DE102017116795A1 - Drive unit for a vehicle and vehicle with the drive unit - Google Patents

Abstract

In the case of bicycles or other muscle-powered vehicles, the driving force used is the muscular strength of the driver and possibly the passengers. Usually, the drive energy is introduced by the driver via a rotatable pair of pedals and forwarded, for example via a bicycle chain or other traction means on a driven wheel optionally with the interposition of a gearbox to the drive. Such bicycles or vehicles have brake systems which can be actuated, for example, by means of Bowden cables or hydraulic devices. The braking force is thereby optionally via a manual override or a foot control device, such as a coaster brake, initiated.Es proposed is a drive unit 2 for a vehicle 1, with a pedal system 4 for introducing a drive energy for the vehicle 1, wherein the pedal system a first pedal 5 and a second pedal 6 for generating an oscillating linear motion, with a brake 10 for braking the vehicle 1, and with a hydraulic system 11 for actuating the brake 10, wherein the hydraulic system 11, a first foot brake cylinder 12 and a second Foot brake cylinder 13, wherein the first foot brake cylinder 12 is the first pedal 5 and the second foot brake cylinder 13 associated with the second pedal 6, wherein the hydraulic system 11 in response to activation of the first and second foot brake cylinder 12,13 the brake 10 is actuated.

Description

The invention relates to a drive unit for a vehicle having the features of the preamble of claim 1. The invention further relates to a vehicle with this drive unit.

In the case of bicycles or other muscle-powered vehicles, the driving force used is the muscular strength of the driver and possibly the passengers. Usually, the drive energy is introduced by the driver via a rotatable pair of pedals and forwarded, for example via a bicycle chain or other traction means on a driven wheel optionally with the interposition of a gearbox to the drive. Such bicycles or vehicles have brake systems which can be actuated, for example, by means of Bowden cables or hydraulic devices. The braking force is selectively introduced via a manual override or a foot control device, such as a coaster brake.

Another type of drive for vehicles is given by oscillating actuated pedals. The publication DE 10 2015 210 775 A1 , which is arguably the closest prior art, discloses a pedal pedal device having a transmission assembly for driving a vehicle and a vehicle having the pedal device. The pedal pedal device has two pedals that are linearly oscillated to drive the vehicle.

The invention has for its object to provide an improved drive unit for a vehicle. This object is achieved by a drive unit with the features of claim 1 and by a vehicle having the features of claim 9. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims of the following description and / or the accompanying figures.

The invention relates to a drive unit for a vehicle, which is also designed for braking the vehicle. The vehicle may be an exclusively muscle-powered or a muscle-hybrid powered vehicle. In the exclusively muscle-driven vehicle, the drive energy is introduced exclusively via pedal forces. In a muscle-hybrid-powered vehicle, on the one hand, the drive energy is introduced via the pedal forces; for optional or permanent assistance, the drive unit has an electric machine. The vehicle can also be designed as a pure electric vehicle, wherein between the pedals and the driven wheels no mechanical drive connection is given, but the drive energy from the pedal forces is converted directly into electricity and drives the electric machine. Optionally, the electric machine can be used as an electric motor for driving or as a generator for recuperation of electrical energy. Optionally, the drive unit has a storage device for storing electrical energy for the electrical machine. Particularly preferably, the vehicle is designed as a four-wheel or as a tricycle or generally multi-wheel. In particular, the vehicle is designed as a light vehicle with a total mass of less than 500 kilograms, preferably less than 200 kilograms and in particular less than 100 kilograms.

The drive unit comprises a pedal system for introducing the drive energy, wherein the drive energy via the pedal forces, ie pedaling or pedaling, is initiated. In this case, the complete drive energy can be introduced via the pedal system or only part of the drive energy.

The pedal system includes a first and a second pedal. The pedal is designed in each case to be operated in particular by a foot of the driver so that the driver can drive the pedal system by means of the pedals. In each case a pedal force acts on the pedals through the driver's foot. The pedal system thereby forms an interface to the driver, so that the driver can operate this preferably with his feet and thus moves the pedal system and thereby initiates drive energy into the vehicle.

The pedals allow the generation of an oscillating linear movement, the pedals in a common direction of travel oscillating, but preferably in opposite directions, reciprocated. For example, the pedal system may include guide means such as e.g. a guide rail, have, which is designed for linear guidance of the two pedals in the direction of travel. Particularly preferably, both pedals have the same direction of travel. In particular, the first and the second pedal are each moved in a straight line, the rectilinear travel paths span a plane in which the direction of travel is. Particularly preferably, the two pedals are forcibly guided by the guide device in the direction of travel, in particular such that they have the single direction of freedom as the single degree of freedom, but are e.g. are locked perpendicular to the direction of travel.

The drive unit has a brake for braking the vehicle. For example, the brake may act on a wheel of the vehicle. The brake is designed in particular as a hydraulic brake and is actuated via a hydraulic line. In particular, the brake has at least a brake cylinder as a working cylinder, wherein the brake cylinder is driven via the hydraulic line to actuate the brake.

The drive unit has a hydraulic system for actuating the brake. The hydraulic system comprises the hydraulic line, which is designed in particular as a secondary circuit.

In the context of the invention, it is proposed that the hydraulic system has a first foot brake cylinder and a second foot brake cylinder. Under a foot brake cylinder is understood in particular a combination of a piston and a cylinder, wherein the piston is arranged to be movable in the cylinder. By actuating the piston, a hydraulic fluid in the cylinder can be pressurized and / or transported. The first foot brake cylinder is the first pedal, the second foot brake cylinder is assigned to the second pedal and / or associated. In particular, it is provided that the associated foot brake cylinder is actuated by pedaling the pedal. It is envisaged that the hydraulic system actuates the brake in response to activation of the first and second foot brake cylinders.

In particular, an actuation of the foot brake cylinder is understood as an application of an actuating force or pedal force and / or an activation of the foot brake cylinder as a pressure build-up in the foot brake cylinder. An actuation is thus a precursor to the activation of the foot brake cylinder. Optionally, and as stated later, it may be provided that a minimum actuation force is required to activate the foot brake cylinder. In this preferred development, the foot brake cylinder is thus initially actuated with a force which is smaller than the minimum actuation force, and the foot brake cylinder is activated only with a force which is greater than the minimum actuation force.

It is a consideration of the invention, the drive unit in such a way that the driver via the pedal system can initiate a braking operation. This allows the driver to brake the vehicle without the help of his hands. Conventional bicycles such a braking operation on the so-called coaster brake is known. However, a transmission of such a mechanism to the vehicle with the drive unit is not possible because there is no resignation in this way. Instead, a corresponding brake command is initiated via the foot brake cylinder and forwarded to the brake. In this way, an intuitive braking with the feet can also be implemented in an oscillating operated pedal system.

In a preferred embodiment of the invention, the hydraulic system is designed to trigger the braking process, when the foot brake cylinder, a simultaneous actuation and / or initiation of pedal forces is converted to the pedals and / or these are activated at the same time. In the oscillating pedal system, the pedal forces are alternately introduced into the first and the second pedals in a conventional drive operation. A simultaneous introduction of pedal forces, however, leads to a blockage of the pedal system. The hydraulic system detects the simultaneous actuation, converts it (mechanically) into a braking request and triggers the braking process of the brake. In this way, the driver can trigger a braking intuitively over the feet.

In one possible constructional realization, the hydraulic system has a master cylinder arrangement, wherein both foot brake cylinders are hydraulically and / or fluidically connected to the master cylinder arrangement via a common foot primary circuit. In particular, the outputs of the two foot brake cylinders in the common Fußprimärkreis are fluidically and / or hydraulically and / or communicating with each other. A pressure introduced by the foot brake cylinder is thus forwarded to the master cylinder arrangement on the one hand and to the other foot brake cylinder on the other hand. In the event that only one foot brake cylinder is activated and the other foot brake cylinder is inactive, the pressure from the activated foot brake cylinder via the Fußprimärkreis is forwarded to the other foot brake cylinder, which reduces the pressure. In the event that both foot brake cylinders are activated, they can not mutually relieve the pressure, so that the pressure is applied to the master cylinder assembly and the brake is applied. The fluidic coupling of the two foot brake cylinders in the Fußprimärkreis is thus hydraulically implemented that the master cylinder assembly and / or the brake is only pressurized when both Fußbremszylinder are activated.

In a preferred structural embodiment, the Fußbremszylinder each have a cylinder outlet, wherein the Fußprimärkreis is formed as a hydraulic line, which two inputs, which are fluidically and / or hydraulically connected to the cylinder outputs, and an output, wherein the output with the master cylinder assembly fluidically and / or hydraulically connected. Thus, the Fußbremszylinder communicate via the Fußprimärkreis with each other fluidically and / or reduce the pressure on each other.

In a preferred development of the invention, the hydraulic system has a compensation arrangement. Each of the foot brake cylinders is hydraulically connectable with the balancing assembly. The hydraulic system is designed such that the foot brake cylinders are each hydraulically and / or fluidically isolated from the compensation arrangement in an activated state and are hydraulically and / or fluidically connected in an inactive state with the compensation arrangement. In particular, at least one of the foot brake cylinders in the partially actuated state is hydraulically and / or fluidically connected to the compensation arrangement, so that the applied pressure can be diverted from the activated foot brake cylinder into the compensation arrangement. The compensation arrangement can be designed as a common compensation arrangement for both foot brake cylinders. In particular, this has a common reservoir for both foot brake cylinder. In a preferred embodiment, the compensation arrangement for each foot brake cylinder has its own reservoir. Such combinations of reservoir and brake cylinder are known in principle for example from motorcycle technology as a foot brake.

In a preferred embodiment of the invention, the foot brake cylinders are each biased to accommodate a minimum force in the operation of the foot brake cylinder without activation of the foot brake cylinder can. The minimum force is configured, for example, as minimum actuation force such that it is formed by the force which is generated when the driver's foot is laid down on a pedal. This minimum force makes sense, so that during normal operation no unwanted braking operation is triggered. In addition, the minimum force may still include a safety value and / or other offset values. The safety value and / or the other offset values can be added to the above force to form a threshold value as a minimum force. The addition of the safety value and optionally the other offset values will prevent unintentional braking from being triggered by only a slight application of force to the pedals beyond normal operation. Such a situation could be, for example, when the driver straightens on the vehicle and puts his feet on the pedals. The safety value and / or the offset values can or can be determined empirically.

By the hydraulic system is achieved that the amount of braking force in the braking operation in dependence on the height of the first and / or the second pedal force. The braking operation is therefore carried out depending on the height of the pedal forces. Exceeding the pedal forces, for example, the threshold / limit and / or the minimum force to a large extent, so a strong braking is performed, the pedal forces exceed the threshold / limit and / or the minimum force only to a small extent, so a weak braking is performed. The correlation between the magnitude of the braking force and the magnitude of the pedal forces may be empirically determined or scientifically calculated and implemented constructively in the hydraulic system.

The drive unit preferably comprises a conversion module which is coupled to convert the oscillating linear movement into a rotational movement of at least one wheel of the vehicle to the pedal system. The conversion assembly is configured to process the oscillating linear motion from the movement of the driver. The reaction module is operatively connected to the pedal system and takes over the oscillating linear motion and converts it into a rotational movement of at least one wheel of the vehicle. In one possible embodiment of the invention, the reaction assembly has a pedal traction device, which is guided around at least a first and a second deflection roller. Preferably, the pedal traction device rotates around the at least first deflection roller and the at least second deflection roller. The pedal force applied by the driver can be used, for example, on one of the deflection rollers for propulsion of the vehicle, for example by means of an arranged output shaft. The pedal traction means may e.g. be designed as a rope or belt. In a further possible embodiment, the conversion module is designed as or comprises the electric machine, which can be used both as a generator and as an electric motor for driving the vehicle.

In a preferred development of the invention, the master cylinder arrangement has a summing unit and a distributor unit. It is envisaged that the foot brake cylinder and / or the Fußprimärkreis are hydraulically connected to the summing unit and / or the distribution unit is hydraulically connected to the brake.

Optionally additionally, the drive unit has a hand brake cylinder, which can be actuated by the driver's hand. The hand brake cylinder is hydraulically and / or fluidically connected via a hand primary circuit with the master cylinder arrangement, in particular with the summation unit of the master cylinder arrangement. By the hand brake cylinder is given a further possibility for braking, so that the driver can press either the foot brake cylinder or the hand brake cylinder at a braking request.

Another object of the invention is a vehicle having a drive unit, as described above. The vehicle is in particular designed as described above.

• 1 schematisch ein Fahrzeug mit einer Antriebseinheit als ein Ausführungsbeispiel der Erfindung;
• 2 schematisch das hydraulische System in der Antriebseinheit in der 1.

Further features, advantages and effects of the invention will become apparent from the following description of a preferred embodiment of the invention and the accompanying figures. These show:

• 1 schematically a vehicle with a drive unit as an embodiment of the invention;
• 2 schematically the hydraulic system in the drive unit in the 1 ,

1 shows a schematic diagram of a vehicle 1 with a drive unit 2 to drive the vehicle 1 , In the vehicle 1 it can be an exclusively muscle-powered or muscle-hybrid-powered or electric vehicle, ie a vehicle 1 which has an electric machine for optional or permanent support of the drive. The vehicle 1 has four wheels in the embodiment 3 on, with two wheels 3 a driven axle and two wheels 3 associated with another axis. The vehicle 1 thus has two driven wheels 3 on.

The drive unit 2 has a pedal system 4 for generating an oscillating linear motion. The pedal system 4 includes a first pedal 5 and a second pedal 6 , The pedals 5 . 6 form an interface to the driver and provide a support surface for the driver's foot. The pedals 5 . 6 are arranged for linear guidance in a guide device. The guide device is as a guide rail 7 educated. By the driver, the pedals 5 , 6 exerting a pedal force on the pedals 5 . 6 oscillating and also moved in opposite directions, so that the oscillating linear motion is generated.

The drive unit 2 includes an implementation assembly 8th which is used to convert the oscillating linear movement into a rotational movement of at least one of the wheels 3 of the vehicle 1 serves.

In the in the 1 In the embodiment shown, the transmission of the oscillating linear movement to the reaction module takes place 8th and their implementation in the rotational movement via a Pedalzugmittel 9 on which the first pedal 5 and the second pedal 6 are arranged. The pedal traction device 9 can be designed as a rope. By the pedal traction device 9 are the pedals 5 . 6 coupled together. This coupling is preferably accomplished via at least two deflection rollers (not shown) via which the pedal traction means 9 is diverted.

The drive unit 2 has a brake 10 on, on at least one of the wheels 3 coupled or is operatively connected to this. This is hydraulically formed. By means of the brake 10 can be a braking operation, in which the vehicle 1 comes to a stop or is slowed down. The brake 10 can - as shown - on the driven wheels 3 and / or at the non-driven wheels 3 be arranged.

The drive unit 2 has a hydraulic system 11 on which for the operation of the brake 10 serves. The hydraulic system 11 has a first foot brake cylinder 12 and a second foot brake cylinder 13 on. The first foot brake cylinder 12 is with the first pedals 5 connected so that with the actuation of the first pedals 5 at the same time the first foot brake cylinder 12 is pressed. The second foot brake cylinder 13 is with the second pedals 6 connected so that with the actuation of the second pedals 6 at the same time the second foot brake cylinder 13 is pressed. The hydraulic system 11 also has a master cylinder arrangement 14 on. The first and the second foot brake cylinder 12 . 13 are about a Fußprimärkreis 15 with the master cylinder assembly 14 connected hydraulically and / or fluidically. The foot primary circle 15 has two entrances 16 a, b, which hydraulically and / or fluidically with the Fußbremszylindern 12 . 13 are connected, as well as an output 17 on, which with the master cylinder assembly 14 hydraulically and / or fluidically connected. The hydraulic system 11 has a secondary circuit 18 on, being an entrance 19 of the secondary circuit 18 fluidically and / or hydraulically with the master cylinder assembly 14 is connected and being an output 20 of the secondary circuit 18 fluidically and / or hydraulically with the brake 10 connected is.

The braking function of the drive unit 2 is designed so that in a simultaneous operation, in particular, sufficiently strong operation, both foot brake cylinder 12 . 13 so both foot brake cylinders 12 . 13 be activated at the same time, the brake 10 is pressed to the vehicle 1 to break. The strength of the braking depends on the strength of the operation of the foot brake cylinder 12 . 13 , To accidentally press the brake 10 To avoid the foot brake cylinder 12 . 13 be biased for example by means of a spring device, so that only after exceeding a minimum force limit as an operation of the foot brake cylinder 12 . 13 as activation of the foot brake cylinder 12 . 13 is implemented. Optionally, further offset values can be included in the minimum force or in the limit value for example, to interpret 1 two-legged support of the driver not accidentally as a braking request.

The 2 shows a schematic block diagram of the hydraulic system 11 , The hydraulic system 11 In the illustrated exemplary embodiment, the two foot brake cylinders are shown 12 . 13 on, but may - as indicated by dashed lines - also have further actuating cylinder, such as a hand brake cylinder, which by a driver of the vehicle 1 can be operated by hand. The further actuating cylinder is then constructed like the manual actuating cylinder of a motorcycle and has a hand lever which acts on a piston which is arranged in a cylinder, so that a hydraulic pressure can be built up.

Each of the foot brake cylinders 12 . 13 is with a surge tank 21 respectively. 22 connected, which makes it possible, a volume balance in a hydraulic fluid in the Fußbremszylindern 12 . 13 to accomplish. The expansion tank 21 . 22 are like that with the foot brake cylinders 12 . 13 hydraulically connected, that in an unactuated state, a volume compensation, in the actuated state, however, the surge tank 21 . 22 from the respective foot brake cylinder 12 . 13 is disconnected so that it can build up hydraulic pressure. The expansion tank 21 . 22 together form a balancing arrangement 23 ,

The foot brake cylinder 12 . 13 build the hydraulic pressure in the foot primary circle 15 on, as already stated in the 1 was explained. In the Fußprimärkreise 15 There is hydraulic fluid to transmit the pressure.

On the output side is the Fußprimärkreis 15 hydraulically with the master cylinder assembly 14 connected. In particular, the Fußprimärkreis 15 with a summation unit 24 the master cylinder assembly 14 connected. The master cylinder assembly 14 also has a distribution unit 25 on, on which are two secondary circuits 18 connect. The summation unit 24 and the distribution unit 25 For example, they are designed as two chamber areas, which are coupled to each other via a movable piston. Will the pressure in the summation unit 24 increases, the piston is displaced and a pressure in the distributor unit 25 elevated. The chamber regions may each have one or more chamber sections. Optionally, other secondary circuits can 18 be provided. The secondary circuits 18 are arranged hydraulically parallel to each other. The secondary circuits 18 are each with a working cylinder of the brake 10 coupled hydraulically, so that a hydraulic pressure from the master cylinder assembly 14 to the working cylinders and thus to the brake 10 can be routed and this can be operated. The working cylinders are designed for example as a brake cylinder. The master cylinder assembly 14 is with another reservoir 26 hydraulically connected.

The foot brake cylinder 12 . 13 are thus hydraulically with each other and with the master cylinder assembly 14 , in particular with the summation unit 24 the master cylinder assembly 14 , connected. When pedaling only a foot brake cylinder 12 . 13 operated, the hydraulic fluid is in a surge tank 21 . 22 of the other pedal 5 . 6 associated foot brake cylinder 13 . 12 shifted, so no pressure in the hydraulic system 11 is built. Only if the second pedal 6 . 5 is pressed, the hydraulic fluid is no longer in the foot brake cylinder 12 . 13 associated surge tanks 21 . 22 flow, so that a brake pressure is built up and by means of the summation unit 24 on the brake 10 of the vehicle 1 acts. By means of, for example, a return spring as a spring device, a minimum pedal force can be set as a minimum force to prevent inadvertent actuation of the brake 10 to avoid.

LIST OF REFERENCE NUMBERS

1

vehicle

2

drive unit

3

bikes

4

pedal system

5

first pedals

6

second pedals

7

guide rail

8th

implementation package

9

Pedalzugmittel

10

brake

11

hydraulic system

12

first foot brake cylinder

13

second foot brake cylinder

14

Master cylinder assembly

15

Fußprimärkreis

16a, b

Entrances of the Fußprimärkreises

17

Exit of the foot primary circle

18

secondary circuit

19

Input of the secondary circuit

20

Output of the secondary circuit

21

surge tank

22

surge tank

23

compensation arrangement

24

summing

25

distribution unit

26

additional reservoir

FROM

directions

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015210775 A1 [0003]

Claims (9)

Drive unit (2) for a vehicle (1), comprising a pedal system (4) for introducing drive energy for the vehicle (1), wherein the pedal system (4) comprises a first pedal (5) and a second pedal (6) for generating a oscillating linear motion, comprising a brake (10) for braking the vehicle (1), characterized by a hydraulic system (11) for actuating the brake (10), wherein the hydraulic system (11) comprises a first foot brake cylinder (12) and a second Foot brake cylinder (13), wherein the first foot brake cylinder (12) the first pedal (5) and the second foot brake cylinder (13) is associated with the second pedal (6), wherein the hydraulic system (11) in response to activation of the first and second foot brake cylinder (12,13), the brake (10) is actuated. Drive unit (2) after Claim 1 , characterized in that the hydraulic system (11) is adapted to actuate the brake (10) when at the same time the first and the second foot brake cylinder (12, 13) are activated. Drive unit (2) after Claim 1 or 2 , characterized in that the hydraulic system (11) comprises a master cylinder assembly (14), wherein the foot brake cylinders (12, 13) via a common Fußprimärkreis (15) to the master cylinder assembly (14) are hydraulically connected. Drive unit (2) according to one of the preceding claims, characterized in that the foot brake cylinders (12, 13) with a compensation arrangement (23) are hydraulically connectable, wherein the foot brake cylinder (12,13) in an activated state of the compensating assembly (23) hydraulically are isolated and hydraulically connected in an inactivated state with the balancing assembly (23). Drive unit (2) after Claim 4 , characterized in that in a partially actuated state, wherein only one foot brake cylinder (12,13) is activated and the other foot brake cylinder (13,12) is inactive, both foot brake cylinders (12,13) via the Fußprimärkreis (15) with the balancing arrangement ( 23) are hydraulically connected. Drive unit (2) according to one of the preceding claims, characterized in that the foot brake cylinders (12, 13) are prestressed in order to be able to absorb a minimum force without activation of the foot brake cylinder (12, 13) when the foot brake cylinders (12, 13) are actuated. Drive unit (2) according to one of the preceding claims, characterized in that the hydraulic system (11) comprises a summing unit (24) and a distributor unit (25), wherein the foot brake cylinder (12,13) and / or the Fußprimärkreis (15) with the summing unit (24) are hydraulically connected and / or the distributor unit (25) is hydraulically connected to the brake (10). Drive unit (2) after Claim 7 characterized by a handbrake cylinder, wherein the handbrake cylinder is hydraulically connected via a hand priming circuit to the summing unit (25). Vehicle (1), characterized by a drive unit according to one of the preceding claims.

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