DE102018003643B3 - Curve-controlled step transmission - Google Patents

Abstract

The invention relates to a drive system for generating rotary step movements, comprising a coupling structure (3), a drive crank (1), an output crank (2) and an associated cam (4), wherein the coupling structure (3) consists of two gear elements (5). and (7) and the connection of at least one cam roller (9) and the gear member (5) with the output crank (2), the gear member (7) with the drive crank (1) and the gear member (5) with the gear member (7). are hingedly connected. The object of the invention is to develop a drive system that increases the life of the transmission and drastically reduces the cycle time. This object is achieved in that by the rotating drive crank (1) via the coupling structure (3) and a fixed cam (4) a step movement on the output crank (2) is generated and that at several, but at least two stations (resting phases) at least two coupling structures (3) are used, wherein drive crank (1) and driven crank (2) extend coaxially and thus have a common axis of rotation (6).

Description

The invention relates to a drive system according to the preamble of claim 1.

State of the art

Known step transmission of this type contain a rotatably mounted within a housing and driven by a motor cam element having a switching curve with a switching range and a locking range. In the housing also, for example, a disc-shaped output element is mounted, which contains a plurality of cam rollers for engagement with the guide cam of the cam member. The cam rollers roll on the running surfaces of the switching curve, wherein the switching curves in the conventional transmissions conventionally have a switching range with a predetermined slope and a latching area without slope. As a result, a linearly continuous drive movement is converted into a nonlinear continuous latch-in-latching movement. This detent-in-rest movement consists of step and detent phases that are optimally adapted to the respective production process with the help of the movement design. Determining the cycle time and the associated output of the system is on the one hand, the duration of the process-related longest processing step, which takes place during the resting phase. On the other hand, the shortest possible step phase is desired, since in this time only the transport of the goods from station to station takes place without actual added value. The ratio of step phase to rest phase significantly influences the dynamic behavior.

Curve-controlled drive concepts are reliable, process-reliable and mechanically-inevitable, but they do not allow a change in the number of stations or the movement function. This means that you can not change the step and lock phases. These specifications are precisely defined by the cam cylinder.

Drive systems of the type mentioned are out DE 30 27 402 A1 known.

Task setting

Presentation of the invention

The object of the invention is to develop a drive system that increases the life of the transmission and drastically reduces the cycle time. This is achieved in a rotary indexing table or step transmission of the type mentioned by the characterizing features of claim 1.

In comparison to known rotary indexing tables, the drive system according to the invention is driven by a novel mechanical basic structure. The peculiarity of the invention is firstly in the fixed inner curve contour, whereby only the coupling transmission components are moved. As a result, the proportion of moving masses is significantly reduced, whereby the dynamic loads are significantly reduced. Another special feature of the present innovation is the extension of the kinematics by the duplication of the mechanical structure for symmetrical load distribution. Due to this symmetrical load distribution, a significant reduction of the cycle time can be achieved in comparison to known cam-controlled drive concepts. According to claim 1, the drive system according to the invention consists of a coupling structure ( 3 ), a drive crank ( 1 ), a driven crank ( 2 ) with associated cam disc ( 4 ). The coupling structure ( 3 ) consists of two gear elements ( 5 ) and ( 7 ) and the connection of at least one cam roller ( 9 ), wherein the gear member ( 5 ) with the output crank ( 2 ) and the gear member ( 7 ) with the drive crank ( 1 ) is hinged. The drive crank ( 1 ) is therefore connected to the gear member ( 7 ) via a rotary joint ( 12 ), the output crank ( 2 ) with the gear member ( 5 ) via another rotary joint ( 10 ) and the two gear members ( 5 ) and ( 7 ) are also via a swivel joint ( 11 ) connected. The rotating drive crank ( 1 ) generated via the coupling structure ( 3 ) and the fixed cam ( 4 ) a step movement on the output crank ( 2 ). At least two coupling structures (at least two stations (latching phases) 3 ), wherein at least one of the transmission elements ( 5 ) or ( 7 ) with at least one cam roller ( 9 ) connected is.

The drawings according to 4 to 12 make it clear that the new drive system can serve several stations (latching phases), but at least two stations, as also expressed in claim 2. The figures show the step transmission of three to eight stations with different number of cam rollers ( 9 ).

According to claim 3, the respective step phase does not have to be identical to the preceding one.

The drive crank ( 1 ) and the output crank ( 2 ) have according to claim 1, a common axis of rotation ( 6 ) and are connected to each other in stock.

According to claim 4, the cam ( 4 ) formed as a groove curve, in whose groove ( 8th ) the cam rollers ( 9 protrude).

The cam ( 4 ) may also have the shape of an inner or outer bead curve instead of the groove curve, with two each Cam rollers ( 9 ) on both sides inside or outside positively abut the bead and roll, as formulated in claim 5.

According to claim 6, the drive crank ( 1 ) and the output crank ( 2 ) be disc-shaped.

list of figures

• 1 Schematic representation of the novel drive concept with designation of the gear elements - Three-dimensional view
• 2 Schematic representation of the novel drive concept with designation of the gear elements - side view
• 3 Schematic representation of the novel drive concept with designation of the gear elements - view from above
• 4 Schematic representation of step transmission with three stations, three cam rollers
• 5 Schematic representation of stepper with four stations, four cam rollers
• 6 Schematic representation of stepper with five stations, five cam rollers
• 7 Schematic representation of stepper with six stations, two cam rollers
• 8th Schematic representation of step gear with six stations, three cam rollers
• 9 Schematic diagram of step gear with six stations, six cam rollers
• 10 Schematic diagram of step gear with eight stations, two cam rollers
• 11 Schematic representation of stepper with eight stations, four cam rollers
• 12 Schematic diagram of stepper gear with eight stations, eight cam rollers

The drive system according to the invention for generating rotary step movements consists of a coupling structure ( 3 ), a drive crank ( 1 ), a driven crank ( 2 ) and an associated cam ( 4 ). The coupling structure ( 3 ) consists of two gear elements ( 5 ) and ( 7 ) and connection of at least one cam roller ( 9 ), wherein the gear member ( 5 ) with the output crank ( 2 ), the transmission element ( 7 ) with the drive crank ( 1 ) and the gear member ( 5 ) with the gear member ( 7 ) is hinged. The rotating drive crank ( 1 ) generated via the coupling structure ( 3 ) and the fixed cam ( 4 ) a step movement on the output crank ( 2 ). The decisive factor is that the cam disc ( 4 ) stands still. This significantly reduces the proportion of moving masses. The drive crank ( 1 ) is via the fixed cam ( 4 ) and the drive crank ( 2 ) stored. As a result, the installation space of the transmission is reduced because the drive crank ( 1 ) and output crank ( 2 ) are stored one inside the other. You have a common axis of rotation ( 6 ). The gear member ( 5 ) is with the output crank ( 2 ) via a rotary joint ( 10 ) connected. The gear member ( 7 ) is also via a rotary joint ( 11 ) with gear member ( 5 ) connected. About another rotary joint ( 12 ) is the transmission element ( 7 ) with the drive crank ( 1 ) connected. At the gear member ( 7 ) is finally the cam roller ( 9 ) appropriate.

Conversely, the cam roller ( 9 ) also on the gear member ( 5 ) to be appropriate. This depends on the embodiment of the drive system according to the invention. In the drive system according to the invention, the cam rollers ( 9 ) constant at the cam ( 4 ) and are constantly and evenly in use. The force on the cam rollers ( 9 ) is always distributed equally. There is no stop of the cam rollers ( 9 ) as in the known rotary indexing gearboxes. This causes the life of the cam rollers ( 9 ) and thus the overall transmission is increased. The customer-specific indexing plate with the respective number of stations is connected to the output crank ( 2 ) connected.

The number of coupling structures ( 3 ) is defined by the number of stations (resting phases). This is illustrated by the 4 - 12 , The peculiarity of the drive system according to the invention lies in the fact that, with the number of stations stationed (latching phases) being the same, the number of cam followers ( 9 ) can be reduced. The reason for this is the symmetrical arrangement of the coupling structures ( 3 ). The number of coupling structures ( 3 For example, at 8th Stations either 8th as with known rotary indexing drives, but also 4 or 2 , at 6 Stations either 6 (Prior art), but also 3 or 2 , at 4 Stations either 4 (Prior art) or 2 ,

For non-symmetric number of stations such as 3 . 5 . 7 or 11 can the number of cam rollers ( 9 ) also reduced and the symmetry are exploited. For example 7 Stations can 6 or 3 Coupling structures ( 3 ) are used and the remaining are then as in the number of symmetrical stations blanks. Here, due to the asymmetrical station division, a slight increase in the load on the drive crank ( 1 ).

LIST OF REFERENCE NUMBERS

1

drive crank

2

output crank

3

coupling structure

4

cam

5

transmission member

6

axis of rotation

7

transmission member

8th

groove

9

follower

10

Swivel joint between gear member ( 5 ) and output crank ( 2 )

11

Swivel joint between gear member ( 5 ) and gear member ( 7 )

12

Swivel joint between gear member ( 7 ) and drive crank ( 1 )

Claims (6)

Drive system for generating rotary step movements, consisting of a coupling structure (3), a drive crank (1), a driven crank (2) and an associated cam (4), wherein the coupling structure (3) consists of two gear members (5) and (7) and the connection of at least one cam roller (9) and the gear member (5) with the output crank (2), the gear member (7) with the drive crank (1) and the gear member (5) are pivotally connected to the gear member (7), characterized in that by the rotating drive crank (1) via the coupling structure (3) and a fixed cam (4) a step movement on the output crank (2) is generated and that at several, but at least two stations (latching phases) at least two coupling structures (3) are used, wherein drive crank (1) and driven crank (2) extend coaxially and thus have a common axis of rotation (6). Drive system after Claim 1 , characterized in that the step transmission as many, but at least two stations (rest phases) can operate. Drive system after Claim 1 and 2 , characterized in that the following step phase need not be identical to the previous step phase. Drive system after at least one of Claims 1 to 3 , characterized in that the cam disc (4) is designed as a cam groove in the groove (8) protrude the cam rollers (9) and roll there. Drive system after at least one of Claims 1 to 3 , characterized in that the cam disc (4) is formed as an internal or external bead curve and that in each case two cam rollers (9) on either side either inside or outside positively abut the bead and roll. Drive system according to at least one of the preceding claims, characterized in that the drive crank (1) and the driven crank (2) are disc-shaped.

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