WO2008073025A1

WO2008073025A1 - Gearshift control

Info

Publication number: WO2008073025A1
Application number: PCT/SE2007/050849
Authority: WO
Inventors: Torbjörn JANSSON; Hilding Nilsson
Original assignee: Scania Cv Ab (Publ)
Priority date: 2006-12-14
Filing date: 2007-11-15
Publication date: 2008-06-19
Also published as: EP2094994A4; SE0602699L; EP2094994A1; SE530676C2

Abstract

The present invention relates to a solution for controlling a gear- b o x in a motor vehicle, wherein a gearshift lever (100) of a control device is movable between at least two gear positions (A, B, C, D, E, F). An energy emitter means (115) at a distal end (112) of the lever (100) emits a lever signal representative of the location of the lever (100), and a transducer matrix (120) is configured to contactlessly detect the lever signal. In response to this signal, the transducer matrix (120) produces a data signal (d), which depending on the lever's (100) location, may be indi- c a t i v e of the gear positions (A, B, C, D, E, F) as well as at least one intermediate position (210, 220, 230) located on a path (P) between at least one first and at least one second position of the gear positions (A, B, C, D, E, F). A central unit (140) receives the data signal (d), and in response thereto, generates a control signal (S gear ) and at least one gearbox parameter (P g e a r ). The control signal (S g e a r ) represents a gear to be engaged in the gearbox, and the at least one gearbox parameter (P g e a r ) is adap- t e d to control at least one characteristic of the gearbox other than the gear to be engaged, e.g. a freewheel-clutch operation, and/or a gear-synchronization in respect of an estimated future gear to be engaged.

Description

Gearshift Control

THE BACKGROUND OF THE INVENTION AND PRIOR ART

The present invention relates generally to gear-shifting solutions for motor vehicles. More particularly the invention relates to a gearshift control device according to the preamble of claim 1 and a motor vehicle according to claim 7. The invention also re- lates to a method of controlling gear changes in a gearbox of a motor vehicle according to the preamble of claim 8, a computer program according to claim 12 and a computer program product according to claim 13.

Conventionally, gearshift levers have been designed to influence the gearbox of a motor vehicle exclusively by mechanical measures. This means that there is an unbroken physical link from the lever's operator handle to the gearbox members that cause a previous gear to be disengaged, and subsequently a desired new gear to be engaged. This type of design may be prob- lematic for many reasons, especially if the gearbox is complex, for instance including many gears and/or gear ranges, and/or if the driver cabin is relatively remote from the gearbox.

Therefore, various alternative designs have been developed, wherein control commands are generated by the gearshift lever and transmitted to the gearbox by other means than mechanical. The U. S. patent No. 5,852,953 describes one example of such a solution. Here, a gearshift control unit is used, which produces gearshift control signals of an electronic format. A plurality of optical, or magnetic, sensors are disposed adjacent of each shif- ting position of the gearbox. A sensor for a particular gear produces a gearshift signal in respect of this gear if a manually operable lever of the control unit is positioned at a designated location being associated with the gear. However, the sensors are exclusively configured to detect whether the lever is positioned at one of the designated gear positions.

The U. S. patent No. 6,232,959 discloses a control device for positioning and control of a cursor on a computer screen. The device has a finger, or hand, grippable member, which is resi- liently mounted on a plate support, such that the grippable member returns to a neutral position whenever released from the user's grip. A laser beam is emitted from an element linked to the grippable member, and the laser beam is directed towards addressable sensor arrays. Position information for controlling the cursor is then derived based on signals generated by the addressable sensor arrays. Although this design may provide a useful interface when manipulating graphical objects on the screen of a standard computer, the solution is not well suited for controlling transmission related parameters of a motor vehicle.

SUMMARY OF THE INVENTION

The object of the present invention is therefore to provide a so- lution, which offers a cost-efficient, flexible and reliable control means for a gearbox in a motor vehicle.

According to one aspect of the invention, the object is achieved by the initially described system, wherein the plurality of sensors include a transducer matrix. This component, in turn, is configu- red to detect at least one intermediate position of the gearshift lever, where the at least one intermediate position is located on a path between at least one first and at least one second position of the gear positions. The transducer matrix is further adapted to include information reflecting the at least one intermediate position in the data signal produced in response to a lever signal representative of the location of the gearshift lever. A central unit is adapted to receive the data signal, and in response thereto, generate at least one gearbox parameter adapted to control at least one characteristic of the gearbox other than a gear to be engaged. This control device is advantageous in that enables efficient operation of the gearbox. Namely, based on the order in which the gearshift lever passes certain intermediate non-gear positions, the gearbox parameters can be adapted to prepare the gearbox in advance for appropriate events, such as freewheel- clutch operations, and/or a gear-synchronization in respect of an estimated future gear to be engaged. The function of the gearshift lever may also be monitored continuously, or repeatedly. Moreover, the design is flexible with respect to different gear- shift patterns and the number of gears in the gearbox.

According to one embodiment of this aspect of the invention, the at least one gearbox parameter is specifically adapted to cause a freewheel-clutch operation and/or a gear-synchronization in respect of an estimated future gear to be engaged. Thus, the gearbox can be operated quicker, and new gears can be engaged more efficiently.

According to another embodiment of this aspect of the invention, the energy emitter means includes at least one light source adapted to transmit the lever signal in the form of light energy. Here, the transducer matrix includes light detection means adapted to register the emitted light energy, and based thereon, produce the data signal. Hence, a robust and cost efficient design is attained.

According to yet another embodiment of this aspect of the inven- tion, the energy emitter means instead includes at least one magnetic member, which is adapted to transmit the lever signal in the form of magnetic energy. In this case, the transducer matrix includes Hall-sensor means adapted to register the magnetic energy from the magnetic member, and based thereon, produce the data signal. Thereby, a robust design is accomplished, which is also relatively insensitive to dirt and wear.

According to still another embodiment of this aspect of the invention, the gearshift lever is pivotable around a support member in two dimensions. It is presumed that at least three gear positions are selectable and that these are distributed in a two- dimensional plane. The transducer matrix is further configured to detect gear-lever positions in two dimensions. Thus, the gearshift lever can be made convenient to manipulate, and the overall design becomes compact.

According to another embodiment of this aspect of the invention, the control device includes a sliding block with a guide contour through which a distal end of the gearshift lever extends towards the transducer matrix. The guide contour intersects a space of movement for the distal end and restricts the pivoting of the gearshift lever, such that the distal end is movable between the at least two gear positions exclusively along a predefined set of paths. Hence, a desired gearshift pattern can be implemented. Moreover, for cost efficiency, the transducer matrix configuration can be specifically adapted to the gearshift pattern.

According to another aspect of the invention, the object is achieved by a motor vehicle, which includes the above-proposed gear-control device.

According to still another aspect of the invention, the object is achieved by the method described initially, wherein at least one intermediate position of the gearshift lever is detected, where the at least one intermediate position is located on a path between at least one first and at least one second position of the gear positions. Information reflecting the at least one intermediate position is included in the data signal. In response to the data signal, at least one gearbox parameter is generated, which is adapted to control at least one characteristic of the gearbox other than a gear to be engaged. The advantages of this method, as well as the preferred embodiments thereof, are apparent from the discussion hereinabove with reference to the proposed vehicle arrangement.

According to a further aspect of the invention the object is achieved by a computer program loadable into the internal memory of a computer, comprising software for controlling the above proposed method when said program is run on a com- puter. According to another aspect of the invention the object is achieved by a computer program product, having a program recorded thereon, where the program is to make a computer control the above proposed method.

Further advantages, advantageous features and applications of the present invention will be apparent from the following description and the dependent claims.

BRIEF DESCRI PTION OF THE DRAWINGS

The present invention is now to be explained more closely by means of embodiments, which are disclosed as examples, and with reference to the attached drawings.

Figure 1 shows a schematic perspective view of a gearshift control device according to one embodiment of the invention, Figure 2 depicts a sliding block, which restricts the movements of the gearshift lever, such that a distal end thereof is movable between the gear positions exclusively along a predefined set of paths,

Figure 3 schematically shows a motor vehicle including the proposed gearshift control device, and

Figure 4 shows a flow diagram illustrating the general method according to the invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

We refer initially to Figure 1 , which shows a schematic perspec- tive view of a gearshift control device for changing gears of a gearbox in a motor vehicle according to one embodiment of the invention. The proposed control device includes a gearshift lever

100, a central unit 140 and a transducer matrix 120, which in turn, includes a plurality of sensors that each is adapted to con- tactlessly receive a non-electric signal and convert this signal into a data signal d of an electric format. The gearshift lever 100 is movable between at least two gear positions. Here, these positions are designated with A, B, C, D, E and F respectively. Each position A, B, C, D, E and F represents a particular gear of the gearbox to be controlled. For example, the position A, B, C, D and E may represent gears 1 through 5, while the position F may represent a reverse gear.

Preferably, the positions A, B, C, D, E and F correspond to the end locations of a guide contour in a sliding block as shown in Figure 2. However, this will be discussed in more detail below.

Returning now to Figure 1 , the gearshift lever 100 has a proximate end to which a handle 105 is fitted, and a distal end 1 12 including an energy emitter means 1 15. Hence, a user may manipulate the gearshift lever 100 by gripping the handle 105 push/ pull the handle 105 in a desired direction, and thereby cause the energy emitter means 1 15 to move over the transducer matrix 120. The energy emitter means 1 15 is adapted to emit a lever signal representative of the location of the gearshift lever 100. Specifically, the transducer matrix 120 is configured to detect where the gearshift lever 100 is located, i.e. whether the lever 100 is located at a particular gear position A, B, C, D, E or F, or if the lever 100 is located at an intermediate position between the gear positions A, B, C, D, E and F. Figure 2 exemplifies three such intermediate positions 210, 220 and 230 respectively on a path P between a first gear position B and a second gear position C. According to one embodiment of the invention, a set of possible paths P between the gear positions A, B, C, D, E and F is defined by a guide contour 235 of a sliding block 130. In any case, information reflecting the gearshift lever's 100 position being detected by the transducer matrix 120 is included in the data signal d irrespective of whether or not the lever 100 is located at a particular gear position A, B, C, D, E or F, or if the lever 100 is located at an intermediate position, such as 210, 220 or 230.

The central unit 140 is adapted to receive the data signal d, and in response thereto, generate a control signal S_gear and/or at least one gearbox parameter P_gear depending on the registered gearshift lever position. The control signal S_gear is adapted to control a gearbox, such that the gearbox engages a gear being represented by a gear position where the gearshift lever 100 currently is located, for example a second gear is equivalent to the position B as illustrated in Figure 2. If however, the gearshift lever 100 is located at an intermediate position, e.g. as illustrated in Figure 1 or the position 220 in Figure 2, the gearbox is controlled not to engage any gear. Instead, the central unit 140 here generates at least one gearbox parameter P_gear, which is adapted to control at least one characteristic of the gearbox other than a gear to be engaged.

For example, a first gearbox parameter P_gear may be adapted to cause a freewheel-clutch operation, i.e. a gear release without immediate engagement of a new gear. Thus, when the gearbox is set to a freewheel mode, the vehicle rolls without any propelling or retarding influence from the engine. The intermediate position 210 constitutes an example of an appropriate position at which the freewheel mode can be entered, and the intermediate position 210 represents another example of when the gearbox preferably is set in the freewheel mode.

A second gearbox parameter P_gear may be adapted to cause a gear-synchronization in respect of an estimated future gear to be engaged. For instance, if a gearshift lever path P is registered by the transducer matrix 120 where it is found that gearshift lever 100 moves from the intermediate position 220 to the intermediate 230, it can be expected that the driver intends to engage a gear being associated with the gear position C, for example a third gear. Therefore, second gearbox parameter P_gear causes a gear-synchronization to the third gear already at this point in time.

It is further advantageous if the central unit 140 includes, or is associated with, a computer readable medium 145, which has a program recorded thereon; where the program is adapted to make the central unit 140 control the above-described procedu- re. According to one embodiment of the invention, the energy emitter means 1 15 includes at least one light source (e.g. in the form of a respective laser or a LED (light emitting diode)), which is adapted to transmit the lever signal in the form of light energy. In this case, the transducer matrix 120 includes light detection means, e.g. a LAPS (light-addressable potentiometric sensor), photodiodes or LDRs (light dependent resistors), which are/is adapted to register the light energy emitted from the light source, and based thereon produce the data signal d.

According to another embodiment of the invention, the energy emitter means 1 15 includes at least one magnetic member, which is adapted to transmit the lever signal in the form of magnetic energy. Here, the transducer matrix 120 includes Hall- sensor means, i.e. a set of transducers, which each varies its output voltage in response to any changes in a registered magnetic field density. Hence, the transducer matrix 120 is adapted to register the magnetic energy from the emitter means 1 15, and based thereon produce the data signal d.

Irrespective of the sensor technology used, the gearshift lever 100 is preferably pivotable around a support member in at least one dimension. According to one embodiment of the invention, the gearshift lever 100 is pivotable around a first axis R1 and a second axis R2 of a support member 1 10 in two dimensions D1 and D2 respectively. For clarity reasons, in Figure 1 the support member 1 10 is only represented symbolically without any structural elements for fixating the member 1 10 as such. This embodiment also presumes that at least three gear positions are selectable, e.g. the six positions A, B, C, D, E and F illustrated in Figures 1 and 2, and that these positions are distributed in a two-di- mensional plane (for instance according to a general H-pattern). Furthermore, the transducer matrix 120 is configured to detect gear-lever positions in two dimensions.

As mentioned above, the gearshift control device may include a sliding block 130, which restricts the movements of the gearshift lever 100 to a set of predefined paths P between the gear positions A, B, C, D, E and F. Figure 2 depicts one example of such a sliding block 130. According to one embodiment of the invention, a distal end 1 12 of the gearshift lever 100 extends through the guide contour 235 towards the transducer matrix 120. As illustrated in Figure 1 , the guide contour 235 intersects a space of movement for the distal end 1 12 and restricts the gearshift lever 100, so that it can only be pivoted around the support member 1 10 in such a manner that the distal end 1 12 moves between the at least two gear positions A, B, C, D, E and F along a set of paths P defined by a guide contour 235.

Figure 3 schematically shows a motor vehicle 300 that includes the proposed gearshift control device. Here, manipulations of a gearshift lever 100 causes the control device to generate a control signal S_gear and at least one gearbox parameter P_gear respectively. A gearbox 310 receives the control signal S_gear and the at least one gearbox parameter P_gear, and in response thereto, controls the operation of a transmission 320 to at least one pair of drive wheels 330 of the vehicle 300.

In order to sum up, the general method of controlling a gear box of a motor vehicle according to the invention will now be descri- bed with reference to the flow diagram in Figure 4.

A first step 410, receives a lever signal representative of the location of a gearshift lever. Subsequently, a step 420 contactless- Iy detects the lever signal, and in response thereto, produces a data signal d. Thereafter, a step 430 investigates whether or not the data signal d indicates that the lever is located at a gear position. If step 430 finds that the lever is located at gear position, a step 440 follows. Otherwise, the procedure continues to a step 450.

Step 440 generates a control signal S_gear, which is adapted to control the gearbox in response to the registered location of the gearshift lever relative to at least two selectable gear positions, such that the gearbox engages a gear being represented by a gear position where the gearshift lever currently is located. In other words the control signal S_gear causes the gear detected in step 430 to be engaged. Thereafter, the procedure loops back to step 410.

Step 450 investigates whether or not at least one parameter criterion is fulfilled, i.e. a condition for generating the proposed gearbox parameter P_gear- If no such criterion is found to be ful- filled, the procedure loops directly back to step 410. Namely, all intermediate positions between the gear positions need not be associated with any gearbox parameter P_gear- If, however, at least one parameter criterion is fulfilled, a step 460 follows.

Step 460 generates at least one gearbox parameter P_gear, which is adapted to control at least one characteristic of the gearbox other than a gear to be engaged, for example a freewheel-clutch operation, and/or a gear-synchronization in respect of an estimated future gear to be engaged. Subsequently, the procedure loops back to step 410.

All of the process steps, as well as any sub-sequence of steps, described with reference to Figure 4 above may be controlled by means of a programmed computer apparatus. Moreover, although the embodiments of the invention described above with reference to the drawings comprise computer apparatus and processes per- formed in computer apparatus, the invention thus also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice. The program may be in the form of source code; object code, a code intermediate source and object code such as in partially compiled form, or in any other form suitable for use in the implementation of the process according to the invention. The carrier may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a Flash memory, a ROM (Read Only Memory), for example a CD (Compact Disc) or a semiconductor ROM, an EPROM (Erasable Programmable Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or a magnetic recording medium, for example a floppy disc or hard disc. Further, the carrier may be a transmissible carrier such as an electrical or optical signal which may be conveyed via electrical or optical cable or by radio or by other means. When the program is embodied in a signal which may be conveyed directly by a cable or other device or means, the carrier may be constituted by such cable or device or means. Alternatively, the carrier may be an integrated circuit in which the program is embedded, the integrated circuit being adapted for performing, or for use in the performance of, the relevant processes.

The invention is not restricted to the described embodiments in the figures, but may be varied freely within the scope of the claims.

Claims

1 . A gearshift control device for changing gears of a gearbox (310) in a motor vehicle (300), the control device comprising: a gearshift lever (100) being movable between at least two gear positions (A, B, C, D, E, F) which each represents a particular gear of the gearbox (310), a central unit (140) adapted to generate a control signal (S_gear) to the gearbox (310) in response to a location of the gearshift lever (100) relative to the at least two selectable gear positions (A, B, C, D, E, F), such that the gearbox (310) engages a gear being represented by a gear position (B) where the gearshift lever (100) currently is located, an energy emitter means (1 15) adapted to emit a lever signal representative of the location of the gearshift lever (100), and a plurality of sensors (120) adapted to contactlessly detect the lever signal, and in response thereto, produce a data signal (d), characterized i n that the plurality of sensors include a transducer matrix (120) configured to: detect at least one intermediate position (210, 220, 230) of the gearshift lever (100), the at least one intermediate position

(210, 220, 230) being located on a path (P) between at least one first and at least one second position of the gear positions (A, B,

C, D, E, F), and include information reflecting the at least one intermediate position (210, 220, 230) in the data signal (d), and the central unit (140) is adapted to receive the data signal (d), and in response thereto, generate at least one gearbox parameter (P_gear) adapted to control at least one characteristic of the gearbox (310) other than a gear to be engaged.

2. The device according to claim 1 , characterized i n that the at least one gearbox parameter (P_gear) is adapted to cause at least one of: a freewheel-clutch operation, and a gear-synchronization in respect of an estimated future gear (C) to be engaged.

3. The device according to any one of the preceding claims, characterized in that the energy emitter means (1 15) comprises at least one light source adapted to transmit the lever signal in the form of light energy, and the transducer matrix (120) comprises light detection means adapted to register said light energy, and based thereon, produce the data signal (d).

4. The device according to any one of the claims 1 or 2, cha- racterized i n that the energy emitter means (1 15) comprises at least one magnetic member adapted to transmit the lever signal in the form of magnetic energy, and the transducer matrix (120) comprises Hall-sensor means adapted to register said magnetic energy, and based thereon, produce the data signal (d).

5. The device according to any one of the preceding claims, characterized i n that the gearshift lever (100) is pivotable around a support member (1 10) in two dimensions (D1 , D2), at least three gear positions (A, B, C, D, E, F) are selectable which are distributed in a two-dimensional plane, and the transducer matrix (120) is configured to detect gear-lever positions in two dimensions.

6. The device according to claim 5, characterized i n that it comprises a sliding block (130) with a guide contour (235) through which a distal end (1 12) of the gearshift lever (100) extends towards the transducer matrix (120), the guide contour (235) intersecting a space of movement for the distal end (1 12) and restricting the gearshift lever (100) to be pivoted around the support member (1 10) such that the distal end (1 12) is movable between the at least two gear positions (A, B, C, D, E, F) exclusively along a predefined set of paths (P).

7. A motor vehicle (300) comprising a gearbox (310) and a gearshift control device according to any one of the preceding claims.

8. A method of controlling gear changes in a gearbox (310) of a motor vehicle (300), the method comprising: registering a location of a gearshift lever (100), the lever (100) being movable between at least two gear positions (A, B, C, D, E, F) which each represents a particular gear of the gearbox (310), generating a control signal (S_gear) to the gearbox (310) in response to a registered location of the gearshift lever (100) relative to the at least two selectable gear positions (A, B, C, D, E, F), such that the gearbox (310) engages a gear being represented by a gear position (B) where the gearshift lever (100) cur- rently is located, emitting a lever signal representative of the location of the gearshift lever (100), detecting contactlessly the lever signal, and producing, in response thereto, a data signal (d), characterized by detecting at least one intermediate position (210, 220, 230) of the gearshift lever (100), the at least one intermediate position

(210, 220, 230) being located on a path (P) between at least one first and at least one second position of the gear positions (A, B, C, D, E, F), including information reflecting the at least one intermediate position (210, 220, 230) in the data signal (d), receiving the data signal (d), and in response thereto, generating at least one gearbox parameter (P_gear) adapted to control at least one characteristic of the gearbox (310) other than a gear to be engaged.

9 The method according to claim 8, characterized by the at least one gearbox parameter (P_gear) being adapted to cause at least one of: a freewheel-clutch operation, and a gear-synchronization in respect of an estimated future gear (C) to be engaged.

10. The method according to any one of the claims 8 or 9, characterized by transmitting the lever signal in the form of light energy, registering said light energy, and based thereon, producing the data signal (d).

1 1 . The method according to any one of the claims 8 or 9, characterized by transmitting the lever signal in the form of magnetic energy, registering said magnetic energy, and based thereon, producing the data signal (d).

12. A computer program loadable into the internal memory of a computer, comprising software for controlling the steps of any of the claims 8 to 1 1 when said program is run on the computer.

13. A computer program product (145), having a program recorded thereon, where the program is to make a computer control the steps of any of the claims 8 to 1 1 .