DE102013002039A1 - Double drive for working machine e.g. circular saw for use in agriculture or forestry, has mechanical brake that is connected to motor and is switched on by operating control device to halt working machine - Google Patents

Abstract

The double drive has a control device (5) that is configured for switching between a drive shaft (2) to be driven by an internal combustion engine and a drive shaft (3) of an electric motor (4). A shaft (6) of a working machine (1) through a clutch (7), which is controlled by the control device of the drive shaft, is uncoupled from the engine and coupled to the drive shaft by turning the motor. An emergency OFF switch (9) is disabled and a mechanical brake (8) connected to the motor is switched on by operating the control device to halt the machine.

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 when using these machines with dual drive with quick shutdown is a control device for switching for the drive, between a drive shaft with an internal combustion engine and a drive shaft of an electric motor safety shutdowns are used, but 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 and, as well as claim 1, at the same time form part of the description of the invention.

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

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

When pressing one with the control unit ( 5 ) connected emergency stop switch this, the electric motor is switched off and controlled at this directly connected mechanical brake from the control unit and turned on and brought the machine to a halt.

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, as well as 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 in 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, inexpensive and robust embodiment is to connect the clutch to the shaft 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 output 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 working machine are braked by the mechanical brake to a standstill when 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.

An embodiment of the invention is described below.

It shows 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 are alternatively connected as a drive.

The internal combustion engine, such as a tractor, is optionally via a, designed as a PTO drive 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 output 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 output 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 ), from the drive shaft ( 2 ) of the drive uncoupled by the internal combustion engine and to the output shaft ( 3 ) 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 driving by 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 ) Work 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 output 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. and this Double drive according to one of claims 1 to 8, characterized in that the control device ( 5 ) is an electrical control device and the clutch is an electromagnetic clutch. 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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