GB2048362A

GB2048362A - Mechanism for converting rotary into reciprocating motion

Info

Publication number: GB2048362A
Application number: GB8007266A
Authority: GB
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1979-03-28
Filing date: 1980-03-04
Publication date: 1980-12-10
Also published as: JPS55129575A; IT8020820A0; DE2912141A1; SE8002385L; FR2452641A1

Abstract

This drive may be used for operating a locking bolt 66 or for adjusting a throttle valve, or a vehicle headlight or the like. The drive comprises a motor 12 and a transmission 30 for converting the rotary movement of the motor into a reciprocating movement of the element 66. The worm-wheel 16 moves between limit switches (not visible) and a peg 50 on the wheel moves the bolt 66 through lost-motion levers 44, 54.

Description

SPECIFICATION A drives for adjusting a member, especially a component belonging to a motor vehicle State of the art The invention originates from a drive according to the type set forth in the main claim. A central locking device for vehicle doors is already known the driving motor of which operates a threaded spindle on which is arranged a so-called travelling nut which is displaced in one or the other direction according to the sense of rotation of the driving motor. A stay bolt connected to the travelling nut lies in a slot in a pivotally mounted double lever which is pivoted by the travelling nut.

The slot is arranged in the end region of one of the lever arms of the double lever and the other lever arm is operatively connected to the door lock. In order to achieve a sufficient pivotal movement of the lever arm acting on the door lock, the path of the nut must be very long so that the known device takes up a great deal of room. The difficulties in assembling this device are considerable because it is just in motor vehicle doors in the region of headlights and also in the engine compartment of motor vehicles that the space for the incorporation of such adjustment drives is generally extremely limited.

Advantages of the invention As opposed to this, the drive in accordance with the invention comprising the characterising features of the main claim has the advantage that it is of very compact construction so that numerous possible applications are provided.

As a further advantage it can be appreciated that such a drive operates reliably and is easily made to suit the particular requirements.

Advantageous further developments and improvements of the adjusting drive set forth in the main claim are made possible by the measures set forth in the sub-claims.

Drawing An embodiment of the invention is illustrated in the drawing and is described in detail in the following specification. Fig. 1 shows a diagrammatic representation in elevation of an adjusting drive belonging to a locking mechanism, wherein the locking mechanism is open and the adjusting drive is prepared for locking, Fig. 2 is a section through the adjusting drive according to Fig.

1 along the line ll-ll, Fig. 3 shows the adjusting drive in accordance with Fig. 1 during the locking movement and Fig. 4 shows the adjusting drive according to Fig. 1 during the unlocking movement.

Description of the embodiment An adjusting drive 10 illustrated in Fig. 1 has an electric driving motor 1 2 the armature shaft of which is formed as a drive worm 14.

The drive worm 1 4 meshes with a worm wheel 1 6 which is mounted by way of a bearing pin 18 in a gearbox 20. As Fig. 2 shows, three sliding contacts 24 pass through the base 22 of the gearbox 20 the contacts cooperating with a switching disc 26 which is arranged on the end 28 of the worm wheel 1 6 facing the base of the gearbox 22.The sliding contacts 24 and the switching disc 26 are arranged in the working current circuit of the electric driving motor 1 2. The construction of the switching disc 26 is so designed that, in cooperation with the sliding contacts 24, it so controls the motor that after the electric motor 1 2 is switched on the worm wheel 1 6 is rotated through 180 and then the driving motor 1 2 is switched off. Furthermore, the sense of rotation of the driving motor 1 2 can be reversed. When the electric motor is driven in the other sense it is likewise switched off when the worm wheel 1 6 has carried out an angular displacement of 180 .

Thus, in operation, the worm wheel 1 6 performs a swinging movement where it comes to rest in its two limit positions out of which it can only be moved by starting the electric motor once again by means of an operating switch.

Moreover, the adjusting drive has a transmission 30 for intermittent motion and a push rod 32 operatively connected to the transmission 30, which acts on a locking mechanism 34, and which forms a part of a cover element which is associated with an opening in a vehicle bodywork. Such covering elements are, for example, formed by motor vehicle doors, the engine bonnet of a motor vehicle, the boot lid or by a flap which covers a fuel filling pipe arranged in an alcove in the bodywork.

The transmission 30 for intermittent motion is likewise incorporated in the gearbox 20.

The transmission 30 for intermittent motion comprises an abutment pin 36 which projects from the surface 38 of the worm wheel 1 6 which is remote from the switching disc 26.

Moreover, the transmission 30 for intermittent motion comprises an arm 40, acting as a twoarmed lever, which is pivotable about a pin 42 rigidly connected to the gearbox base 22.

In a central position illustrated in Fig. 1, one of the lever arms 44 extends towards the bearing pin 1 8 of the worm wheel 1 6 and thus intersects an arc 46 which the abutment pin 36 traverses when it is moved out of one of its limit positions illustrated in Fig. 1 into its other limit position illustrated in dotted lines in Fig. 1. In so doing, the cylindrical wall regions of the pin 36 cooperating with one lever arm 44 of the arm 40 form abutment surfaces 48 and 50 by which one of the lever arms 44 of the arm 40 is pivoted towards one side or the other about the pin 42. This swinging movement is, of course, also performed by the other lever arm 52 which extends on the side opposite to the lever arm 44 with reference to the pin 42.A single arm intermediate lever 54 is pivotally mounted with respect to the base of the gearbox 22 on the pin 42 above the arm 40.

The intermediate lever 54 extends substantially in the same direction as the other lever arm 52 of the arm 40. Like the arm 40, the intermediate lever 54 has a pin 42 passing through it and together with the arm 40 is secured against axial loosening by a locking plate 56. The free end 58 of the intermediate lever 54 is made in the form of a fork and consequently has two prongs 60 and 62 arranged at a distance from each other. A driving pin 64, which is rigidly connected to the push rod 32, is located between the two prongs 60 and 62 of the intermediate lever 54. The push rod 32 is operatively connected to a latch element 66 which, together with a lock catch 68, forms the locking mechanism 34. When the adjusting drive is connected to the cover element, the lock catch 68 is mounted rigidly with respect to the body.

However, it is also possible to rigidly apply the adjusting drive to the body and to connect the lock catch 68 to the cover element. The recess 70 in the free end region 58 of the intermediate lever 54 is so designed that the intermediate lever 54 can be pivoted out of its limit position illustrated in Fig. 1 into its other limit position which is illustrated in dotted lines in Fig. 1. The arm 40 and the intermediate lever 54 are independent of one another to a certain extent and are thus pivotable on the pin 42 with respect to each other as desired. However, in operation of the apparatus, the pivoting of the intermediate lever 54 is caused by the arm 40.For this purpose, the other lever arm 54 of the arm 40 has two upwardly extending lugs 72 and 74 (see particularly Fig. 2) which project into the pivotal plane of the intermediate lever 54 and form driving tongues cooperating with the intermediate lever 54. The distance between the cheeks 76 and 78 of the lugs 72 and 74 facing one another is greater than the width of the intermediate lever 54. Moreover, the intermediate lever 54 is so arranged that it is located between the two cheeks 76 and 78 of the lugs 72 and 74. When the adjusting drive is not in operation, the arm 40 is always located in the central position illustrated in Fig. 1. Also, leaf springs 82 and 83 engage the lever arm 44 at its two opposite side surfaces 80 in the pivotal direction, the leaf springs being connected to the gearbox 20 through posts 84.The leaf springs 82 and 83 are pretensioned and matched to one another so that, with the adjusting drive switched off, they hold the arm 40 in its central position illustrated in Fig. 1. The side surfaces 80 form countershoulders which cooperate with the abutment regions 48 and 50 on the abutment pin 36.

The described adjusting drive operates as follows: When the locking mechanism 34 is to be brought out of the unlocked position illustrated in Fig. 1 into its locking position, the electric motor is switched on whereby the working current circuit is prepared through known electrical switching elements so that the worm wheel 46 is rotated in the direction of the arrow 86 (Fig. 1). After a predetermined angular rotation of the worm wheel 16, the abutment region 48 on the abutment pin 36 abuts against one side surface 80 of one of the lever arms 44 and entrains the latter by overcoming the increasing counterforce of the leaf spring 83.On pivoting of one of the lever arms 44 the other lever arm 52 is also pivoted and the cheek 78 on the lug 74 entrains the intermediate lever 54 which at the same time forms a driven element of the adjusting drive 1 0. The arm 44 is pivoted by the abutment pin 36 until the abutment pin 36 has reached its position illustrated in Fig.

3 and releases one of the lever arms 44 of the arm 40. In this position, the intermediate lever 54 has been pivoted out of its first reverse position illustrated in Fig. 1 into its second reverse position illustrated in dotted lines in Fig. 1, whereby, through the driving pin 64, it has pushed the push rod 32 forming an element for transmitting the movement so far in the direction of the arrow 65 (Fig. 3) that the driving pin 64 is located in the position illustrated in dotted lines in Fig.

1. In this position, the control element 66 of the locking mechanism 34 enters the lock catch 68 and thus arrives in its locking position. When the abutment pin 36 or its abutment region 48 releases one of the levers 44 of the arm 40, the leaf spring 82 is completely relaxed whereas the other leaf spring 83 has reached its maximal tension (Fig. 3).

Thus, the leaf spring 83 will then act on one of the lever arms 44 under its greatest tension and will force the arm 40 once again into its central position shown in Fig. 1 wherein the other leaf spring 82 acts as a counter-bearing.

However, only the arm 40 is adjusted by this return movement. Pivoting of the intermediate lever 54 does not occur because the distance between the two cheeks 76 and 78 on the lugs 72 and 74 has been appropriately designed. However, the worm wheel 1 6 moves into its one final position illustrated in dotted lines in Fig. 1. Thus, in the locking position, the abutment pin 36 belonging to the transmission 30 for intermittent movement is located in the position illustrated in dotted lines in Fig. 1. In order to open the locking mechanism 34 once again, the electric motor 1 2 must be switched on once again.Moreover, through known switching means, the working current circuit for the electric motor 1 2 has been so prepared that the worm wheel 1 6 is then rotated in the direction of the dotted arrow 88 in Fig. 1. After a predetermined angular rotation of the worm wheel 16, in which no variation of the locking mechanism 34 takes place, the abutment region 50 on the abutment pin 36 again engages the arm 40 located in its central position or engages one of its lever arms 44 and urges the latter out of the central position in the direction of the arrow 88 (Fig. 4).Of course, the other lever arm 52 of the arm 40 is also pivoted at the same time whereby the cheek 76 on the lug 72 pivots the intermediate lever 54 out of its position illustrated in dotted lines (Fig. 1) whereby the push rod 32 is urged in the direcion of the arrow 90 through the driving pin 64 and the prong 60 on the intermediate lever 54 and the unlocking movement for the locking mechanism 34 is initiated. The pivoting of the arm 40 then takes place so that the tension of the leaf spring 82 increases whilst the leaf spring 83 is increasingly untensioned.

When the transmission 30 for intermittent movement has reached its position illustrated in Fig. 4, the abutment pin 36 moves out of the pivotal region of one of the lever arms 44 and thus releases the arm 40. In this position, the locking mechanism 34 is again completely unlocked and reaches the position illustrated in Fig. 1. The abutment pin 36 moves once again into its limit position illustrated in Fig. 1 and the then strongly tensioned leaf spring 82 resets the arm 40 again into its central position without moving the intermediate lever 54 out of its reverse position in so doing.

In the regions where one of the lever arms 44 cooperates with the abutment pin 36, the side surfaces 80 on one of the lever arms 44 are so designed that slide curves 92 and 94 are produced which, acting as counter-shoulders cooperate with the abutment regions 48 and 50 on the abutment pin 36. In so doing, the slide curves 92 and 94 are so designed that the intermediate lever 54 or the push rod 32 performs the stroke 96 necessary for the unlocking movement or for the locking movement. From the above, it is also apparent, that a worm drive 14, 1 6 is operated by the driving motor 1 2 which acts on a transmission 30 for intermittent movement. Furthermore, the transmission 30 for intermittent movement converts the rotary motor movement into a pivotal movement which acts on the component 66 to be adjusted through the intermediate lever 54 acting as a driven element.

Due to the uncoupling between the arm 40 and the intermediate lever 54 over a predetermined pivotal angle and/or due to the uncoupling between the abutment pin 36 and one of the lever arms 44, the locking mechanism 34 can also be actuated by hand when an electrical actuation is not possible or is not desired.

Claims

1. A drive for adjusting an element, especially a component forming part of a motor vehicle, such as for example a locking element forming part of the locking mechanism of a cover element associated with a bodywork element, a throttle valve, a headlight or the like, comprising a driving motor and comprising means for converting the rotary movement of the motor into a pivotal movement of a driven member operatively connected to the element to be adjusted, characterised in that, a transmission for intermittent movement is arranged between the driving motor and the driven element.

2. A drive according to claim 1 characterised in that, the transmission has an abutment movable over at least a porion of an arc and which pivots an arm operatively connected to the element to be adjusted.

3. A drive according to claim 2 characterised in that the arm is formed as a two-armed lever one lever arm of which cooperates with the abutment and the other lever arm of which is operatively connected to the element to be adjusted.

4. A drive according to claim 3 characterised in that an intermediate lever preferably on a pin forming the pivotal axis for the twoarmed lever is pivotally arranged in a plane parallel to the pivotal plane of the arm wherein the intermediate lever extends substantially in the direction of the other lever arm and that the other lever arm has at least one driving member which cooperates with a shoulder on the intermediate lever.

5. A drive according to claim 4 characterised in that, at its free end, the intermediate lever is made fork-shaped and that a driving pin is located between the two prongs of the fork and which is rigidly connected to a transmission element operatively connected to the element to be adjusted.

6. A drive according to one of claims 4 or 5 in which the sense of rotation of the driving motor is reversible, characterised in that the abutment provided with the two abutment regions performs a pivotal angle of less than 360 , preferably 180 and that one of the lever arms has two countershoulders cooperating with the abutment regions on the abutment.

7. A drive according to claim 6 characterised in that the other lever arm has two cheeks acting as driving pin shoulders arranged at a distance from one another and which project into the pivotal plane of the intermediate lever, that the intermediate lever is arranged between the two cheeks and that the extension of the intermediate lever measured in the pivotal direction is less than the distance between the cheeks.

8. A drive according to claim 7 character ised in that the distance between the two cheeks permits a resetting of the arm out of each limit position into a central position without the intermediate lever moving out of its located limit position.

9. A drive according to claim 8 characterised in that the pivoting of the arm out of its central position into its two limit positions takes place against a return force.

10. A drive according to claim 9 characterised in that, in its central position, the arm is influenced at its sides opposite to one another in the pivotal direction by the force of a respective pre-tensioned spring element.

11. A drive according to one of claims 9 or 10 characterised in that, at its free end cooperating with the abutment, one of the lever arms has a slide curve matched to the particular limit position for each pivotal direction.

1 2. A drive according to one of claims 2 to 10 characterised in that a worm gear is arranged between the driving motor and the transmission for intermittent movement.

1 3. A drive according to claim 12 characterised in that an end surface of the worm wheel is provided with the abutment for the arm.

14. A drive according to claim 1 3 characterised in that a switching disc cooperating with sliding contacts for influencing the rotational angle of the worm wheel is preferably arranged on the end surface of the worm wheel remote from the abutment and that the switching disc and the sliding contact are arranged in the working current circuit of the driving motor.

1 5. A drive for adjusting a member, such as a component forming part of a motor vehicle, substantially as herein described with reference to the accompanying drawings.