GEAR SELECTOR DEVICE FOR A VEHICLE GEARBOX

Abstract: A gear selector device (1) for an indirectly manoeuvred vehicle gearbox has a pivotably mounted manoeuvring column (3) and a locking arrangement (17) for locking the manoeuvring column in predetermined positions. The locking arrangement includes a first locking part (18) arranged on the manoeuvring column and a second locking part (19) which cooperates with the first part and forms a cover for the housing (4) of the gear selector device and has a guide slot (21) for the manoeuvring column. A spring-loaded first locking body (31) on the manoeuvring column (3) can be brought into engagement with different locking members (30) in the cover and thereby hold the manoeuvring column in different positions.

Description: GEAR SELECTOR DEVICE FOR A VEHICLE GEARBOX The present invention relates to a gear selector device for a gearbox intended for motor vehicles and of the type which is manoeuvred indirectly via a control unit connected to the gear selector device, provided with a pivotably mounted manoeuvring column, and with a locking arrangement for locking the manoeuvring column in predetermined positions. In automotive technology it is becoming more and more common, especially in the case of heavy vehicles such as, for example, lorries and buses, to attempt to make the driver's work easier by reducing and simplifying the effort required for changing gear. This is achieved by means of indirect manoeuvring of the gearbox, the driver manoeuvring a gear selector device so as to cause the latter to emit, as a function of the position, different signals intended to carry out via the servo the actual manoeuvring of the gearbox, i.e. to effect engagement and disengagement of gears. By having a control unit detect the actual driving conditions, such as, for example, speed, acceleration, engaged gear and engine speed, it is possible to further facilitate the work of the driver. The control unit can then calculate which gear should be engaged and can present its suggestion to the driver on a gear indicator. Then, with the aid of the gear selector device, the driver can change gear according to the suggestion or deviate from the suggestion. The gear selector device may also permit a choice between, for example, different semiautomatic or fully automatic predetermined gear programs. In order to permit simple adjustment of the gear selector device to desired positions, it is known to use a single manoeuvring column and to mount the latter pivotably in different planes, for example in a plane parallel to the longitudinal direction of the vehicle and in planes transverse to this plane. In one embodiment according to US-A-4,519,266, the locking arrangement which holds the manoeuvring column in different positions is located in connection with the centre of pivoting of the manoeuvring column and permits a gear-changing pattern of the type which is customary in manual gearboxes. There are no non-locking positions. In another design, according to SE-A-S803674-4, the manoeuvring column can be adjusted to different positions in a first plane and can be pivoted non- lockingly from these positions transverse to this plane. The locking arrangement which holds the manoeuvring column in different longitudinal positions is in this case designed with a cam curve in the bottom of the housing of the gear selector device, but there is however no possibility of locking the manoeuvring column in the lateral direction. Among the disadvantages associated with these known embodiments is the fact that, when a modified gear-changing pattern is required, it is necessary to alter the housing of the gear selector device internally in order to obtain new positions for the manoeuvring column. In addition, the locking arrangement competes for the space for the sensors which are required for detecting the different positions of the manoeuvring column. The aim of the invention is to provide a gear selector device which is of simple construction and can be easily modified in order to satisfy different requirements in respect of gear-changing patterns, but which is nevertheless easy and convenient for the driver to operate. According to the invention, this aim is achieved by virtue of the fact that the locking arrangement includes a first locking part arranged on the manoeuvring column, and a second locking part which cooperates with the first locking part and is connected to the housing in which the manoeuvring column is mounted, and which has a guide slot which is intended for the manoeuvring column and in which there are locking members which define the predetermined positions for the manoeuvring column in the guide slot. In this case the second locking part advantageously forms a cover for the housing and is detachably mounted on the latter. According to a particularly advantageous embodiment, the locking members consist of recesses which are arranged in the second locking part and which cooperate with a first locking body, spring-loaded in the direction of the recesses, in the first locking part, and the first locking body is displaceable along the manoeuvring column and has a suitable form for centring in the recesses. With a gear selector device according to the invention, great adaptability to different requirements is obtained, since one and the same housing for the gear selector device can be combined with differently shaped covers, incorporated in the second locking part. This results in a simple adaptation to different types of gearboxes and permits a large number of different gear-changing patterns. The invention is described in greater detail below on the basis of exemplary embodiments shown in the drawing, in which : Fig. 1 shows a diagrammatic end view, partially in cross-section, of a gear selector device according to the invention, Fig. 2 shows a diagrammatic side view, partially in cross-section, of the gear selector device in Fig. 1, Fig. 3 shows, from above, how the guide groove is designed in the embodiment according to Figs. 1 and 2, Fig.4 indicates the different gear positions which can be obtained in Fig. 3, Fig. 5 shows a variant of the embodiment in Fig. 2, Figs. 6 and 7 are based on Fig. 5 and correspond to Figs. 3 and 4, Fig. 8 shows another variant of the embodiment in Fig. 2, Figs. 9 and 10 are based on Fig. 8 and correspond to Figs. 3 and 4, Fig. 11 shows a detail of the manoeuvring column, and Fig. 12 shows a view, from below, of a section of the second locking part in the embodiment according to Figs. 1-3. A gear selector device 1 according to the invention is designed to be connected in known manner via lines 2 to a control unit (not shown) which is intended for a motor vehicle gearbox and which, via the servo on the gearbox, effects engagement and disengagement of gears as a function of the position of a manoeuvring column 3 in the gear selector device 1 , which column is manoeuvred by the driver. Since the invention relates solely to the gear selector device, only the latter is shown. The control unit can be provided in a known manner, by means of different sensors, with information relating to the actual driving conditions and can, on the basis of this, calculate which gear should be used. The driver can in this way obtain information, for example via a gear indicator, on which gear is being used at a given time and on which gear the control unit recommends. This gives the driver the possibility of choosing, as and when required, the gear or gear-changing pattern. He can choose, for example, between automatic and manual transmission in different forms. The manoeuvring column 3 is mounted in a housing 4 which is intended to be fixed securely in the vehicle, and the column is mounted in a cradle 5 which is borne pivotably in the housing 4. In this way, the manoeuvring column 3 together with the cradle 5 can be pivoted about a horizontal axis line 6 (Fig. 1), in the direction of arrows 7 or 8 (Fig.2). In the cradle 5, the manoeuvring column 3 is mounted pivotably about a horizontal axis line 9, in the direction of arrows 10 or 11. The axis line 9 is at right angles to the axis line 6 and intersects the latter at a pivoting centre 12 and is preferably oriented in the longitudinal direction of the vehicle. However, it is also possible for the axis lines 6 and 9 to be situated at different levels and, therefore, for the bearing of the manoeuvring column to be designed differently. The manoeuvring column 3 cooperates with a number of different sensors 13 for indicating different positions of the manoeuvring column. These sensors can be designed in a number of different ways and can consist for example, as shown, of circuit breakers which cooperate with suitably designed cam curves 14. For indicating the pivoting in the direction of arrows 7 or 8, for example, the circuit breakers can be mounted in the cradle 5 while the cam curves 14 are secured in the housing 4, or vice versa. For indicating the pivoting in the direction of arrows 10 or 11, the cradle 5 can support one or more sensors 15, for example circuit breakers, which cooperate with cam curves 16 on the manoeuvring column 3, or vice versa. It is also well known to use, for example, contactless sensors or other types of sensors. These sensors are connected via the lines 2 to the control unit (not shown). Arranged between the free end of the manoeuvring column and the pivoting centre 12 is a locking arrangement 17 by means of which the manoeuvring column 3 can be locked in predetermined positions, depending on which movement pattern has been chosen for the manoeuvring column. This locking arrangement 17 includes a first locking part 18 arranged on the manoeuvring column 3, and a second locking part 19 which is incorporated in the gear selector device housing 4 and is designed to cooperate with the first locking part 18. The second locking part 19 can advantageously form a cover for the housing 4 and is expediently protected by a gaiter 20 which is attached to the manoeuvring column 3 and to the housing 4. In the second locking part 19 there is a guide slot 21 intended for the manoeuvring column 3 and defining the movement pattern of the manoeuvring column. This guide slot 21 is normally made up of a longer slot 22, which permits manoeuvring in the direction of arrows 7 and 8, and of a number of transverse, shorter slots 23-25, which permit manoeuvring in the direction of arrows 10 and 11. In the embodiment according to Figs. 1-3, the manoeuvring column 3 can be pivoted between four fixed positions in the slot 22, namely a first position 22a at the level of the slot 23, a second position 22b between the slots 23 and 24, a third position 22c at the level of the slot 24, and a fourth position 22d at the level of the slot 25. In addition, it is possible to pivot the manoeuvring column 3 from the fourth position 22d in the direction of arrow 8 to a non- locking position 22d' where the manoeuvring column remains only for as long as it is held there. From the position 22c at the level of the slot 24, the manoeuvring column can be pivoted either in the direction of arrow 10 to a fixed position 24a, or in the direction of arrow 11 to a fixed position 24b. From both position 22a at slot 23 and position 22d at slot 25, the manoeuvring column 3 can be moved in the direction of arrow 10 or 11 to non-locking side positions atthe respective slot ends. The meaning of the different positions of the manoeuvring column 3 in Figs. 1-3 emerges more clearly from Fig.4, which shows diagrammatically the movement pattern according to Fig. 3. Position R corresponds to position 22a and represents reverse position. By means of a sideways movement in the slot 23, a higher or lower reverse gear can be obtained, + and - indicating a change to a higher or lower gear, respectively, than that chosen by the automatic mechanism. The position N corresponds to position 22b and represents neutral position. The position AUTO corresponds to positron 22c and represents automatic transmission. In position HOLD, corresponding to 24a, the engaged gear is held, while in position EBR, corresponding to 24b, the engine brake is coupled. In position REC, corresponding to 22d, the system recommends a specific gear, + and - indicating a change of recommended gear to a higher or lower gear, respectively, than that which is recommended. In the position SHIFT, corresponding to 22d', disengagement is carried out and the gear is changed on the basis of selection in the REC position. This embodiment according to Figs. 1-4 represents a fully automatic version in which the control device in the "automatic positions" chooses the gear and carries out gear-changing automatically. Figs. 5-7 show instead a semiautomatic embodiment in which the control device selects the gear, but where the driver manoeuvres the clutch and thereby triggers the gear change. In the guide slot 21 there is, as previously, a longer slot 22, but the number of transverse slots 23-26 is now four instead of three. There are five fixed positions in the slot 22, namely 22a-e. Only non¬ locking positions can be obtained in one direction in the transverse slots 23- 26. As emerges more clearly from igs. 6 and 7, the positions 22a-e correspond to R, N, 1, 2 and 3, respectively, where R and N represent, as previously, the reverse position and neutral position, respectively. The positions 1, 2 and 3 represent different gear range positions. As previously, + and - indicate a change of recommended gear to a higher or lower gear, respectively. Figs. 8-10 also show a semiautomatic embodiment, similar to that in Figs.5-7. The transverse slots are here reduced to three, namely 23-25. There are still five fixed positions in the slot 22, namely 22a-e. From the slot 22, only non¬ locking positions can be obtained in one direction in the slots 23-25. According to Figs. 9 and 10, the positions 22a-e here correspond to R, N, A, M and N, respectively, where R and N still represent the reverse position and neutral position, respectively. The positions A and M, corresponding to 22c and 22d, represent the automatic position and manual position, respectively. The position N corresponding to 22e represents an extra neutral position intended to be used in particular circumstances, for example in emergency situations, when decoupling of the whole gear selector device is desired. The symbols + and - have the same meanings as before. The design of the locking arrangement 17 emerges more clearly from Figs. 8, 11 and 12, where Fig. 11 shows in principle the same feature as in Fig. 8, but in simplified form. As has already been mentioned, the locking arrangement 17 is divided up into a first locking part 18 arranged on the manoeuvring column 3 and a second locking part 19 cooperating with the first locking part and joined to the housing 4. In the guide slot 21 there are arranged on the underside of the second locking part 19 a number of locking members 30, here in the form of rounded recesses. These locking members 30 can cooperate one at a time with a first locking body 31 incorporated in the first locking part 18 and mounted displaceably on the manoeuvring column 3. With the aid of a spring 32, which bears against an attachment 33 arranged securely on the manoeuvring column 3, the first locking body 31 is loaded in the direction of the free end of the manoeuvring column. By means of cooperation with suitable locking members 30, the first locking body 31 can in this way fix the manoeuvring column in the desired position. The rounded shape means that the first locking body 31 can be pivoted, counter to a certain force from the spring 32, between different fixed positions, i.e. can be brought into engagement with different locking members. At the same time, springing back to a centred position is possible by pivoting the manoeuvring column slightly past a centring locking member. From, for example, the centred position 22d in Fig. 12, the manoeuvring column, when pivoted in either one direction in slot 25 or downwards in slot 22, can be made to spring back to the centred position 22d. The manoeuvring column 3 also supports a second locking body 34 incorporated in the first locking part 18 and situated so that the first and the second locking body 31 and 34, respectively, are located on each side of the second locking part 19. This second locking body 34 is secured on the manoeuvring column 3 and is situated near or can slide along the second locking part 19 and its task is to cooperate with at least one locking device 35 on the second locking part 19 so as to prevent the manoeuvring column 3 from being pivoted inadvertently to a particular setting. The locking device 35 can consist, for example, of a raised section around the transverse slot 23 for the reverse position R. A stop surface 36 on the locking device 35 is intended to catch the second locking body 34. If required, however, the second locking body 34 can be made to pass the locking device 35 in order to be able to engage reverse position, for example. This is possible by virtue of the fact that the manoeuvring column 3 is mounted axially movable and can be lifted in the direction of arrow 37, counter to the force from the spring 32, at the same time as it is pivoted in the direction of arrow 7. Upon pivoting back in the direction of arrow 8, the manoeuvring column returns to its axially inner position under the effect of the spring 32. The second locking body 34 can in this respect limit the return in the axial direction, but it is also possible, for example, to let the manoeuvring column touch the bottom of a moderately deep hole 38 in a bracket 39 for the manoeuvring column. Instead of arranging the locking members 30, as shown here, on the inside of the second locking part 19 facing away from the free end of the manoeuvring column, the locking members 30 can be arranged on the outside of the second locking part 19, with correspondingly different positioning of the first and the second locking bodies 31 and 34, respectively. In this case it is necessary to displace the manoeuvring column in the opposite direction to that previously stated in order to be able to pass the locking device 35. The recesses 30 and the first locking body 31 have been shown here with a rounded shape, but it is also possible to use other shapes which permit good locking in fixed positions and yet allow movement between fixed positions and permit springing-back in certain positions.

Claims: Patent claims 1. Gear selector device for a gearbox intended for motor vehicles and of the type which is manoeuvred indirectly via a control unit connected to the gear selector device (1), provided with a pivotably mounted manoeuvring column (3), and with a locking arrangement (17) for locking the manoeuvring column in predetermined positions, characterised in that the locking arrangement (17) includes a first locking part (18) arranged on the manoeuvring column (3), and a second locking part (19) which cooperates with the first locking part and is connected to the housing (4) in which the manoeuvring column is mounted, and which has a guide slot (23) which is intended for the manoeuvring column (3) and in which there are locking members (30) which define the predetermined positions for the manoeuvring column in the guide slot. 2. Gear selector device according to Claim 1, characterised in that the second locking part (19) forms a cover for the housing (4) and is detachably mounted on the latter. 3. Gear selector device according to Claim 1 or 2, characterised in that the locking members (30) consist of recesses which are arranged in the second locking part (19) and which cooperate with a first locking body (31), spring-loaded in the direction of the recesses, in the first locking part (18). 4. Gear selector device according to Claim 3, characterised in that the first locking body (31) is displaceable along the manoeuvring column (3) and has a suitable form for centring in the recesses. 5. Gear selector device according to Claim 3 or 4, characterised in that the recesses (30) are arranged in the side of the second locking part (19) facing away from the free end of the manoeuvring column (3). 6. Gear selector device according to any of Claims 3-5, characterised in that the first locking part (18) also includes a second locking body (34) which, in relation to the first locking body (31), is arranged on the opposite side of the second locking part (19) and is designed, together with at least one locking device (35) on the latter, to prevent inadvertent pivoting of the manoeuvring column (3) to at least one predetermined position. 7. Gear selector device according to Claim 6, characterised in that the locking device (35) consists of a raised portion at the said predetermined position, and in that the manoeuvring column (3) together with the second locking body (34) is axially displaceable to a level where the second locking body (34) can pass the locking device (35). 8. Gear selector device according to any of Claims 1-7, characterised in that the guide slot (21) is formed of a first long slot (22) which is preferably designed to be oriented with its longitudinal direction in the longitudinal direction of the vehicle, and at least one second, shorter slot (23-26) which is directed transverse to the first slot (22). 9. Gear selector device according to Claim 8, characterised in that in the guide slot (21) there are a number of fixed positions (22a-d, 24a, 24b) for the manoeuvring column (3), at least along the first slot (22). 10. Gear selector device according to Claim 9, characterised in that, in at least one of the fixed positions (22d), the manoeuvring column (3) can be pivoted away to a non-locking position (22d') in at least one direction.

Inventors: SKEPPSTROEM TOMAS, SKEPPSTROEM, TOMAS
Applicants: SAAB SCANIA AB, SAAB-SCANIA AKTIEBOLAG
Application year: 1990
Main classification: B60K20
IPC codes: F16H59, F16H61