[0001] The present invention relates to a hinge mechanism for mounting together two plates
in a coin testing mechanism. It is especially concerned with a hinge mechanism for
mounting the flight deck of a coin testing mechanism.
[0002] In a coin testing mechanism a passageway for coins is usually formed by two closely
spaced plates. A track carried by one of the plates supports the coins on their edges
and defines the path which coins follow between the plates. Coin testing devices are
arranged at positions alongside the path. Sometimes coins become jammed in the mechanism
and it is necessary to provide means for separating the plates sufficiently to allow
the jammed coins to fall from the track. In the known arrangements the plates are
joined to one another by a simple hinge and a mechanism is provided for swinging the
plates apart about the hinge when a coin is jammed.
[0003] The space available for a coin mechanism in a vending machine is often limited, particularly
the depth from front to back. It has been found that in some instances there is insufficient
depth to allow the plates to be swung apart sufficiently for coins close to the hinge
axis to be released. The aim of the present invention is to provide a mechanism which
overcomes this problem.
[0004] According to the present invention there is provided an assembly comprising a hinge
mechanism connecting two plates, the hinge mechanism comprising a hinge pin mounted
parallel to the plates for movement in a slot perpendicular to the plane of one of
the plates, the other plate being pivotally mounted about the axis of the hinge pin,
first biasing means biasing the plates together about the hinge axis and second biasing
means biasing the hinge pin towards the said one plate, actuating means being operable
to cause the plates to pivot about the hinge axis against the action of the first
biasing means and to move apart at the hinge axis against the action of the second
biasing means.
[0005] Conveniently the first biasing means may comprise a coil spring disposed around the
hinge pin and bearing on the one hand against part of the one plate or a part carried
by the said one plate and on the other hand against the other plate. The second biasing
means may comprise a leaf spring carried by the one plate and coupled to the hinge
pin. The coupling may conveniently be provided by a coil spring serving as the first
biasing means.
[0006] . The actuating means may be a lever pivoted on the one plate and carrying a cam
surface which cooperates with a cam follower surface on the other plate to force the
plates apart when the lever is operated.
[0007] An embodiment of the invention will now be described by way of example with reference
to the accompanying drawings of which:-
Figure 1 shows two plates of a coin mechanism connected by a hinge mechanism according
to the invention;
Figure 2 shows a back view of one of the plates of Figure 1;
Figure 3 shows a horizontal section on the line III-III of Figure 2;
Figure 4 shows a horizontal section on the line III-III with the plates in a different
position relative to one another;
Figure 5 shows a horizontal section on the line III with the plates in yet another
position, relative to one another;
Figure 6 shows a side elevation of the mechanism of Figures 1 to 5; and
Figure 7 shows a vertical section on the line VII-VII of Figure 5.
[0008] Referring to the drawings, these show part of a coin testing mechanism 11. In Figure
1 the parts are shown opened out more than they would be in normal everyday use. The
mechanism does however permit the parts to be opened out as far as is illustrated
for ease of cleaning. The mechanism comprises two plates 12 and 13 connected together
by a hinge mechanism 14. Rails 15 and 16 carried by the plates 13 and 12 provide a
coin track which supports the coins on their edges and define, when the two plates
12 and 13 are closed together, a zig-zag coin path 17 through the mechanism. Coins
inserted into the mechanism through a hopper 18 roll under gravity along the track
15, fall off its lower end onto track 16, roll down the track 16 and fall off its
lower end into the lower part 40 of the coin mechanism (see Figure 7). Alongside the
coin path are located the various coin testing devices, for example inductive sensor
39 as shown in Figure 2 of the kind described in our patent No. 1,397,083, which determine
the authenticity and the denomination of the coins inserted.
[0009] ' The hinge mechanism 14 comprises a hinge pin 19 which passes through two vertically-spaced
lugs 20 on the plate 12. The ends of the hinge pin 19 are received in slots 21 in
two vertically-spaced lugs 22 on the plate 13. The slots 21 extend in a vertical plane
perpendicular to the plane of the plate 13. Thus the hinge pin 19 serves to connect
the plates 12 and 13 together and allow rotational movement relative to one another
about the hinge axis and translational movement of the plates 12 in a direction perpendicular
to the plane of the plate 13.
[0010] The plates 12 and 13 arc-biased together into the closed position by means of a coil
spring 23. The central part of the coil spring is formed into a loop 24 which bears
against the edge 25 of the plate 12. The ends 26 of the wire of the coil spring 23
extend through holes 27 in the plate 13 and are fixed to a leaf spring 28. The leaf
spring 28 is carried on posts 29 on the back of the plate 13. The free end of the
leaf spring 28 which carries the ends 26 of the coil spring 23 is spaced from the
back of the back plate 13 and acting through the coil spring 23 holds the hinge pin
19 at the bases of the slots 21 in the lugs 22. Thus in the normal condition the two
plates are close together at the hinge axis and lie parallel to one another.
[0011] For separating the plates an actuating mechanism in the form of a lever 31 is provided.
The lever is pivotally mounted on a post 30 carried by the plate 13 so as to rotate
about an axis normal to the plane of the plate 13. At one end the lever 31 has an
operating handle 32 which depending on the particular coin mechanism in which it is
used, may be operated by the person using the vending machine either directly or indirectly
through a linkage. The other end of the lever 31 carries a cam surface 33.
[0012] A boss 34 on the plate 12 projects across the gap between the plates and through
an opening 38 in the plate 13. The boss carries a cam follower surface 35 which is
inclined relative to the plane of the plate 12.
[0013] The lever 31 is biased by a spring 36 so that the operating handle 32 is normally
in the raised position and the cam portion 33 is situated opposite the part of the
boss 34 which has a lower height relative to the plate 12 (the left hand end as viewed
in Figure 3). When the operating end of the lever 32 is depressed the cam portion
33 rides up the ramp formed by the cam follower surface 35 as it moves to the right
as viewed in Figures 3, 4 and 5. This action causes the plates to pivot about the
axis of the hinge from the normal closed parallel position of Figure 3 into the position
shown in Figure 4 in which the plates are spaced apart at the left hand edges. The
relative strengths and configurations of the springs 23 and 28 are such that the force
required to produce rotation about the hinge axis is less than is necessary to cause
deflection of the leaf spring. When the plates reach the position shown in Figure
4 the free edge of the plate 12 strikes a fixed abutment 38 which may be part of the
casing of the coin mechanism. This prevents further rotation of the plate 12 about
the hinge axis. Further rotation of the lever 31 about its pivot axis causes the cam
follower to ride up the less steeply sloping portion of the cam surface 35. The plate
12 rotates about its point of contact with the abutment 38 causing the hinge pin 19
to move outwardly in the slots 21 and the leaf spring 28 to be deflected into the
position shown in Figure 5. Thus the spacing between the plates at the side adjacent
the hinge 19 is increased.
[0014] It will be understood that when a coin is jammed in the mechanism shown in the drawings
it can be released by operating the lever 31 to separate the plates and allow the
coins to fall from the track. The mechanism shown in the drawings has the advantage
that when a coin is jammed close to the hinge axis separation of the plates sufficient
to allow the coin to fall from the track can be achieved even though the amount by
which the plates can be separated at the left hand end is limited.
[0015] Modifications of the design described above are possible without departing from the
scope of the present invention. For example we have found that it is possible to produce
separation of the plates at the hinge pin without the use of a fixed abutment 38.
By arranging the spring forces of the cantilever spring 28 and the coil spring 23
to balance one another, both plates can be caused to separate substantially parallel
to one another by the cam 33. We have found that a cam follower surface 35 which has
a single slope is particularly suitable for this arrangement, that is to say the flat
area for the final portion of the cam surface is eliminated.
1. An assembly comprising a hinge mechanism (14) for a coin testing mechanism connecting
two plates (12,13) characterised in that the hinge mechanism comprising a hinge pin
(19) mounted parallel to the plates for movement in a slot (21) which extends generally
perpendicular to the plane of one (13) of the plates, the other plate (12) being pivotally
mounted about the axis of the hinge pin, first biasing means (23) biasing the plates
together about the hinge axis and second biasing means (28) biasing the hinge pin
towards the said one plate, actuating means (31) being operable to cause the plates
to pivot about the hinge axis against the action of the first biasing means and to
move apart at the hinge axis against the action of the second biasing means.
2. An assembly according to claim 1 characterised in that the first biasing means
comprises a coil spring (23) disposed around the hinge pin and bearing on the one
hand, against part of the one plate or a part (28) carried by the said one plate and,
on the other hand, against the other plate.
3. An assembly according to claim 1 characterised in that the second biasing means
comprises a leaf spring (28) carried by the one plate and coupled to the hinge pin.
4. An assembly according to claim 3 characterised in that the coupling is provided
by a coil spring (23) disposed around the hinge pin and serving as the first biasing
means.
5. An assembly according to claims 1, 2, 3 or 4 characterised in that the actuating
means is a lever (31) pivoted on the one plate and carrying a cam surface (33) which
co-operates with a cam follower surface (35) on the other plate to force the plates
apart when the lever is operated.
6. An assembly according to any of the preceding claims characterised in that the
relative strengths and configurations of the biasing means are such that the force
required at the actuating means to produce rotation about the hinge axis is less than
is necessary to cause displacement of the hinge pin away from the said one plate.
7. An assembly according to claim 6 characterised by a housing having an abutment
(38) which is engaged by the edge of the said other plate remote from the hinge to
limit the rotation of the said other plate about the hinge pin.
8. An assembly according to any of claims 1 to 5 characterised in that the relative
strengths and configurations of the biasing means are such that the force required
at the actuating means to produce rotation about the hinge pin is equal to the force
required to cause displacement of the hinge pin away from the said one plate.
9. A coin testing apparatus comprising first (12) and second (13) plates defining
a passageway (17) for the movement there along of coins to be tested and hinge means
(14) interconnecting said plates to permit pivotal movement thereof away from each
other for removal of a body jammed in said passageway, characterised by means (21)
permitting translatory movement of said plates away from each other at least in the
region of the hinge means.