Mechanical counter

A plurality of presettable digit wheels are rotatably mounted on a first axis. Each of said wheels is rotatable to a plurality of preset positions corresponding to respective values of an associated digit position of a preselected count. Retaining means retain said presettable wheels in said preset positions during a counting operation of the counter. A signal generator comprises axially movable cam follower means arranged to generate a signal when said counter has counted to said preselected count. A plurality of presetting members are associated with respective ones of said presettable wheels and pivoted to a stationary first pivot. At portions remote from said first pivot, said presetting members are engaged by a guide member, which is pivotally movable between first and second positions to move said presetting members about said pivot out of and into engagement with said presettable wheels. First spring means are adapted to urge said guide member to said first position. The presetting members are displaceable relative to said pivot and said guide member to rotate said presettable wheels when said presetting members are in engagement with said presettable wheels.

BACKGROUND OF THE INVENTION 
This invention relates to a presetting mechanism for mechanical counters, 
preferably counting-up counters, in which the preset count is stored and 
which comprise a signal generator having axially acting cam followers. 
Such presetting mechanisms are known for mechanical counters in which the 
preset count is stored and in which in response to a counting to the 
preset count the cam followers perform cumulative axial operations whereby 
a signal-generating contact is closed. In this arrangement, a high torque 
is required when the preset count is reached so that the mechanical 
counter requires strong drive means, which are not required for the actual 
counting operation. 
Presettable counters have also the disadvantage that the counter must be 
set to zero before it can be preset. 
It is an object of the invention to eliminate the above-mentioned 
disadvantages and to provide for a presettable mechanical counter a 
presetting mechanism for presetting the counter to a count which is always 
visible. 
The presetting mechanism for a mechanical counter, preferably a counting-up 
counter, in which the preset count is stored and which comprises a signal 
generator having axially acting cam followers is characterized according 
to the invention in that presetting members are provided, which are 
pivoted on a fixed pivot and at a distance from the pivot are engaged by a 
rakelike guide member, which is pivotally movable to move said presetting 
member into engagement with the presettable digit wheels and spring-biased 
to an initial position, in which said presetting members are disengaged 
from said wheels. The guide member has teeth, which in an initial position 
of said member engage teeth of said wheels to hold them in position, and 
is integrally formed with a spring lug, which is slidable along the 
housing and urges the key-guiding member to its initial position. Owing to 
the use of multifunctional parts, this arrangement can be made at low cost 
while ensuring a high reliably of function and ease of operation.

In FIG. 1 of the drawing, the presetting mechanism is shown as well as its 
arrangement in the frame 1, which is provided with a cover 2. The latter 
has windows provided with magnifiers 3 for reading the count. It is also 
apparent that the guide member 4 is provided, which is pivoted in the 
frame 1 and snapped in a bearing bore 5. The guide member 4 carries a 
guide pin 6, which is axially parallel to the bearing hole 5 and on which 
presetting members 7 are guided. The presetting members 7 are also guided 
on a pivot 8, which is spaced from the guide pin 6 and fixed in the frame 
1. A tension spring 9 urges the presetting members to the basic position 
shown in FIG. 1. 
The tension spring 9 is connected at one end to the guide pin 6 and at the 
other end to a bracket 10, which is spaced from the pivot 8. As a result, 
the spring 9 can urge the presetting members 7 toward their position of 
rest as well as toward the teeth 11 of the presettable wheels 18. The 
guide member 4 is provided with retaining fingers 12, which are arranged 
like the tines of a rake and when the mechanism is in position of rest 
engage the teeth 11 to align the guide member 4 and to lock the 
presettable wheels 18. A leaf spring 13 is provided, which bears on an 
abutment 14 and urges the guide member 4 toward its position of rest, 
shown in FIG. 1. Rakelike detent springs 15 are integrally formed with the 
frame 1 and engage the teeth 11 while permitting the wheels 18 to be 
rotated in the presetting sense. 
As is shown in FIG. 2, the guide member 4 comprises an actuating lever 16, 
which extends out through the cover 2 and serves to pivotally move the 
guide member 4 by hand to a position for presetting. By means of the 
actuating lever 16, the retaining fingers 12 can be pivotally moved away 
from the teeth 11. At the same time, the pivotal movement of the guide pin 
6 causes the teeth 17 of the presetting keys 7a to engage the teeth 11 of 
the presettable wheels 18. 
It is apparent from FIG. 3 that the presetting members 7 can be actuated so 
that their teeth engage the teeth 11 of the presettable wheels 18 to rotate 
the latter toward the count to which the counter is to be preset. When the 
member 7 is depressed, the tension spring 9 is stressed so that it can 
return the member 7 to its initial position when the member 7 has been 
released. During this operation, the member 7 slides up on the side face 
20 of the teeth 11, owing to the widened guide slot 19, formed in the 
member 7 and receiving the guide pin 6, and is pivotally moved by the 
tension spring 9 about the pivot 8 while skipping the teeth 11. 
It is apparent particularly from FIG. 3 that each presetting member 7 is 
manually operable by a presetting key 7a, which is guided in the cover 2. 
Each presetting member 7 is constrained to follow the pivotal movement of 
the guide member 4 to a position in which the member 7 engages the teeth 
11 or is clear therefrom. 
Particularly in an arrangement in which the presettable wheels are held in 
their preset position during the counting operation, the presetting 
mechanism is combined with an axially actuated signal generator, which is 
shown more in detail in FIGS. 4 and 5. FIG. 5 is a fragmentary view 
showing a portion of FIG. 4 on a larger scale. Each presettable wheel 
which is provided with teeth 11, has associated with it a signalling gear 
22, which is mounted on the hub 21 of the presettable wheel, and is driven 
by an associated indicating wheel 24, which has a gear 23, shown in FIGS. 1 
to 3, in mesh with the associated gear 22. 
The signalling gear 22 has a hub, on which a cam follower ring 25 provided 
with projection 26 is axially slidably mounted. Each projection 26 extends 
through an aperture 27 of the associated signalling gear 22 into engagement 
with the end face 28 of the associated presettable wheel 18. By means of 
the projection 26 and the aperture 27, the cam follower ring 25 is 
non-rotatably coupled to the associated signalling gear 22. When the 
projection 26 is in registry with a signalling recess formed in the end 
face 28, the projection 26 falls into said recess and the cam follower 
ring 25 performs a signalling stroke. The signalling strokes of all cam 
follower rings 25 are actuated by the signalling rake 30, which bears on 
all cam follower rings 25 and is axially biased by a switch 37, which has 
been prestressed and click-stopped. 
The signalling rake 30 embraces the cam follower rings 25 at their hub 
portions and is axially slidably mounted on guide pins 32 and 33 above the 
axle 31 on which the presettable wheels are rotatably mounted and on a 
guide rod 34 below said axle. The guide rod 34 is fixed in the frame 1. 
The signalling rake 30 carries an inherently resilient detent 35. A switch 
37 has an actuating lever 36, which through the intermediary of a 
bell-crank lever 38 bears on said detent pawl 35. 
When the counter has counted to a preselected count which corresponds to 
the positions of the presettable wheels, the signalling rake 30 is 
displaced to such an extent that the bell-crank lever 38 disengages the 
surface 39, at which it previously engaged the detent 35. As a result, the 
actuating lever 36 is tripped to generate a signal. When the counter is in 
zero position, the bell-crank lever 38 can be returned. In that operation, 
the resilient detent 35 yields and then holds the bell-crank level 38 in 
position when the switch has been prestressed. To permit of an exact 
adjustment of the release position, the detent 35 bears under initial 
stress on a stop angle 40, which is integrally formed on the signalling 
rake 30. An adjustment of the release point is made possible because the 
pivot 41 for the bell-crank lever consists of a rotatable eccentric, which 
is connected to a ratchet. 
The present embodiment is mainly designed for the use of multi-functional 
components so that a maximum number of functions can be obtained with a 
minimum number of parts.