GB1565239A

GB1565239A - Resetting device for registers

Info

Publication number: GB1565239A
Application number: GB5072576A
Authority: GB
Original assignee: Societe Internationale de Mecanique Industrielle SA
Current assignee: Societe Internationale de Mecanique Industrielle SA
Priority date: 1975-12-12
Filing date: 1976-12-06
Publication date: 1980-04-16
Also published as: IT1074969B; DE2653324A1; DE2653324C3; DE2653324B2; FR2335001A1; FR2335001B1; ES453127A1

Description

(54) RESETTING DEVICE FOR REGISTERS (71) We, SOCIETE INTER NATIONALE DE MECHANIQUE INDUSTRIELLE S.A., a Company of Luxembourg, of 37 Rue Notre-Dame, Luxembourg (Grand Duche de Luxembourg) do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention concerns a device for resetting a numbered drum register.

An object of the present invention is to provide a device for resetting a numbered drum register such as a daily mileage meter of a vehicle. Registers of this type, such as vehicle mileage meters, basically comprise identical rotating drums, graduated W9, set side by side along a single axis. One of the end drums is connected to a drivedevice which is, for example, sensitive to the distance travelled, and internal gear and ratchet means produce the rotation of the other drums in such a way that a drum passes from one graduation to another, i.e.

moves through one tenth of a revolution, when the preceding drum has completed one complete revolution.

The assembly of drums is mounted on a shaft which remains stationary while the drums are arranged to be driven from a driving-device. The shaft is arranged to be rotated when desired through outside intervention, for example by the driver where a daily mileage meter is concerned, the arrangement being such that when the shaft is rotated by one revolution in a given direction, the zero-graduations of the drums all align on a set mark coincident with the dial provided on the vehicle control-panel.

Rotation of the shaft consequently causes the resetting of the register.

Classical resetting devices comprise a control means such as a button rotatable directly with the shaft of the meter. To zero the meter, the driver must turn the button until the zeros appear on the dial. This operation is inconvenient, and it is desirable that it should be replaced by simple pressure on a button.

To this end resetting devices have been proposed comprising a toothed-wheel keyed onto the register-shaft directly driven by a rack moving positively with a press-button.

Pressure on this button moves the rack and turns the toothed-wheel through one complete revolution, thus effecting the resetting of the register. The rack is subjected to the action of a spring which later returns it to its original position.

Devices of this type have two major disadvantages. On the one hand, as the rack must initiate one complete revolution of the wheel, it must, of necessity, be lengthy, thus increasing the size of the device. On the other hand, the shaft must not rotate when the rack returns to its original position under the action of the return-spring, thus entailing the provision of a declutchingdevice which increases the cost of the instrument.

The invention aims at providing a resetting device which does not have the above mentioned disadvantages thereby enabling the device td be small in size and obviating need for a declutching device.

Thus according to the present invention there is provided a device for resetting a numbered drum register comprising a toothed segment keyed onto said shaft and having teeth over an arc of less than 1800, and two racks of generally identical design set symmetrically on either side of said shaft and secured to a single control, the racks and the control being guided in their movement in a fixed bearer, said control being movable between two stops defining start and end of stroke positions, respectively and being biased towards said start position by a spring, the segment and the racks being designed and arranged such that the segment is only ever meshed with one of the racks and that, the toothed segment when the control is in either of said positions, is positioned so as to mesh with one of the racks.

Further, a declutching-device is not required since, during the return-stroke of the control the toothed segment meshes with one of the racks.

The invention will now be described further by way of example only with reference to the appended drawings, in which: Fig. 1 is a perspective-view of the returnto-zero device made in accordance with the invention, the daily-total meter being shown in part for the sake of clarity, and Figs. 25 are sectional views along the line A-A on Fig. 1, which show the positions successively taken by the movingparts of the device during the zeroingoperation.

Fig. 1 illustrates a resetting device of the invention and part of a daily-total meter which is required to be reset. The meter is of a known type and comprises several drums 1 graduated from 0 to 9, usually four in all.

The drums are arranged to be rotated by means of a dummy drum (not shown). The assembly is fitted onto a shaft 2 and gearand pawl-mechanisms produce the rotation of the drums 1, each drum turning ten times faster than that which is placed immediately to its left. When the meter is working normally to record mileage the shaft 2 remains stationary and may only rotate when actuated by the operator to return the drums to zero. This positive rotation by an operator brings about the alignment of the drums 1 with a set mark, and thus returns the meter to zero, provided that shaft 2 moves through one complete revolution.

The device covered by the invention aims at causing shaft 2 to make a complete revolution by simple pressure from the operator. The device thus comprises essentially a toothed segment 10 keyed to the end of shaft 2, the two racks 11 and 12 with a generally identical design disposed on either side of the segment 10.

The racks 11 and 12 are part of a block 13 arranged to be moved positively by means of a pressure-rod 14, having at its outer end a button 15 accessible to the operator. The block 13 is guided in its movement in a fixed bearer 16 having a base in which is provided an opening (not shown) for the passage and guidance of the lower part 18 of the rod 14.

A compression-spring 17, shown in Figs.

2-5, is arranged round the lower part 18 of the rod, that is between the face of the block 13 opposite the button 15 and the bottom of the bearer 16. The spring tends to force the block 13 away from the base of the bearer 16. A circlip 19 is fitted on the end of the lower part 18 of the rod, externally of the base of the bearer 16, to prevent the free end of the pressure-rod from passing into the bearer 16 through the opening in the base thereof.

A stop 20 (shown in Figs. 2-5) is also provided for the button 15, which limits the stroke of the rod when pushed by button 15.

The toothed segment 10 is designed so as to be capable of meshing with the rack 11, and it is shown alone, at rest, in Fig. 2.

Movement of the block 13 when thrust by pressure on button 15 (arrow P in Fig. 3) thus causes the rotation of segment 10 in the direction of the arrow adjacent thereto. The rack 12 which also undergoes this movement obviously remains inoperative since the segment 10 is only toothed over a limited angle, for example, about 1200.

The length of the rack 11 is calculated so that, when the pressure-rod 14 comes to the end of its stroke, in the position shown in Fig. 4, the segment 10 will have moved through exactly one-half of a revolution. At that point, the toothed portion of the segment 10 is out of mesh with rack 11 and is in position to mesh with rack 12.

At this stage, pressure on the button 15 is removed and the spring 17 acts, in the direction of the arrow R (Fig. 5), to bring back the block 13 and racks 11 and 12 to rest as in Fig. 2. As may be seen in Fig. 5, segment 10 is turned by rack 12 as the block 13 returns to the position of Fig. 2 under the influence of the spring 17. The length of the rack 12 is also calculated so that segment 10 shall have moved one half of a revolution when block 13 comes to rest. Segment 10, over the whole cycle, has thus made one complete revolution and is now back exactly to its starting-point, that is it is ready to mesh with rack 11 for another cycle.

In rotating, segment 10 takes with it the shaft 2 of the meter, and the return to zero is thus brought about since the shaft 2 will have made a complete revolution.

To summarise the operation of the device it will be seen that during the forward stroke of the control button 15, when pushed by the operator, the toothed segment meshes with one of the racks and moves through 1800, then, during the return-stroke of the control under the action of the spring, the toothed segment meshes with the other rack and again moves through 1800. One forward and return stroke thus corresponds to one complete revolution of the toothed segment and thus, of the shaft of the meter.

Thus a device according to the invention is much more compact that known devices, since the racks serve to move the toothed segment through 1800 and are thus much shorter than the single rack of current devices.

WHAT WE CLAIM IS: 1. A device for resetting a numbered drum register of the kind comprising rotary drums graduated from 0 to 9, set side by side, and fitted onto a common shaft which remains. fixed while the drums rotate, but

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

required since, during the return-stroke of the control the toothed segment meshes with one of the racks.

The invention will now be described further by way of example only with reference to the appended drawings, in which: Fig. 1 is a perspective-view of the returnto-zero device made in accordance with the invention, the daily-total meter being shown in part for the sake of clarity, and Figs. 25 are sectional views along the line A-A on Fig. 1, which show the positions successively taken by the movingparts of the device during the zeroingoperation.

Fig. 1 illustrates a resetting device of the invention and part of a daily-total meter which is required to be reset. The meter is of a known type and comprises several drums 1 graduated from 0 to 9, usually four in all.

The drums are arranged to be rotated by means of a dummy drum (not shown). The assembly is fitted onto a shaft 2 and gearand pawl-mechanisms produce the rotation of the drums 1, each drum turning ten times faster than that which is placed immediately to its left. When the meter is working normally to record mileage the shaft 2 remains stationary and may only rotate when actuated by the operator to return the drums to zero. This positive rotation by an operator brings about the alignment of the drums 1 with a set mark, and thus returns the meter to zero, provided that shaft 2 moves through one complete revolution.

The device covered by the invention aims at causing shaft 2 to make a complete revolution by simple pressure from the operator. The device thus comprises essentially a toothed segment 10 keyed to the end of shaft 2, the two racks 11 and 12 with a generally identical design disposed on either side of the segment 10.

The racks 11 and 12 are part of a block 13 arranged to be moved positively by means of a pressure-rod 14, having at its outer end a button 15 accessible to the operator. The block 13 is guided in its movement in a fixed bearer 16 having a base in which is provided an opening (not shown) for the passage and guidance of the lower part 18 of the rod 14.

A compression-spring 17, shown in Figs.
2. A device for resetting a numbered drum register substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

2-5, is arranged round the lower part 18 of the rod, that is between the face of the block 13 opposite the button 15 and the bottom of the bearer 16. The spring tends to force the block 13 away from the base of the bearer 16. A circlip 19 is fitted on the end of the lower part 18 of the rod, externally of the base of the bearer 16, to prevent the free end of the pressure-rod from passing into the bearer 16 through the opening in the base thereof.

A stop 20 (shown in Figs. 2-5) is also provided for the button 15, which limits the stroke of the rod when pushed by button 15.

The toothed segment 10 is designed so as to be capable of meshing with the rack 11, and it is shown alone, at rest, in Fig. 2.

Movement of the block 13 when thrust by pressure on button 15 (arrow P in Fig. 3) thus causes the rotation of segment 10 in the direction of the arrow adjacent thereto. The rack 12 which also undergoes this movement obviously remains inoperative since the segment 10 is only toothed over a limited angle, for example, about 1200.

The length of the rack 11 is calculated so that, when the pressure-rod 14 comes to the end of its stroke, in the position shown in Fig. 4, the segment 10 will have moved through exactly one-half of a revolution. At that point, the toothed portion of the segment 10 is out of mesh with rack 11 and is in position to mesh with rack 12.

At this stage, pressure on the button 15 is removed and the spring 17 acts, in the direction of the arrow R (Fig. 5), to bring back the block 13 and racks 11 and 12 to rest as in Fig. 2. As may be seen in Fig. 5, segment 10 is turned by rack 12 as the block

13 returns to the position of Fig. 2 under the influence of the spring 17. The length of the rack 12 is also calculated so that segment 10 shall have moved one half of a revolution when block 13 comes to rest. Segment 10, over the whole cycle, has thus made one complete revolution and is now back exactly to its starting-point, that is it is ready to mesh with rack 11 for another cycle.

In rotating, segment 10 takes with it the shaft 2 of the meter, and the return to zero is thus brought about since the shaft 2 will have made a complete revolution.

To summarise the operation of the device it will be seen that during the forward stroke of the control button 15, when pushed by the operator, the toothed segment meshes with one of the racks and moves through 1800, then, during the return-stroke of the control under the action of the spring, the toothed segment meshes with the other rack and again moves through 1800. One forward and return stroke thus corresponds to one complete revolution of the toothed segment and thus, of the shaft of the meter.

Thus a device according to the invention is much more compact that known devices, since the racks serve to move the toothed segment through 1800 and are thus much shorter than the single rack of current devices.

WHAT WE CLAIM IS: 1. A device for resetting a numbered drum register of the kind comprising rotary drums graduated from 0 to 9, set side by side, and fitted onto a common shaft which remains. fixed while the drums rotate, but

which, when turned through one revolution in a given direction, moves the drums in such a way as to align their zero-graduations with a set mark, characterised in that the device comprises a toothed-segment keyed onto said shaft and having teeth over an arc of less than 1800, two racks of generally identical design set symmetrically on either side of said shaft and secured to a single control, the racks and the control being guided in their movement in a fixed bearer, said control being movable between two stops defining start and end-of-stroke positions respectively, and being biased towards said start position by a spring, the segment and the racks being designed and arranged such that the segment is only ever meshed with one of the racks and that the toothed segment, when the control is in either of said position is positioned to mesh with one of the racks.