DE102013002039B4 - Double drive with rapid shutdown - Google Patents

Abstract

Double drive with quick shut-off for a work machine (1) with a shaft (6), especially agricultural or forestry machine, with a control device (5) for switching between a drive shaft (2) for the drive by an internal combustion engine and a drive shaft (3) an electric motor (4), characterized in that the shaft (6) of the working machine (1) is decoupled from the drive shaft (2) of the drive by the internal combustion engine and by a clutch (7) which is controlled by the control device (5) is coupled to the drive shaft (3) of the electric motor (4) by switching on the electric motor (4) and when an emergency stop switch (9) connected to the control device (5) is actuated, this switches off and a mechanical brake connected to the electric motor (4) (8) is controlled and switched on by the control device (5) and brings the machine (1) to a standstill.

Description

The invention relates to a double drive with rapid shutdown, for a work machine with the features of the preamble of claim 1.

Dual drives are used for forestry and agricultural machinery to be able to use either an internal combustion engine, such as a tractor, or an electric motor, depending on availability.

Because of the high risk of injury from the use of these machines with double drive a control device for switching between the drive shaft between a drive shaft with an internal combustion engine and a drive shaft of an electric motor with safety shutdowns is used in an emergency shutdown, however, resulting in the drive with internal combustion engines relatively long downtime and make the installation of complex safety technology necessary for electric motors, so that it is suitable for rough operation.

The object of the invention is therefore to substantially eliminate this significant disadvantage and to provide an arrangement in which particularly short downtime can be achieved both when using an electric motor and an internal combustion engine.

This object is achieved in a double drive of the type mentioned with the features of the characterizing part of claim 1.

The subclaims relate to particularly advantageous embodiments of the invention.

From the DE 29 46 547 A1 shows a double drive for a circular saw in a linear arrangement, in which between the directly driving electric motor and the PTO drive a jaw clutch for changing the drive type is arranged, which has the disadvantages described.

In the DE 10 2005 008 628 A1 is described a circular saw with a hydraulic drive, which is operated by electric motor or PTO, in which a braking device is installed in the hydraulic train, so that when triggered mechanically, the pressure line is disconnected and the energy is eliminated via an on-throttle. However, it is the case that this hydraulic brake can not stop the arrangement quickly enough with the braking effect sought by the invention.

The DE 695 34 282 T2 refers to an internal combustion engine driven concrete saw with an electromagnetic clutch and is otherwise adjacent to the concept of the invention.

The DE 34 27 733 A1 has a braking device for a portable or circular saw the object in which a brake acts on the saw blade and is actuated electromagnetically; Due to the arrangement, the braking force and thus the braking time is limited.

The US 2012/0 068 525 A1 also relates to a concrete saw, characterized by two cooperating internal combustion engines and their control and is thus far from the point.

In the double drive with quick shutdown for a machine whose shaft is uncoupled by a controlled by a control unit coupling of the drive shaft for driving by the engine and coupled to the drive shaft of the free-running electric motor.

When driven by the electric motor this is turned on via the control unit.

Upon actuation of an emergency stop switch connected to the control device, the electric motor is switched off and a directly connected mechanical brake is activated and switched on by the control device and the work machine is brought to a standstill.

With this arrangement, the downtime of a work machine compared to previous designs is shortened. When using an electric control device for driving and a mechanical brake on the electric motor and an electromagnetic clutch for operation on a circular saw, which has a particularly high risk of injury, the downtime is also reduced for operation with an internal combustion engine to three seconds, compared to fifteen seconds previously shown arrangements.

For the usual mode of operation in forestry and agriculture, the drive shaft for driving by the internal combustion engine, in particular a tractor, designed as a PTO, which is coupled via the clutch when switched on with the control unit with the shaft of the machine and disconnected when switching off the clutch , This creates a common connection option for the internal combustion engine of a tractor.

A simple, cheap and robust embodiment is to connect the coupling with the shaft of the working machine via a V-belt drive. The same applies to the connection of the shaft of the working machine via a V-belt drive with the drive shaft of the electric motor.

The control unit switches on the electric motor when the clutch is switched off, so that then the drive is made by this.

When the emergency stop switch is actuated, the control unit disengages the clutch and thus opens it and switches off the electric motor and the mechanical brake. This ensures that all drives are shut down and the brake can be fully effective in an emergency.

The electric motor and thus the work machine are braked by the mechanical brake to a standstill when it is turned on by the control unit. In this way, the mechanical brake is limited in effect on the smallest possible parts of the arrangement and the downtime is optimally reduced. The mechanical brake is to be adapted with the braking power to the kinetic energy of the working machine.

Convenient for shortening the downtime is when the mechanical brake, the electric motor and the clutch are electrically controlled by the control unit.

This means that the control device is designed as an electrical control device and the clutch is an electromagnetic clutch that has very short switching times.

Further advantages, features and possible applications of the present invention will become apparent from the following description in conjunction with the embodiments illustrated in the drawings.

In the specification, claims, and drawings, the terms and associated reference numerals used in the list of reference numerals below are used. In the drawing:

1 a working machine with double drive, with control unit, in an oblique view, schematically.

A circular saw as a working machine 1 is from a wave 6 powered by a double drive consisting of an electric motor 4 and an internal combustion engine is alternatively connected as a drive.

The internal combustion engine, such as a tractor, is optionally via a drive shaft designed as a PTO shaft 2 connected via a clutch 7 with a V-belt drive 10 connected to the shaft 6 drives.

When the drive is eliminated by an internal combustion engine, the clutch is a control device 5 activated and opened and the electric motor 4 activated and switched on. The electric motor 4 then drives with its drive shaft 3 via a V-belt drive 11 the wave 6 the working machine 1 at.

With the electric motor 4 is a mechanical brake 8th directly connected. When the emergency stop switch is actuated 9 on the control unit 5 this is done by activating the activation of the mechanical brake 8th and turning off the electric motor 4 if it is switched on, and switching off and thus opening the clutch 7 and disconnecting the drive shaft 2 ,

LIST OF REFERENCE NUMBERS

1

working machine

2

Drive shaft for driving by an internal combustion engine

3

Drive shaft of an electric motor 4

4

electric motor

5

control

6

Wave of the working machine 1

7

clutch

8th

mechanical brake

9

Emergency stop switch of the control unit 5

10

V-belt drive of the coupling 7

11

V-belt drive of the drive shaft 3 of the electric motor 4

Claims (10)

Double drive with quick shutdown for a working machine ( 1 ) with a wave ( 6 ), in particular agricultural or forestry machine, with a control device ( 5 ) for switching between a drive shaft ( 2 ) for driving by an internal combustion engine and a drive shaft ( 3 ) of an electric motor ( 4 ), characterized in that the shaft ( 6 ) of the working machine ( 1 ) by a coupling ( 7 ) supplied by the control device ( 5 ) is driven by the drive shaft ( 2 ) of the drive uncoupled by the internal combustion engine and to the drive shaft ( 3 ) of the electric motor ( 4 ) by switching on the electric motor ( 4 ) and when pressing one with the control unit ( 5 ) associated emergency stop switch ( 9 ) turns it off and one to the electric motor ( 4 ) connected mechanical brake ( 8th ) of the control device ( 5 ) is activated and switched on and the working machine ( 1 ) stops. Double drive according to claim 1, characterized in that the drive shaft ( 2 ) for the Drive through the internal combustion engine, in particular a tractor, is designed as a PTO shaft and via the clutch ( 7 ) when switching on with the control device ( 5 ) with the shaft of the working machine ( 1 ) is coupled and disconnected at shutdown of this. Double drive according to one of claims 1 or 2, characterized in that the coupling ( 7 ) with the wave ( 6 ) of the working machine ( 1 ) via a V-belt drive ( 10 ) connected is. Double drive according to one of claims 1 to 3, characterized in that the shaft ( 6 ) of the working machine ( 1 ) via a V-belt drive ( 11 ) with the drive shaft ( 3 ) of the electric motor ( 4 ) connected is. Double drive according to one of claims 1 to 4, characterized in that the electric motor ( 4 ) of the control device ( 5 ) is turned on when the clutch ( 7 ) is switched off. Double drive according to one of claims 1 to 5, characterized in that the electric motor ( 4 ) of the mechanical brake ( 8th ) is decelerated to a standstill when it is detected by the control device ( 5 ) is turned on. Double drive according to one of claims 1 to 6, characterized in that the control device ( 5 ) when the emergency stop switch ( 9 ) the coupling ( 7 ) turns off and thus opens and the electric motor ( 4 ) and the mechanical brake ( 8th ) turns on. Double drive according to one of claims 1 to 7, characterized in that the mechanical brake ( 8th ), the electric motor ( 4 ) and the coupling ( 7 ) from the control device ( 5 ) are electrically controlled. Double drive according to one of claims 1 to 8, characterized in that the control device ( 5 ) is an electrical control device. Double drive according to one of claims 1 to 9, characterized in that the working machine ( 1 ) is a circular saw.

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