GB2089451A

GB2089451A - Positive location device

Info

Publication number: GB2089451A
Application number: GB8132170A
Authority: GB
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 1980-12-13
Filing date: 1981-10-26
Publication date: 1982-06-23
Also published as: CA1184791A; SE454117B; GB2089451B; DE3047117C2; DE3047117A1; SE8107329L

Abstract

To provide positive location of switch positions in switching equipment, e.g. gear shifting mechanism, having a control member (2) movable through more than one line of movement (i.e. rotation and axial translation), a spring loaded rolling contact body 9 co-operates with a member having contoured surface. The contoured surface includes a channel 8 bounded by ridges 6, 7 for positive location in the axial translation direction and recesses 16, 17, 19, 20 for positive location in the rotational direction. <IMAGE>

Description

SPECIFICATION Positive location device The invention relates to a device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement. Such switching equipment may include, for example, a central shaft or a gearshift lever of a gear-change transmission. The device provided by the invention may also be useful in other switching, equipment such as electrical switches and hydraulic or pneumatic valves where the switching means have several lines of movement. The invention is described herein under with reference to its use in a gear-change transmission, but this is by way of example only.

It is necessary to provide positive location means on a central shaft or a gearshift lever of a gear-change transmission not only in the line of the selection movement, but also in the line of the gear-changing movement. Already known positive location devices provide a means for stopping only in one line of movement, so that it would really be necessary to have two such devices on a central shaft or a gearshift lever of a gear-change transmission. The friction force to be absorbed by the gearshift lever would correspond to the sum of the friction forces occurring in both such devices and would therefore be considerable.

The invention provides a device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement, the device comprising a spring loaded rolling contact body and a member co-operable therewith and having a contoured surface including a channel for positive location of the rolling contact body in one line of movement of the control member and lands for positive location of the rolling contact body in another line of movement of the control member.

Compared with the prior art, the invention has the advantage that only one positive location device is necessary for ensuring stopping along the two lines of movement of a gear-change transmission, one for gear selection and the other for gear change. In this way good efficiency (lower frictional forces) can be achieved and the component requirement can be kept to a minimum. Due to the small number of components there is less wear, and the manufacturing cost can be reduced. The stopping device can be used on all gear-change transmissions and is suited in particular for small transmissions, because it requires only a small amount of space.

The invention is illustrated by the drawings of which: Figure 1 is a perspective view of a part of a positive location device according to the invention; Figure 2 is a sectional view of a positive location device according to the invention, including the part thereof shown in Figure 1; and Figure 3 is a sectional view taken about the line Ill-Ill in Figure 2.

With reference to Figure 1 of the drawings, a member 1 and a striker 3 are mounted on a central shaft 2. The central shaft 2 runs in bearings 4 and 5 and is both rotatable and axially movable. The striker 3 is provided for the operation of a guide bar for bringing in the various gears in a gear-change transmission.

The member 1 has a contoured surface in which a channel 8 is separated from surfaces 10 and 11 by ridges 6 and 7. The ridges 6 and 7 and the channel 8 form a positive location contour extending transversely to the axial direction of the central shaft 2 and providing the stops for the gear-change operation. In relation to the surfaces 10 and 1 1, the ridges 6 and 7 are of uniform height over their entire length. The ridges 6 and 7 follow the contour of the surfaces 10 and 11 which form the positive location contour for selection.

The contour of surface 10 (Figure 1) includes lands 1 6 and 17, indented with respect to adjacent portions. Such a raised section such as at 1 8, of the surface 10. The contour of surface 11 also comprises indented lands 1 9 and 20, with elevations, such as 21, adjacent to them. The contours of the surfaces 10 and 11 are identical or at least similar to each other. In Figure 2 the contour for selection is revealed. Balls 13 provide a particularly low-friction bearing support for a rolling contact ball 9. A bearing part 12 is pressed against the balls 1 3 by means of a pressure spring 14 and thus against the rolling contact ball 9, whereby the latter is kept in engagement with stopping contour.

Instead of using balls 13, the rolling contact ball 9 may be supported directly by the bearing part 12, preferably made from synthetic material (not shown on the drawing).

Figure 3 shows the stopping contour for the gear-change operation The stopping contour for selection (Figures 1 and 2) may be shaped such as to provide the driver with a feel of the forces necessary so that he receives information via the selected line on the force to be applied during selection, The stopping contour for the gear-change operation (Figures 1 and 3) may be shaped such that the ball 9, whilst rolling off the downward sloping flanks 22 and 23 of the ridges 6 and 7, assists on the gear-change operation.

1. A device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement, the device comprising a spring loaded rolling contact body and a member Co- operable therewith and having a contoured surface including a channel for positive location of the rolling contact body in one line of movement of the control member and lands for positive location of the rolling contact body in another line of movement of the control member.

2. A device according to claim 1 in which the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Positive location device The invention relates to a device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement. Such switching equipment may include, for example, a central shaft or a gearshift lever of a gear-change transmission. The device provided by the invention may also be useful in other switching, equipment such as electrical switches and hydraulic or pneumatic valves where the switching means have several lines of movement. The invention is described herein under with reference to its use in a gear-change transmission, but this is by way of example only. It is necessary to provide positive location means on a central shaft or a gearshift lever of a gear-change transmission not only in the line of the selection movement, but also in the line of the gear-changing movement. Already known positive location devices provide a means for stopping only in one line of movement, so that it would really be necessary to have two such devices on a central shaft or a gearshift lever of a gear-change transmission. The friction force to be absorbed by the gearshift lever would correspond to the sum of the friction forces occurring in both such devices and would therefore be considerable. The invention provides a device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement, the device comprising a spring loaded rolling contact body and a member co-operable therewith and having a contoured surface including a channel for positive location of the rolling contact body in one line of movement of the control member and lands for positive location of the rolling contact body in another line of movement of the control member. Compared with the prior art, the invention has the advantage that only one positive location device is necessary for ensuring stopping along the two lines of movement of a gear-change transmission, one for gear selection and the other for gear change. In this way good efficiency (lower frictional forces) can be achieved and the component requirement can be kept to a minimum. Due to the small number of components there is less wear, and the manufacturing cost can be reduced. The stopping device can be used on all gear-change transmissions and is suited in particular for small transmissions, because it requires only a small amount of space. The invention is illustrated by the drawings of which: Figure 1 is a perspective view of a part of a positive location device according to the invention; Figure 2 is a sectional view of a positive location device according to the invention, including the part thereof shown in Figure 1; and Figure 3 is a sectional view taken about the line Ill-Ill in Figure 2. With reference to Figure 1 of the drawings, a member 1 and a striker 3 are mounted on a central shaft 2. The central shaft 2 runs in bearings 4 and 5 and is both rotatable and axially movable. The striker 3 is provided for the operation of a guide bar for bringing in the various gears in a gear-change transmission. The member 1 has a contoured surface in which a channel 8 is separated from surfaces 10 and 11 by ridges 6 and 7. The ridges 6 and 7 and the channel 8 form a positive location contour extending transversely to the axial direction of the central shaft 2 and providing the stops for the gear-change operation. In relation to the surfaces 10 and 1 1, the ridges 6 and 7 are of uniform height over their entire length. The ridges 6 and 7 follow the contour of the surfaces 10 and 11 which form the positive location contour for selection. The contour of surface 10 (Figure 1) includes lands 1 6 and 17, indented with respect to adjacent portions. Such a raised section such as at 1 8, of the surface 10. The contour of surface 11 also comprises indented lands 1 9 and 20, with elevations, such as 21, adjacent to them. The contours of the surfaces 10 and 11 are identical or at least similar to each other. In Figure 2 the contour for selection is revealed. Balls 13 provide a particularly low-friction bearing support for a rolling contact ball 9. A bearing part 12 is pressed against the balls 1 3 by means of a pressure spring 14 and thus against the rolling contact ball 9, whereby the latter is kept in engagement with stopping contour. Instead of using balls 13, the rolling contact ball 9 may be supported directly by the bearing part 12, preferably made from synthetic material (not shown on the drawing). Figure 3 shows the stopping contour for the gear-change operation The stopping contour for selection (Figures 1 and 2) may be shaped such as to provide the driver with a feel of the forces necessary so that he receives information via the selected line on the force to be applied during selection, The stopping contour for the gear-change operation (Figures 1 and 3) may be shaped such that the ball 9, whilst rolling off the downward sloping flanks 22 and 23 of the ridges 6 and 7, assists on the gear-change operation. CLAIMS

2. A device according to claim 1 in which the channel is defined by a pair of ridges.

3. According to claim 1 or claim 2 in which the contoured surface member is integral with a stopping body fastened to the central shaft of a gear-change transmission.

4. A device according to any preceding claim in which the rolling contact body is mounted on antifriction bearings.

5. A device for providing positive location of switch positions in switching equipment having a control member movable through more than one line of movement, the device being substantially as described herein with reference to the drawings.