 7

24

first contact surface

25

second contact surface

26

free length of spring legs 8th . 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 (8)

Device for transmitting a torque from a first shaft end ( 2 ) to a second shaft end ( 4 ), with the shaft ends ( 2 . 4 ) are positively coupled with each other and with their end faces ( 3 . 5 ) are arranged facing each other and in a cavity ( 14 ) of the first shaft end ( 2 ) a torque spring ( 7 ), whose spring leg ( 8th . 9 ) with their inner sides ( 18 . 19 ) a receiving opening ( 20 . 36 ) for a pin ( 17 ; 28 . 31 . 32 ) on the second shaft end ( 4 ), wherein spring leg ends ( 15 . 16 ) of the torque spring ( 7 ) with respect to the spring legs ( 8th . 9 ) are angled and the first shaft end ( 2 ) with radial play ( 27 ), 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 ) for receiving the torque spring ( 7 ) are formed. Device according to claim 1, characterized in that the recesses ( 12 . 13 ) on the lateral surface section ( 3.1 ) are arranged in pairs opposite each other. Device according to claim 1, characterized in that the spring legs ( 8th . 9 ) of the torque spring ( 7 ) parallel to one another, a pick-up range ( 11 ) bounding insides ( 18 . 19 ) exhibit. Device according to claim 1, characterized in that the spring legs ( 8th . 9 ) of the torque spring ( 7 ) Investment sections ( 39 . 40 ; 41 . 42 ) having a receiving opening ( 36 ) within the torque spring ( 7 ) limit. Device according to claim 4, characterized in that the receiving sections ( 39 . 40 ; 41 . 42 ) of the spring leg ( 8th . 9 ) surface contact surfaces ( 24 . 25 ; 34 . 35 ) of the pin ( 17 ) of the second shaft end ( 4 ) correspond. Device according to claim 1, characterized ge indicates that the length ( 21 ) of the recesses ( 12 . 13 ) in the lateral surface section ( 3.1 ) the width ( 23 ) of the torque spring ( 7 ) corresponds. Device according to claim 1, characterized in that in the second shaft end ( 4 ) spring legs ( 8th . 9 ) of the torque spring ( 7 ) within the cavity ( 14 ) in a free length enabling a deflection ( 26 ). 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.