BACKGROUND OF THE INVENTION
[0001] The present invention relates to a push buttom assembly which has been specifically
designed for controlling glass raising and lowering devices in motor vehicles.
[0002] As is known, motor vehicles provided with electric glass raising and lowering devices
usually comprise a push button assembly, including several push buttons, which are
operatively coupled to controlling switches, for switching on and off the mentioned
devices.
[0003] In known push button assembly embodiments power particles, moisture and the like
may frequently enter inside the push buttons so as to impair a proper electrical contact
of the microswitches.
[0004] On the other hand, known push button assemblies in which the electrical wiring section
is tightly separated from the other component parts of the assembly, have not be found
as completely satisfactory, since these push buttom assemblies are very complex from
the constructional standpoint which negatively affects the reliability of the push
button assembly itself.
SUMMARY OF THE INVENTION
[0005] Accordingly, the task of the present invention is to overcome the above mentioned
drawbacks, by providing a push button assembly structure in which all of the electrical
component parts are tightly separated from the outside environment, thereby providing
a very high reliability in operation, with a comparatively simple construction.
[0006] Within the scope of the above mentioned task, a mai object of the present invention
is to provide such a push button assembly on the push buttons of which is possible
to represent letters, patterns and the like while preventing powder and moisture particles
from absolutely penetrating inside said assembly.
[0007] Another object of the present invention is to provide such a push button assembly
structure which comprises a very reduced number of easily and quickly assemblable
component parts.
[0008] Yet another object of the present invention is to provide such a push button assembly
structure which may be easily made starting from easily commercially available elements
and materials and which, moreover, is very competitive from a mere economic standpoint.
[0009] According to one aspect of the present invention, the above mentioned task and objects,
as well as yet other objects, which will become more apparent thereinafter, are achieved
by a push button assembly structure, which has been particularly designed for controlling
motor vehicle glass raising and lowering devices, comprising a box-like casing adapted
for coupling to the electric wiring board, supporting operating microswitches, characterized
in that it further comprises a membrane which may be tightly superimposed on said
board and is adapted for operating as a resilient return element for operating push
buttons which are accessible from the outside of said box-like casing and slidingly
guided by throughgoing holes formed through said box-like casing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Further characteristics and advantages of the present invention will become more
apparent from the following detailed description of a push button assembly structure,
particularly designed for operating motor vehicle glass raising and lowering devices
according to the present invention, which has been illustrated, by way of an indicative
but not limitative example, in the figures of the accompanying schematic drawings
in which:
figure 1 is a perspective exploded view illustrating the push button assembly according
to the present invention;
figure 2 is a top plan view of the push button assembly;
figure 3 is a cross-sectional view of the push button assembly according to the invention
taken along the line III-III of fig.2;
figure 4 is a cross-sectional view of the push button assembly according to the invention,
taken along the broken line IV-IV of fig.2; and
figure 5 is another cross-sectional view illustrating a push button assembly according
to the present invention provided with a board or base including a spacer element.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] With reference to the figures of the accompanying drawings, the push button assembly
according to the present invention, which has been overally indicated at the reference
number 1, essentially comprises a box-like casing 2, which preferably though not
necessarily has a parallelepipedal shape, which may be coupled, at the top thereof,
to an electric wiring board which has been indicated overally at the reference number
3 in figure 1.
[0012] According to a preferred embodiment, said electrical wiring board or base comprises
a supporting foldable small plate 4 therewith a flexible printed circuit 5 is associated
which is housed inside said foldable small plate 4 as said plate is bent to its final
shape.
[0013] On said small plate 4 coupling members 6 are provided adapted for receiving the pins
of the microswitches 7 for controlling the motor vehicle glass raising and lowering
devices, which switches will be directly coupled at the insertion time.
[0014] More specifically, the microswitches 7 may be of the single stage type, that is which
directly control the glass lowering and raising devices as they are operated, or of
the double stage type that is which provide a first operation in which the electrical
contact is held for the overall time the push buttons are pressed and a second operation
which is obtained by exerting a greater pressure on the push buttons.
[0015] In this latter condition, as the pressure on the push button is released, the glass
will be continuously displaced as far as it will reach an end of stroke position.
[0016] In this connection, it should be apparent that the type of used microswitch does
not modify the invention concept.
[0017] The main feature of the present invention is that the push button assembly comprises
a resilient membrane, indicated overally at the reference number 10, which may be
superimposed on the electric wiring board or base 3 and is provided with shaped portions
11, at the zone thereat said microswitches are arranged.
[0018] More specifically the mentioned shaped portions 11 are provided with a base portion
13, encompassing the respective microswitch, thereon there is superimposed as essentially
frustum of cone shaped portion 13 provided for resiliency purposes, as it will be
disclosed in a more detailed way hereinafter, and thereon a stiffening cylindrical
portion 14 is arranged.
[0019] The membrane 10 is firstly provided as a tightness element which practically separates
from the outside environment the region thereat there are formed the electrical wirings.
[0020] Moreover, the shaped portions 11 are specifically designed to operate as a resilient
return element for the microswitch operating push buttons, which are overally indicated
at the reference number 20.
[0021] In particular, the push buttons 20 comprise a substantially rigid intermediate body,
indicated at 21, which is coupled by contact to the mentioned cylindrical portion
14, on said body there being arranged a cap 22 having at least a translucid or semitrasparent
portion 23 provided for receiving patterns and the like.
[0022] The cap 22 is peripherically provided, at the edge portions thereof, with flanged
rims 24 adapted for operating as stop elements for the displacement of the push buttons
20, which are guided by throughgoing holes 25 formed through the top face of the box-like
casing 2.
[0023] The membrane 10 is advantageously made of a transparent or translucid material, so
as to allow for the light of a display lamp 30 to pass through, said lamp being housed
in a seat 31 defined by said membrane, preferably at the central region thereof.
[0024] Thus, it will be possible to light up the patterns formed on the push buttons 20,
while holding the electrical wiring circuits tightly separated from the outside environment.
[0025] Moreover the membrane 10 also acts as a resilient return element for the single push-buttons.
[0026] In fact the shaped portions 11 are provided, at the tops thereof, with a frustum
of cone shaped portions 13, which may be resiliently deformed as the push button 20
is pressed but which is able of recovering to its original shape thereby practically
acting as a resilient return element.
[0027] Thus the assembling of the push buttons will be greatly simplified, since conventional
spring elements for resiliently recovering the push buttons are completely omitted.
[0028] Figure 5 illustrates a push button assembly which is conceptually analogous to the
above disclosed push button assembly and which is provided, at the electrical wiring
board or base, with a spacer element indicated at 30.
[0029] From the above disclosure it should be apparent that the invention fully achieves
the intended task and objects.
[0030] In particular the fact is to be pointed out that a push button assembly has been
made in which the push buttons, which are accessible from the outside, are practically
tightly separated from the outside environment and from the electrical wiring components,
thereby preventing powder and moisture from absolutely entering the push button assembly
casing.
[0031] Moreover, the specific shape of the membrane provides the latter with a multioperation
characteristic since, in addition to the tightness function proper, said membrane,
which is made from a resilient material, also operates as a return element for the
single push-buttons.
[0032] Another important feature of the invention is the shape of the push buttons, or the
patterns formed thereon can be easily modified, since said push buttons are practically
formed by a cap which may be easily and quickly changed, thereby changing said patterns.
[0033] While the invention has been disclosed and illustrated with reference to a preferred
embodiment thereof, it should be apparent that it is susceptible to several variations
and modifications, all of which will come within the invention scope.
[0034] For example the push buttons may also be made from a soft material.
1- A push button assembly structure, specifically designed for controlling motor
vehicle glass raising and lowering devices, comprising a box-like casing, adapted
for coupling to the electric wiring board or base, supporting operating microswitches,
characterized in that it further comprises a membrane adapted to be tightly superimposed
on said board and to operate as a resilient return element for the operating push
buttons, accessible from the outside of said box-like body slidingly guided by throughgoing
holes formed through said box-like casing.
2- A push button assembly structure according to claim 1, characterized in that said
membrane is provided with shaped portions for housing said microswitches.
3- A push button assembly structure according to the preceding claims, characterized
in that said shaped portions are provided with a base portion, encompassing said microswitches,
a frustum of cone shaped portion above said base portion, adapted to act as a resilient
element and a substantially cylindrical portion above said frustum of cone shaped
portion.
4- A push button assembly structure according to one or more of the preceding claims,
characterized in that said membrane is made of a translucid material.
5- A push button assembly structure, according to one or more of the preceding claims,
characterized in that said membrane defines a seat for housing an illumination lamp.
6- A push button assembly structure according to one or more of the preceding claims,
characterized in that said push buttons are provided with an intermediate essentially
rigid body, or optically transparent material, adapted to be coupled by contact to
said cylindrical portion of said shaped portions and supporting a cap accessible
from the outside of said box-like casing.
7- A push button assembly structure according to one or more of the preceding claims,
characterized in that said cap is provided with at least a translucid portion.
8- A push button assembly according to one or more of the preceding claims, characterized
in that said cap is provided with patterns or the like for identifing the function
of the corresponding push button.
9- A push button assembly according to one or more of the preceding claims, characterized
in that said electric wiring board consists of a foldable plate thereto there is coupled
a flexible printed circuit, adapted to be housed inside the zone encompassed by said
plate in its folded condition.
10- A push button assembly structure according to one or more of the preceding claim,
characterized in that it comprises, under said electric wiring board, a spacer element.