The invention relates to a keypad provided with push-buttons and to a knob equipped with such a keypad, in particular for a motor vehicle control panel.
There are currently many types of keypad for motor vehicle control panels, in particular for an instrument system.
In particular, there are keypads in which the buttons are not linked together and are each provided with guidance and foolproofing means for preventing them from jamming. Moulding of the guidance and foolproofing means into the front of the control panel is often delicate, and the same is true of the guide ribs of the buttons associated therewith. This involves successive adjustments in the moulds which are therefore complex and expensive to produce. Moreover, each button has to be mounted the correct way upon assembly, and this takes a lot of time.
There are also keypads comprising buttons that are not guided, but these have to withstand a high return force which is harmful to the button and adversely affects the ease of use.
In order to solve this problem, the invention proposes grouping the buttons together and positioning them in the keypad so as to facilitate use thereof without the need for foolproofing or guidance means.
More specifically, the object of the invention is a keypad for a control panel, in particular for a motor vehicle instrument system, comprising a front provided with openings through which a number of push-buttons are placed, each positioned facing a contactor fixed to a card, in which the buttons are linked together at least in groups of two to form a unitary set and are placed with respect to one another on the keypad such that each button can be moved individually and pushing thereof causes solely actuation of the contactor assigned to said button, without any effect on the contactors of the other buttons.
According to some preferred embodiments of the present invention:
- the buttons are secured to a common base arranged under the front so that pushing a given button to actuate its associated contactor causes the base to tilt, without jamming, about an axis that is essentially perpendicular to the pushing direction of said button and passes through at least one other button of the set of buttons;
- the buttons and their base are moulded in one piece by plastic injection moulding;
- the displacement travel of each button is between about 0.25 and 1.5 mm, preferably 0.5 mm;
- the base and the buttons are made of rigid or flexible material;
- the buttons are spaced apart from one another laterally by a few millimetres to a few centimetres, depending on the material used, and preferably by one millimetre to one centimetre;
- there may be two buttons or else three to form a triangle, for example an equilateral triangle, or else four to form a square. In the case of a triangle, the axis of rotation of the base passes through at least one button other than that pushed, the two other buttons if the triangle is equilateral. In the case of a square, the axis of rotation of the base passes through the button located opposite the pushed button.
The present invention also relates to a knob provided with a keypad as defined above, the buttons of which are arranged around a central thumb wheel which can rotate, and also to a motor vehicle control panel equipped with such a keypad or with such a knob.
Other features, details and advantages of the invention will emerge upon reading the description given with reference to the attached drawings given by way of example, in which:
FIG. 1 shows a perspective view of a keypad comprising two buttons according to the invention,
FIG. 2 shows an exploded perspective view of FIG. 1,
FIG. 3 shows a front view of FIG. 1,
FIG. 4 shows a sectional view of FIG. 1,
FIG. 5 shows another perspective view in which one button of the keypad has been pushed,
FIG. 6 shows a sectional view of FIG. 5,
FIG. 7 shows a perspective view of a variant embodiment of the invention in which the keypad has three buttons,
FIG. 8 shows a perspective view of a variant embodiment of the invention in which the keypad has four buttons,
FIG. 9 shows a partially cut-away perspective view of FIG. 8, and
FIG. 10 shows another perspective view in which a button of the keypad of FIGS. 8 and 9 has been pushed.
As shown in FIGS. 1 to 4, the keypad 10 of the present invention comprises a rigid base card 12 on which mechanical contactors 14 and light indicators 16 such as LEDs are mounted.
Each contactor 14 is associated with a button 20 mounted opposite it. The buttons 20 are grouped into a unitary set 22 and are moulded in one piece with a base 25 from rigid plastic material.
A front 30 made of rigid plastic is placed over this assembly and serves to keep the buttons in position. This front 30 has openings 32 for allowing access to the buttons 20. In the assembled position, as shown in FIGS. 3 and 4, the buttons 20 rest on the contactors 14 without actuating them, and the base 25 is pressed against the front 30.
During use, as shown in FIGS. 5 and 6, pushing a button 20, for example the button marked “OFF”, causes the latter to be pushed in a pushing direction that is essentially perpendicular to the base 25 and is indicated by the arrow F. This pushing takes place over a travel d that is more or less equal to 0.5 mm. Pushing the button 20 thus makes it possible to actuate the contactor 14 associated therewith. This pushing is accompanied by a rotation of the base 25 about an axis XX′ that is essentially perpendicular to said pushing direction F and passes through the other button, essentially at the point of contact between said other button and its associated contactor. This pivoting of the base 25 makes it possible to prevent the contactor other than the one associated with the pushed button from being actuated. Thus, pushing a button brings about displacement thereof and actuation solely of its associated contactor, without any effect on the other contactors. The rotation about the axis XX′ is almost imperceptible since the user does not see the other button move.
This mode of operation is also found in variant embodiments in FIGS. 7 to 10.
Thus, in FIG. 7, the keypad 10 has three buttons 20 which in the present case form an equilateral triangle. Pushing a button 20, illustrated by the arrow F, brings about both displacement of said button, and hence actuation of its associated contactor 14, and also pivoting of the base 25 about an axis XX′ that is essentially perpendicular to said pushing direction F and passes through the two other buttons. Only the contactor 14 of the pushed button 20 is actuated, the rotation of the base 25 preventing the other contactors 14 of the other buttons 20 from being actuated at the same time.
In these two embodiments, since the base 25 and the buttons 20 are moulded in one piece from rigid plastic, the buttons are spaced only slightly apart from one another, for example by between one millimetre and about one centimetre.
In FIGS. 8 to 10, a control knob 1 is equipped with a keypad 10 having four buttons 20 which are mounted in the present case in a square around a central thumb wheel 21 which can rotate. The four buttons 20 are independent of this rotating thumb wheel 21 and are mounted on a base 26.
As can be seen in FIG. 10, pushing a button 20 in a direction F brings about displacement of said button 20 over a travel of about 0.5 mm. This displacement also causes actuation of the contactor 14 associated with said pushed button 20, which may be verified for example by a light indicator 16 being lit, and also tilting of the base 26 about an axis XX′ that is essentially perpendicular to the pushing direction F of the button 20 and passes through the button located opposite the pushed button 20. The two buttons which are located next to the pushed button are pushed over a travel of a few tens of millimetres, for example 0.25 mm, without this having any influence on the operation of the keypad 10, and in particular without this causing actuation of their associated contactors. The user thus does not have the impression of pushing all the buttons at the same time. This also makes it possible to balance the base.
In this embodiment, the buttons are spaced apart from one another by one to a few centimetres.
However, it must be understood that these examples are given solely by way of illustration of the object of the invention, and do not in any way represent a limitation thereof.
It is thus possible to create a keypad having n buttons, said buttons being distributed for example in a circle in the form of a block, it being possible for each button to be moved individually.
It is also possible for the base to be flexible, in particular if the buttons are spaced very far apart from one another or if there are a very large number of buttons.
Patent Application
20050061640
