DE2226319A1 - DIGITAL OPERATING AND DISPLAY DEVICE FOR MULTIPLE, AXLE-OPERATED PRECISION POTENTIOMETERS AND ADJUSTABLE INSTRUMENTS - Google Patents

Description

"Digital operating and display device for 2226319 multi-turn, axis-driven precision potentiometers and adjustable instruments "

Attempts have repeatedly been made to create button-like devices for potentiometers, which through a cutout in a front panel or a dashboard protrude forward and on the one hand a control button for turning the potentiometer axis and on the other hand a display device to display the number of full revolutions and the fractions one full turn of the potentiometer shaft. Examples of previously known devices for operation and display are for example in U.S. Patents No. 2,777,637, 3,067,935, 3,202,127, 2,980,055, 2,805,636, 3,183,885, 3,241,515 and 3.4-50,091. Such devices are usually either counted among the class of display devices with multiple scales, or to the class of devices with digital numeric display. The first three of the above-mentioned patents relate to the latter class, while the other patents relate to devices with dials.

Dialed indicators require considerable amounts Mounting space if the scales have the total length required for high reading accuracy. In embodiments with gears, the wear of the gearing has an effect detrimental to the service life of the device. In addition, the operator must dismiss devices with display dials. Add read ads to get the correct total display which increases the risk of reading errors.

In known digital display devices, sets of number wheels are used as in the case of an odometer, wherein gears establish a connection between the hand-operated control button and the first number wheel of the set. Since the first two indicating number wheels show decimal fractions of a single full turn of the potentiometer axis should and because the third number wheel should display full revolutions up to a maximum value of ten revolutions

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usually the first number wheel rotated ten full revolutions during each full revolution of the axis, with the first number wheel turns the second one decimal place for each revolution of the first number wheel. In a similar way The second number wheel rotates the third one by one step or one decimal place with each revolution, i.e. with each full turn of the control knob or with connected to it and driving the potentiometer. A 10: 1 gear ratio is commonly used between the button and the first number wheel introduced. The pinion for the first number wheel is significantly smaller than the control button and turns very quickly when it is turned. Since the first number wheel is turned ten times as fast as the button, step on incremental tooth of the second digit wheel on high shock loads if the same by one decimal place in forwards or Reverse direction is advanced. The wear of the pinion assigned to the first number wheel is therefore significant higher than that of the other gears, and this pinion is therefore usually made of metal instead of the less expensive thermoplastics that are otherwise used for other gears. The only pair of teeth on the first number wheel, hereinafter referred to as the progressive pair of teeth, and that at the end of each revolution advances a corresponding tooth on the pinion mounted between the first and second number wheels by one position, hits the pinion tooth at a speed

ρ
V, where energy proportional to KMV is transmitted to the pinion as a shock. Here, K means a dimensionless constant and M a constant corresponding to the mass. The impact energy depends on the square of the speed of rotation of the first number wheel and thus on the speed of rotation of the potentiometer's adjusting knob.

Known digital operating and display devices

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are therefore relatively large, expensive to manufacture, or wear out quickly or exhibit a combination of these adverse properties.

The present invention overcomes or significantly reduces these disadvantages. Wear and tear is in accordance with the invention of the pinion assigned to the first number wheel by half

2
reduced and the energy transfer corresponding to the product KMV

load is reduced by about three quarters to KM (F / Z) by adding two sets of ratchet teeth to the first number wheel the gear ratio between the drive knob and the first number wheel is reduced to 5: 1, and the sequence of digits on the first digit wheel is reduced to two sets of decimal numbers with the digits 0, 2, 4, 6 and 8. The 5 s1 ratio, which replaces the 10: 1 ratio used in known devices, reduces the number of revolutions of the first number wheel per full turn of the operating button s to five and thus reduces the wear and tear of the Pinion of the first number wheel and its speed of rotation to half, whereby the impact energy to be absorbed by the pinions or the indexing teeth is reduced to a quarter reduced. The reduced load makes it possible to use the thermoplastic pinion associated with the first number wheel To manufacture plastic in one piece with the number wheel, thereby increasing the total cost of the number wheel unit displaying the first number reduce significantly and eliminate the cost of assembling the pinion and the number wheel at all.

The advantages are referred to in detail in the following description of an exemplary embodiment explained on the figures.

Figure 1 is a perspective view, not to scale, of the drive shaft of a faceplate mounted Precision potentiometer and sets the rotatable operating and display device removed from the axle.

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Figure 2 is an enlarged partial cross-sectional view of the apparatus shown in Figure 1 and shows one Form of attachment of the potentiometer on a front panel and the attachment of the device according to the invention to the potentiometer axis .

Figure 3 is a cross-sectional view of a portion of the apparatus shown in Figure 2, but the cross-section is "im right angle to the cross section of Figure 2 and shows the arrangement of the button-like actuating device, the number wheels and the transmission.

FIGS. 4 and 5 are cross-sections along the lines shown in FIG lines marked with 4-4 and 5-5 respectively.

Figure 6 is a partial view of a portion taken along the line designated 6-6 in Figure 2.

Figures 7, 8, 9 and 10 are cross-sections of the number wheels and gears of the display mechanism shown in Figures 1, 2 and 3; the cross-sections being taken along lines 7-7 and 8-8 and 10-10 of Figure 3 and Figure 8 parts in represents a position different from Figure 10.

FIG. 11 is a perspective view of an indexing sprocket of the display device illustrated in FIGS. 1, 2 and 3.

Finally, FIG. 12 is a schematic view of the number sequences attached to the circumference of the three number wheels.

The device according to the invention can be mounted on a rotatable operating axis S (FIG. 2) on a front panel Precision potentiometer I are attached, in the example shown at an opening A in the front panel P is fastened by means of a socket B with an external thread and an associated lock nut N. The S axis for potentiometer adjustment is rotatably mounted in the socket.

According to the invention, a mounting washer 20 is on the front panel P fastened by means of the lock nut Ν, with one as

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Washer acting spring washer W can be used. Mounting disc 20 is perforated to provide a locking extension To create 20t that fits into a hole H in front panel P. This means that the mounting washer cannot be on the Twist the bushing. The socket has the overall shape of a bent one Washer and is provided in the manner shown in Figure 1 with two outer extensions 20k. The operating and Display device comprises a fixed, internally toothed Gear 22, the rear flange surface 22f of which is interrupted by two depressions 22r (FIG. 6) into which the Projections 20k of the mounting disk 20 protrude. On its front side, the internally toothed gear 22 is annular with a arranged row of internal teeth 22t (Figure 2). An annular bearing surface is located between the end surfaces 22b, which in turn rests on an annular holder or a carrier part.

The operating and display device also includes a rotatable cage for an epicyclic gear, which is referred to below as a circulating carrier 24 (FIGS. 2 and 4). The circulating beam consists of an inner metal sleeve 24s to which the body of the circulating beam is permanently attached by corrugation or knurling. Metal sleeve 24s is drilled out to receive an adjusting screw 24c, which establishes a connection with axis S in the screwed-in state (FIG. 2). The carrier of the epicyclic gear can thus transmit a torque to axis S in order to turn the same to adjust the precision potentiometer I. A rear, cylindrical bushing section of the rotating support is provided with an outside bearing surface which is a counterpart to the bearing surface 22b of the stationary toothed gear 22 and can rotate in the latter layer. precede his Uinf-inr with a groove, in dor ο in C-shaped, fi L ■ s 3 ti so ha ν Ha "! te rim: 2 \ v öinlio.-t and dm lnnenver-

■ ί ο η v, 2 a / ο 3: »R

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toothed gear 22 on the rotating carrier.

Circulating carrier 24 is provided in the longitudinal direction with three bores 24h (FIGS. 2, 4 and 5) in which double-sided Planetary gears are stored. The opposing sets of teeth of these gears are expediently of the same type educated. The teeth at the rear ends complement each other with the teeth 22t of the stationary, internally toothed gear 22, As can be seen from Figure 1, the circulating carrier has an im substantially cylindrical outer surface, which is the rear part of a longer cylindrical surface, the in turn can be rotated to rotate the axis S by applying a torque. An extension of the surface results from an internally stepped cylinder shell 28, the arrangement of which is shown in FIG. 2 and its front side End of the transparent lens 30 is formed. Cylinder shell 28 encloses the display mechanism of the invention Device and can according to the display device be attached to the circulating carrier at an annular, stepped connecting part 28j (Figure 2). the Connection results from two cooperating radial surfaces and a pair of cooperating cylindrical surfaces, the fit together exactly and can be joined together by a binding agent or by ultrasound to form a part comprising the circulating beam and the cylinder shell,

The digital display device comprises a circular holder 32 (Figures 2 and 3) with an inside row of teeth 32g which are in engagement with the front teeth of the epicyclic gear and at the same time a cylindrical Form bearing surface 32b, which represents the counterpart to the inner cylindrical bearing surface of the cylinder bowl 28. Cylinder shell 28 and the associated extension formed by the circulating carrier can thus on the

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rotate cylindrical bearing surface 32b. When rotating the cylinder shell 28 and the rotating carrier to adjust the precision potentiometer I, the rotating gears 26 are carried along and as a result of the engagement of the rear row of teeth in the teeth of the stationary, internally toothed gear 22, the rotating gears are set in rotation about their axes. When the cylinder shell is rotated, the rotation of the small planetary gears about their axes results in a relative movement of the circular holder 22 counter to the direction of rotation of the cylinder shell 28. The holder 32 remains stationary with respect to the front panel P, while the S axis passes through the cylinder ^; chale and the carrier of the epicyclic gear is set in rotation. The circular holder 32 is used to support the rotatable parts contained in the rotating cylinder shell behind the lens 30 for revolution counting and digital display.

The two support pillars 32p attached to bracket 32 and protruding forwards provide two saddle points 32s and 32s' (Figure 3) for receiving the hub 32h of the first number wheel 38 and an axle 34. A circular frame 36 (Figure 2) is mounted on the front ends of the bearing pillars 32p and with a window 36w (Figure 1), behind which the numeric display appears. The frame is. on bracket 32 expediently with pins 32a (Figure 2) attached to the Bearing pillars are attached and fit into corresponding holes in frame 36 and connect without the use of binders result. Other suitable means of securing the frame and window can be used.

At one end of the axis-34 (Figure 3) is the one with the Number wheel 38 one-piece pinion 38p mounted, hub 38h and the pinion sections of the number wheel 38 lie in the saddle point 32s. The end of the axle applied to the pinion 38p 34 sits accordingly in the saddle point 32s', so that overall.

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a bilateral mounting of the axle is guaranteed. Number wheel 38 can thus rotate with the axis.

Pinion 38p of the first number wheel engages mating teeth 28g (FIGS. 2 and 3) of the rearward-facing set of teeth on the inner surface of the cylindrical shell 28. Rotation of the cylinder shell 28 thus results in a rotation of the pinion 38p and the number wheel 38. In contrast to previously known counting devices, the ratio of the number of teeth 28g to the number of teeth on the pinion 38p is 5: 1 instead of the ^v commonly used, for example in U.S. Patent No. 2,777,637 described 10: 1 ratio. The first number wheel thus only rotates five revolutions for each revolution of the cylinder shell 28 and the axis S. In the case of precision potentiometers, the first number wheel is usually used to display the hundredths of a full revolution of the axis, while the second number wheel is tenths of a revolution and the third show full revolutions of the potentiometer axis. In certain applications, additional number wheels, for example a fourth number wheel, are used. Since in the present invention the ratio of the number of revolutions of the axis S to the number of revolutions of the number wheel 38 is 5: 1, so that number wheel 38 performs five revolutions per full revolution of the axis S, every half revolution of the first number wheel corresponds to ten hundredths of a full one Revolution of the axis S. The numbers attached to the number wheel 38 thus indicate ten hundredths of an axis revolution on each half of the outer circumferential surface of the number wheel. The corresponding sequence of digits is given in the right-hand column of FIG. 12, the sequence of digits being 2-4-6-8-0-2-4-6-8-0 and thus running through the series of decimal numbers from zero to ten twice. To make it easier to read the device with its small diameter, the odd numbers are the

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The series of decimal numbers is omitted or by slashes in the manner shown in Figure 12 replaced.

As shown in Figure 1, a reading line L is provided on the front of the frame 36 in the center of the window 36w. The slashes and decimal numbers on the number wheel j> 3 can be brought into line with this reading line. Further division lines indicate hundredths of an axis revolution and thus increase the accuracy of the display obtained with the first number wheel.

Since every half revolution of the first number wheel 38 corresponds to a tenth of a revolution of the axis S, means are for two increments of the second number wheel 40 provided during each full revolution of the first number wheel.

As mentioned, the display device comprises three number wheels with decimal numbers, namely the first number wheel 38, the second number wheel 40, and a third number wheel 42 (Figure 3). The last two number wheels are ring-shaped and have cylindrical outer scales and inner surfaces with an endless set of teeth. Numeral wheels 40 and 42 surround a hollow carrier roller 44 (Figure 3), the interrupted cylinder surface represents a storage area on which the number wheels are arranged side by side in a known manner. Bore 44b at the inner flange end of the carrier roller is used for receiving one end of the axle 34, which thus represents a holder for the carrier "roller. The carrier roller is provided with bores for receiving it an axle 46 on which a first indexing pinion 48 and a similar second indexing pinion 50 are stored (Figure M). Progressive pinion 48 consists of a drive section 48a having six teeth and an input section 48b with also six teeth, which alternately shorten b and are provided with tooth surfaces 48c and 48d (FIG. 8). I) Reading tooth surfaces are designed in such a way that they are

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Broehenen circular, inner flange surface of the associated number wheel (for example surface 38f, Figure 8) in engagement can come and thereby block the rotation of the indexing pinion, unless the input section of a corresponding tooth meshes with the corresponding inside gear formation on a preceding, i.e. driving number wheel (for example bulge 38d of the Number wheel 38 in Figure 9). The ends of the cooperating Teeth are shortened or omitted (Figure 11) to create a gap for the inwardly extending flange portion with reduced diameter on the number wheel. Examples of this arrangement are flange 38f of number wheel 38 (Figure 8) or a similar flange of the number wheel 40 in Figure 10. These flanges have interruptions 38i and 40i, respectively, around the Rotation of the indexing pinions 48, 50 when they are driven to enable corresponding gear sections.

The first number wheel 38 is in the manner shown in Figure 9 with a pair of opposite bulges trained drive teeth 38d provided. The space between the two teeth of the bulge is in each Case aligned with an associated interruption 38i (Figure 8), so that when the tooth arrangement 38d engages in the Driven tooth sections of the indexing pinion, the locking section of the tooth on gearwheel 48 can be rotated further can (Figures 8 and 10). When the first indexing pinion 48 moves one step, i.e. two teeth, through the driving Tooth sections on the first number wheel is rotated, the driving tooth section of the B'ortsohal pinion switches the Second number wheel by a tenth of a revolution further, since 20 teeth of the type of the tooth shown in Figure 9 40t nm Inside, driven end of the number wheel 40 provided üind.

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When turning the cylinder shell 28 and rotary carrier 24 • comprehensive button for further turning the axis S of the precision potentiometer I rotates the internally toothed gear 28g in the cylinder shell 28, the port switching pinion 38p of the first number wheel 38 continues at a rotational speed that is five times as great is than that of the S axis. The number wheel 38 offers two consecutive poles of decimal numbers during each revolution of the number wheel of the operator's observation, i.e. during each full revolution of the axis S, the Decimal numbers from zero to nine displayed ten times. The first number wheel shows the hundredths of the revolutions of the Axis S on. Additional lines between the digits on the number wheel (Figure 12) denote fractions a hundredth of a revolution of the S axis and can be read on the window 36w. Every half turn of the number wheel corresponds to ten hundredths of a revolution of the axis S. Since, furthermore, the second number wheel 4-0 corresponds to one, two teeth The distance (one tenth of a turn) is incremented every time the first number wheel makes half a turn, the second number wheel indicates tenths of a full revolution of the S axis.

The second number wheel 40 has, as shown in Figure 10, a single indentation serving for the drive and therefore rotates the second indexing pinion 50 by two Teeth corresponding distance with each revolution of the number wheel 40 further. This will turn the third number wheel by one distance corresponding to two teeth or one tenth of a revolution for each full revolution of the number wheel 40. The third number wheel is rotated one full turn for every ten revolutions of the second number wheel and ten revolutions of the S axis. If number wheels 38, 40 and 42 have decimal numbers in the one shown in FIG Way, shows the third number wheel

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at the window 36w the number of full revolutions of the axis S starting from an initial or zero position, while the second number wheel 40 is simultaneously the tenth of a full Rotation of the axis S from a zero position or from a completed revolution, and the first number wheel indicates the Hundredths or fractions of a hundredth of a revolution of the S axis, calculated from every completed tenth of a revolution, indicates.

Since the first indexing pinion 38p executes only five revolutions for each revolution of the axis S, there is wear of the pinion compared to that of a corresponding pinion in a 10: 1 reduction in known digital display devices reduced by half. That to switch required torque is also reduced by half. There is also the speed at which the driving teeth of the gear act on the driven teeth when switching, also reduced by half in comparison to known devices, is the shock load occurring on the driven teeth when a number wheel is advanced reduced to about a quarter of the value of the shock load occurring in known devices. The present The invention thus results in a significant reduction in part wear and increases the service life of the device. The likelihood of damaging or blocking the Parts in the gearbox of the display device are also significantly reduced. As the number of teeth in the indexing pinion of the first number wheel is doubled compared to the number of teeth in known devices, is the diameter of the The indexing pinion 38p is doubled and pinion teeth with larger dimensions and increased mechanical strength can then be used with a button gear less than 2.5 cm in diameter be used. This point is of particular importance

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when using buttons less than an inch in diameter should be to accommodate enough control buttons in a small space in an instrument. In the case of buttons with a diameter of 2 cm, the 10: 1 ratio of known devices requires expensive gears and first indexing pinions Metal. Even in the case of known, button housed gears with a diameter of about 3.8 cm or more In known arrangements, the indexing pinion assigned to the first number wheel is made of metal so as not to go through the forces occurring when switching to be broken and not to wear out too quickly. As described in U.S. Patent No. 2,777,637, in this case two or three parts were used to build the first number wheel and the associated one Pinion necessary, which on the other hand complicated the assembly of the "device. In contrast, in the case of the invention Device the first number wheel, its hub and the associated pinion in one piece from a self-lubricating or low-friction thermoplastic material. The invention thus enables production of operating and display devices of significantly reduced diameter with a simultaneous reduction in manufacturing costs and increasing the life of the device. The invention thus enables the aforementioned aims to realize.

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Claims (4)

PATENT CLAIMS Operating and rotation display device for multi-turn potentiometers and setting instruments, marked by a first rotatable section (24) for coupling to an adjustable section of the potentiometer (i) or setting instrument, with an outer cylindrical surface (28) that can be rotated by manually exerting a torque Adjustment of the potentiometer (I) or adjustment tool; an internal gear included in the first rotatable portion (24) (internally toothed gear 22t) with an axis for transmitting the torque to the display device and one with the Axis coaxial, inner bearing surface (22b); a second section with a display device consisting of a holder (32) and a pinion (38p) attached to the same, which is connected to the internal gear of the first rotatable section (24) is engaged; at least a first and a second number wheel (38, 48) in the display device and interconnected Indexing pinions (40, 42), which are driven by the torque applied to the drive pinion as the rotatable Section are operated, the first number wheel (38) and the drive pinion (38p) connected directly to one another and the gear ratio between the first gear and the pinion is 5: 1, so that the pinion at each full revolution of the first driving gear makes five revolutions; first and second diametrically opposed Indentations (38d) on the first number wheel, which the indexing gear twice for each revolution of the first number wheel (38) actuate, the second number wheel (48) is rotated further by one tenth of a revolution; and means that hold the holder stationary during the rotation of the rotatable section about the axis (S). 2. Device according to claim 1, characterized in that 303829/0336 / 5 that the first number wheel (38) is provided with rows of decimal numbers from zero to nine on each half of its outer circumference is to the rotation of the rotatable portion (24) by a tenth 1 revolution for every half revolution of the first number wheel (38) to display. 3. Apparatus according to claim 1, characterized by stationary gear means (internally toothed gear 22t), which against Rotation around the axis are locked, as well as by a set of rotating around the axis, mounted in the rotatable section Epicyclic gears (26) of a planetary gear, which when rotating rotating the rotatable portion (24) about its axes in the stationary gear (22t); and one in mesh with the epicyclic gear stationary gear that holds the bracket (36) stationary in relation to the rotation of the rotatable section (24) on the stationary gear (.22t). 4. Apparatus according to claim 1, characterized by a rotatable, protruding through an opening in the mounting plate Axis (S) on which the rotatable section (24) can be attached to cover the axis from the outside, the axis of rotation of the first driving gear (26) coaxial with the axis (S) appears arranged and the bracket in reference to the Mounting plate (P) remains stationary. 309829/0335