DE662892C - Adjustment device for transferring the deflections of measuring instruments, in particular automatic scales, to a display or printing device - Google Patents

Description

Adjustment device for the transmission of deflections of measuring instruments, in particular from automatic scales to a display or printing device Im The main patent is a display or printing device for scales described in which the speed of the tracking device shortly before reaching the Balance setting is decreased corresponding to the setting. Controlling the Tracking device is used among other embodiments with the help of electrical Contacts causes. These contacts act on the moving parts of the scale - albeit weak - forces exerted, which in particularly sensitive scales or other measuring instruments. affect the free movement of the same. According to of the invention are used to control the trailing speed reducing Device as well as the locking device connected to this control elements are used, by which such forces in a known manner from the adjuster to the scales not be transmitted.

The invention is on the drawings in several embodiments illustrated schematically. To simplify the illustration, there are several Gear parts shown rotated in the plane of the drawing. With the scales according to Fig. i denotes t the balance pointer, 2 the adjuster known per se, which from Balance pointer is stored independently in its geometric axis. On this adjuster a reset weight 3 (or spring) is attached. The display device 4 is a circulation counter connected to shaft 5. 6 is an electric motor whose Transfer movement through the shaft 5 to the adjusting member and the display device will. The balance pointer i has an extension designed as an electrical contact 7 provided. A solenoid io is attached to the top of the adjusting member 2, in its sleeve an arm i i as an extension .des adjusting member is arranged so that it is through a spring is held in the position shown. Located on this arm i i a contact 8, which is used to operate the lock 9, and the contact i2, the with contact 7 the reduction of the follow-up speed shortly before reaching the Pointer turns on via the shift gear 13. In the unexcited state of the magnet io the contacts 8 and 12 are in the raised position so that they with their mating contacts i and 7 are not in contact. 1d. is an electromagnet, which, when excited, arrests the balance pointer i only so lightly that the Pointer due to the small drag resistance when making contact between 7 and 12 does not move. In the circuit of the lock there is still a relay 15 that when excited, releases a stamp 16 for printing the set weight. 17 is a contact which, when actuated, connects the entire electrical installation the network is switched. 18 is a contact that opens when the lock 9 is excited will. To prevent the lock 9 from falling off when the contacts 1, 8 are loosened this has a self-holding contact 18 ', via which it continues until it is tripped of switch 17 receives voltage. However, the arrangement of the self-holding contact is not the subject of the invention.

The mode of operation of the balance is as follows: When the balance is used has, the contact 17 is closed by a handle, thereby the following Circuits switched on: positive wire via contact 18, magnets 1 ¢ and io to negative wire continue from the plus line via the contact i 8, electric motor 6 to the minus line. The magnet 1,4 attracts, locks the pointer i slightly in its position, through Solenoid io, arm i i is pulled into its coil and contacts 8 and 12 in brought the area of their mating contacts i and 7. At the same time, the engine 6 is running and moves the trailer 2 to your balance pointer. If the follower is the pointer i has passed on in such a way that contact is made at 7 and 12, the electromagnetic changeover gear 13 the speed of the further follow-up movement reduced until the lock 9 in action by contact closure between i and 8 occurs, which holds the display device for printing. At the same time is at Triggering of the lock 9 of the circuit of the magnets io and 1: I interrupted at 18, the magnets are excited and the pointer is completely released from both magnets and not hindered in its further movement. However, the weight remains until Opening of the contact 17 is set via contact 18 'and can be activated by the stamp 16 can be printed. When the contact 17 is opened, the lock 9 is de-energized and the entire device by .das reset weight 3 returned to the zero position.

In Figure 2, an embodiment of the balance is shown in which on the pointer shaft is a spiral disk i with a (lein deflection proportional Slope is attached. The back-up 2 is designed here as a toothed rack, one end of which is provided with sleeve-like bearings similar to FIG. in which there is an arm i i (shown rotated by 90 ° in the drawing), on which the contacts 8 and 12 are mounted isolated from one another. ro is a Electromagnet which, when energized, moves the contact arm i i perpendicular to the plane of the Disk i moved in the direction of the arrow, so that the contacts 8 and 12 in the plane of the spiral disk i are brought. In the de-excited state of the magnet io the contacts 8 and 12 are not in the plane of the disk i and are with the disk i not in contact, so that the latter can move freely.

The operation of the device is as follows: Under the effect the load rotates the disk i in the direction of arrow a. As a result, the contact 8 a smaller polar radius of the spiral is set. With enough big The deflection, the decrease in the polar radius will be so great that contact i2 will also be outside of the area of the disc. When the balance has run in, as shown in Fig. i described, the magnet i o energizes and moves the contacts 8 and 12 into the plane the disk i. The motor starts up and moves the rack 2 in via the shaft 5 Direction of arrow b. If now the contact 12 with the edge of the disk i, the positive voltage leads, comes into contact, is a circuit for reducing the follow-up speed closed and the rack 2 slowly moves on. Because the direction of movement of the contact 12 directed in the radial direction towards the pivot point of the disk i- the position of the disc is not influenced by the contact friction. If now the contact 8 reaches the edge of the disc i, the lock 9 is activated via it set, which blocks the further follow-up movement, and, as described in Fig. i, Magnet io de-energized and contacts 1, 8, 12 out of contact.

In Fig. 3 is a balance with one controlled by liquid contacts Follower shown. The parts d., 5, 6, 9, which correspond to those of the execution correspond to Fig. i, also bear the same numbers here.

The incline weight i9 is fixed with arm 20 and your circle segment 2i tied together. A steel band is attached to this segment, on which the load Q attacks. Does the segment ai have a circular border with the center in Fulcrum 22, then, as is known, the sine of the deflection angle of the balance is proportional the load Q. 23 to 26 are grid-like contacts, the serve to control the follow-up movement. They are on a common carrier rigidly attached; the latter stands with the arm -2o and with the arm around the fixed pivot point 28 rotatable arm 29 in an articulated connection. The arm 29 causes parallel guidance of the contact carrier, so that it turns to itself at any deflection of the balance is guided in parallel. In this way there is a deflection under the load O the contact finger, whose perpendicular component is proportional to the sine of the Deflection angle and thus also proportional to the size of the load O itself.

The contact fingers 23 to 26 dip into vessels 3o to 33, which are up to contain mercury or some other conductive liquid at a certain level, which is covered with a protective liquid. 34 is a reserve space for the protective liquid, which is connected to the contact vessels via the holes 35. The usage the protective liquid is not the subject of the invention.

The vessels 3o to 33 are made in a manner similar to the contact carrier guided in parallel. 36 is a two-speed electromagnetically operated transmission gear, the triggering of which is controlled by the contact finger 23.

The contact vessels 3o to 33 are isolated from one another and each with one Provided power supply, while the contact fingers 23 to 26 isolated on their carrier attached, but are conductively connected to each other.

In the drawing, the balance is shown in the zero position. Here the contact 25, which supplies the positive voltage to the other contacts, and the contact 23, which controls the reduction of the follow-up speed via transmission gears 36, are immersed in their vessels; the end of the contact 24 just dips into the mercury so that current can flow via the line 37, the vessel 32, the fingers 25 and 2.4, the vessel 31, via the line 38, magnet 9 and line 39. In this position, the magnet 9 is attracted and the power supply to motor 6 is interrupted at 1 8.

The function of the balance is as follows: When a load is placed on the balance, the inclination weight r9 deflects in the direction of the arrow, and consequently the contact 24 first leaves its counter-contact. Immediately the contacts 23 and 25 also leave their mating contacts, with the exception of the case in which only a very small load has been placed on the scales. The current through the magnetic lock g is now interrupted, and this releases the follower and switches on all of your contacts I8 the 'motor (.-). The follower is thus set in motion, namely, since the coil 4o is not carrying any current, in high gear. As soon as the follower has come so far in its movement that the contacts 25 and 23, which are approximately the same length, are immersed, the coil 4o receives power via the line 37, the contacts 322, -25, 23, 30 and line 41 and shifts the transmission 36 to slow gear. During the further tracking, the contact 24 comes into contact with the mercury in the vessel 3 r, the magnet 9 attracts and immediately detects the follower, with the feed line to the motor 6 being interrupted at the same time by contact 18. As a rule, the disconnection and determination of the follower will take place sufficiently quickly so that the determined position of the display device 4 will correspond to the scale deflection, especially since the movement of the follower has already been delayed by the changeover gear 36.

Regardless of this, a safety device is provided in the fourth contact finger 26 and the corresponding mercury vessel 33, which gives the follower a backward movement if the latter should have run out of its correct position when it is detected. Contact 26 is only very slightly shorter than the locking contact 24, and at most by so much that it makes contact as soon as the follower has run too far by exactly one unit of the setting wheels. In this case, the coils 9 and 40 and the motor 6 are short-circuited by the contact 26 via resistor 42, line 37, the contacts 32, 25, 26, 33 and line 43. On the trailer, which has now become freely movable due to the falling magnet 9, only the spring 4.- now engages. which seeks to pull it back into its rest position until the tip of 26 comes out of contact again, the magnet 9 attracts again and the trailer is now in the correct position. In order to prevent an excessively large current from occurring at the contact 26, a resistor 42 is switched on in the lead 37. After weighing, the decrease in the load on the balance causes the contact carrier to approach the mercury containers again, contact 26 now initiates the return movement of the follower in the same way as before, which returns to the rest position.

In Fig. 4. the circuit diagram of the same balance is shown in which to increase the service life of the contacts, they are no longer used for immediate switching of the motor or the coil currents are used, but indirectly via a Amplifier by namely via the grid-controlled rectifier 45 work.

The armature of the drive motor 6, the coil of the locking magnet 9 as well as the coil of a relay 46 are in the anode circuit of a rectifier 45 switched, which is fed from the AC power source 47 and in a known manner is controlled by applying various voltages to the grid 48. As a drive motor 6 a separately excited DC motor is used here, its field coil in the circuit diagram is not drawn. The control voltages are first an autotransformer 49, which is provided with two taps 5o and 51, secondly the auxiliary direct current source 52 (for example from an accumulator battery). 53 and 54 are ohmic resistances, 55 and 56 are impedances. 57 is a block condenser; 58 is a choke coil; both serve to keep AC power away from battery 52.

As is known, the grid-controlled rectifier 4.5 has the property of passing current in the direction from the anode 59 to the cathode 6o as long as the voltage at the grid 48 is positive with respect to the cathode; on the other hand, a low grid voltage prevents the discharge from igniting and thus the passage of current. A gas-filled rectifier is intended, which is suitable for allowing larger currents to pass through. If such a rectifier is fed with alternating voltage and an alternating voltage of a suitable level and phase is also applied to its grid, the ignition point can be shifted to any part of the period, i.e. the current flowing through the rectifier to any values, possibly up to o throttle. The control voltages generated one after the other on the grid when the contact fingers 23, 26 are immersed in succession should be approximately as follows: When the carrier 27 approaches the vessels 30 to 33, as in the embodiment according to FIG. 3, the fingers 23, 25 should first immerse. As long as none of the contacts is immersed, the grid 48 is only connected to the cathode 6o via the bleeder resistor 53. The rectifier therefore lets through the full half cycle, and the current flowing in the anode circuit under the action of the voltage of the current source 47 assumes approximately the value 1 as a result of the resistances present in the anode circuit. The amperage - I should give the motor 6 its full torque, so that the follower is moved in high gear as long as none of the contacts is immersed. Now dip .the contacts 23, 25 in the cups 3o and 32, then the grid 48 from the tap 5o of the auxiliary transformer 49 via the impedance 56 is supplied with an alternating voltage whose phase and size are such that only through the rectifier a significantly smaller stream, e.g. B. about i / 15 of 1, is passed. This also reduces the torque of the motor to around the 15th part, so the speed of the movement of the follower is initially significantly reduced. When the contact 24 is immersed, it applies the negative DC voltage of the battery 52 to the control grid 48 and at the same time creates a bypass path via the blocking capacitor 57 for the auxiliary AC voltage that has remained connected via 23, 25. The rectifier is thus completely blocked for the passage of current, the motor armature and the magnets 9 and 46 have become de-energized. In contrast to the previous one, the locking magnet 9 is arranged in this embodiment in such a way that it releases the trailer when it is attracted and locks the trailer when it is released. So it is adjusted in such a way that it picks up at about 1/10 of the full current strength. The magnet 46, which is adjusted in such a way that it attracts at about '/. " The fourth contact 26 is used here, as in the previous embodiment, to return the follower. For this purpose, contact 26 leads from the tap 51 of the auxiliary transformer 49 via the impedance 55 to the grid 48 an alternating voltage again and at the same time creates a bypass path to divert the reverse direct voltage in such a way that the rectifier 45 in this state just passes enough current through again - about '/ so from I - that the locking magnet 9 releases the follower, the However, magnet 4.6 does not yet attract, that is, it continues to short-circuit the motor armature 6. The spring 44 can therefore now move the trailer back in accordance with the embodiment according to FIG.

In the scales according to FIGS. 5, 6 and 7, the follow-up movement of the balance is influenced by electrostatic effects in such a way that none or only negligibly small mechanical repercussions on the balance arise. The parts 1, 2, 3, 4, 5, 6, 9, 18, 36, 4o known from the previous statements receive the same numbers here as well.

In Fig. 5, an embodiment is schematically shown, in which a variable capacitor is drawn, its one assignment 61 on a movable part of the balance, for example on the pointer i of the same, and its other Occupancy 62 on a rotatable part 2 of the trailer that is coaxial with the pointer i is appropriate. The capacitance value of the capacitor formed from the assignments 61 and 62 thus depends on the mutual position of part i to part: 2, namely is it is advisable to choose the form of the assignments so that the dependency is clear will. It goes without saying that the assignments can also be given other shapes can than those shown in FIG. 5, in particular one can have several layers of assignments next to each other, which then roughly comb-like without mutual Intertwine touch in case one deals with the small capacitance value of a single occupancy pair does not want to be satisfied. The capacitor 61, 62 is in the Lattice circuit of an amplifier tube 63 switched on, the anode current via the electromagnet 9 and influences the excitation of the drive motor 6 via the coil x. As a drive motor 6 a DC motor with two excitation windings is used here, namely the winding x acts through which an anode current i ″ of the amplifier tube flows is opposite to the shunt excitation winding y. With 66 are here, as in Figs. 6 and 7, the anode power sources indicated.

On the grid of the amplifier tube 63 is next to the grid discharge resistor 6d. an alternating current source 65 connected as constant as possible, but so that the a supply line to the voltage source 65 is interrupted by the capacitor 61 to 62 so that the grid voltage of the tube becomes a function of the capacitance value, thus dependent on the mutual position of the assignments 61 and 62 and thus of the angular deflection a between parts i and 2.

So there is also the current i "in the anode circuit of the amplifier 63 be a function of the angular deflection of parts 1, 2 with respect to one another.

In the form of the assignments indicated in FIG. B. the The anode current i "decrease evenly when the angular deflection a decreases. The weakening of the field cles motor 6 through the coil x gradually disappears when the Angle a between parts 1, 2 becomes smaller. This is the speed of the engine reduced and thus causes the reduction in the follow-up speed.

If the angle x between the parts i, 2 is equal to o, the Anode current i "has a very specific value ial. The locking magnet 9 is now like this adjusted so that it attracts its anchor and thus the previously with reduced Detects the speed of the moving trailer. A pair of contacts 18 switches at the same time the motor 6 from the mains. In addition, the mode of operation of the balance be as described in the main patent. In particular, the provision of the trailer after. carried out weighing and registration by the indicated with 3 Draw weight. The reset can .aber also in other ways, for example by the motor itself, which is then reversed with the help of a reversing switch The senses are set in motion. The reverse switch can be used operate in a similar way to the magnets with the help of amplifier tubes, which either come from the same capacitor assignments 61, 62 or from special, further assignments provided for this purpose can be controlled. In the Fig. 5 is a particularly simple circuit used, but not the only one possible. In particular, because the setting accuracy depends on the precise work of the locking magnet 9 depends on the most, prefer circuits that absolutely ensure this, even if they are less simple.

In Fig. 6, the variable capacitor 61, 62, which is indicated here schematically, forms a branch of a bridge, which is composed in a known manner from ohmic resistances and impedances 67 to 69 and balanced in such a way that the voltage across the bridge resistor 67, which at the same time is the grid leakage resistance of the amplifier tube 63, then disappears when the capacitance of the capacitor 61, 62 assumes the value corresponding to the angle a = o. The locking magnet 9 is traversed by the anode current of the tube 6.3 and detects the follower when this current disappears. This circuit has the particular advantage that the magnet 9 does not have to be precisely adjusted to a specific current value and that fluctuations in the voltage of the auxiliary power source 65 do not affect the triggering accuracy if only the magnet 9 is sufficiently sensitive and the amplification on the tube 63 is big enough. In order to increase the latter, one can also implement multi-stage amplifier circuits. In order to increase the sensitivity of the magnet 9 without giving it unwieldy dimensions, it is advisable to dimension the amplifiers so that they are fully controlled even with relatively small deviations in the capacitance of the capacitor 6i, 62 from the trigger value. The magnet .Io, which causes the reduction in the follow-up speed, is fed in the circuit according to FIG. 6 by a special amplifier tube 70 , which is also controlled by the capacitor 61, 6a. The grid circle of the tube 7o is not as. Bridge formed, because firstly the same high degree of accuracy is not necessary here as with the Magneteng and secondly it is also desirable that the magnet 4o also remains in the released state when the aforementioned angle a is undershot and values in the vicinity of o or even takes on negative values.

In Figure 7 a circuit is shown in which a special auxiliary AC power source is dispensable. The variable capacitor 61, 62 here forms part of an oscillation circuit 71 in the grid circuit of the amplifier tube 63, which consists in a known manner of coils and capacitors 73 switched, namely these frequencies should be different from one another, and the damping of these two oscillating circuits should also differ from one another noticeably (in that the oscillating circuit 72 is given a special damping resistor 74). 75 and 76 are feedback coils, one of which, 75, is coupled to resonant circuit 72 and the other, 76, is coupled to resonant circuit 73. The magnets 9 and: Io are also connected here (with the shunt resistor 77) in the anode circuit of the tube 63 and adjusted so that "the magnet 4.o responds at a noticeably smaller current than the magnet 9. The oscillating circuits and the feedback are dimensioned in a known manner such that self-excitation occurs when the variable oscillation circuit 71 is matched to one or the other of the fixed oscillation circuits.

The mode of action is as follows: If a reaches the value ei, at which the magnet 40 reducing the follow-up speed is triggered should, then 71 is exactly matched to 73 and there is self-excitation and magnet 4.o attracts under the effect of the increased anode current. As a result of the strong Attenuation of the oscillating circuit 72, however, the anode current does not reach the value which is necessary to trigger the magnet 9. Rather, magnet 9 only attracts, when oscillating circuit 71 is coordinated with the other, less damped oscillating circuit 73 is what should be done with the value ca = o. It goes without saying that besides Other circuits are also possible for the circuits shown here.

In Figure 8, an embodiment of the invention is shown in which causes the control of the follower with the help of photoelectric elements will. The device required for this consists of one on the pointer shaft of the balance attached, with cutouts 89, 9o provided disc z, from the lamps 78, 79, Converging lenses 8o, 81 and the photoelectric cells 82, 83, which are attached to the trailer 2 are attached and execute a rotary movement concentric with the disk i can.

The mode of operation of the device is in principle the same as in the embodiments shown in FIGS. One photoelectric system, e.g. B. 79, 81, 82, is used to trigger the reduction of the follow-up speed before reaching the position of the follower corresponding to the balance setting z. The length of the associated cutout 9o in the disk i could approximately correspond to the length of the contact 7 in FIG. 1, this photoelectric system having to fulfill the task of the mating contact 12 (FIG. I). The overhead photoelectric system 79, 80, 83 and the associated cutout 89 in the disk i serve to trigger the lock 9 and can be compared with the contacts i and 8 in FIG and motor circuit).

In order to achieve a precise setting of the display device, was in all embodiments the speed of the adjusting member before it is reached of the setting corresponding to the balance setting so that within the release time of the lock the adjusting member at most one of a single reading unit covers the corresponding path. In order not to carry out the reduction to this extent to have to, one could for the same purpose the contact between the balance and the adjusting element close with a certain advance so that within the tripping time the lock the display device exactly in the direction corresponding to the pointer deflection Position is moved. The reduction of the follow-up speed would have to be in this Case only take place so far that within the tolerances of the tripping time of the locking magnet the display device is moved further with no more than one reading unit. If the tolerance of the release time of the locking magnet z. B. would be 2o% a, one could do the reduction in 1/5 of the time required by the previous methods reach. It goes without saying that besides those described here numerous other designs are possible which are within the scope of the invention; In particular, the device can be used on other measuring instruments in addition to scales will.

Claims (3)

PATENT CLAIMS: i. Adjustment device for transferring deflections of measuring instruments, in particular of automatic scales on a display or Printing device according to Patent 661 229, characterized in that for control which is the follow-up speed of the follower link (-?) before the final setting on the respective balance position reducing device as well as the with this connected blocking element (9) control elements (e.g. photoelectric cells, Capacitors, liquid contacts, sliding contacts or the like) are used by which in a known manner an action of the adjusting member (2) when setting , to the equilibrium position of the scales is avoided. 2. Adjustment device according to claims, characterized in that between the balance and the follower element (2) a mechanical-electrical Connection is provided, which allows mutual overtaking when the from the balance moving member or the adjusting member allows. 3. Adjustment device according to claims i and 2, characterized in that to induce the reduction the follow-up speed and the blocking of the follow-up movement are used by contacts, which only during the setting process by means of an electromagnet (TO) in the Area of their mating contacts or after setting the display device from the Area of their mating contacts are brought (Fig. 1, 2). , 4. Adjusting device according to claims i to 3, characterized in that the adjusting element (2) is electrically operated Coupling elements are connected in the grid circle of one or more Amplifier tubes are and that are used to control the tracking movement electrical parts are connected to the anode circuit of the tube or tubes. 5. Adjusting device according to claim i and 2, in which the contact is made through in a liquid container immersed, preferably needle-shaped contact fingers, characterized in that that the contact fingers (23 to 26) with the balance and the liquid container (3o to 33) are connected to the adjuster (Fig. 3). 6. Adjustment device according to claim 5, characterized in that the contacts moved by the balance (23 to 26) are guided in parallel by a link (29) (Fig. 3) so that the vertical Component of their deflection is proportional to the applied load. 7. Adjusting device according to claim 5 and 6, characterized in that with the help of the liquid contacts (23 to 26, 3o to 33) the ignition of the discharge in gas-filled rectifiers is influenced (Fig. 4.). B. Nachstellv device according to claim 4 to 7, characterized in that that the reduction of the follow-up speed and the locking of the adjusting member is effected with the aid of the same tube (d5) (Fig. 4.). 9. Adjustment device according to claims, 2 and .4 to 8, characterized in that to bring about the reduction of Follow-up speed electrical controls are provided that control the speed gradually decrease. ok 1 \ Tach adjusting device according to claim 9, characterized in that that on the balance pointer (i) and the adjuster (2) assignments (61, 62) of capacitors are arranged, the parts of the movement of the \ Tachstellgliedes (2) controlling electrical circuits are (Fig. 5). i i. Adjusting device according to claim 9 and io, characterized in that one or more capacitors in the grid circuit of amplifier tubes (63, 70) are connected (Fig. 6). 12. Adjustment device according to claim 9 to i i, characterized in that one or more capacitors with assignments (61, 62) that can move relative to one another, they form parts of oscillation circles (Fig.7). 13. Adjusting device according to claim 9 to 12, characterized in that that the two magnets (9, 4o), which reduce the follow-up speed or cause the shut-off of the follow-up movement from the anode droplets from amplifier tubes (63, 7o, Fig. 6) and controlled by the variable capacitors and their sensitivity is chosen so different that they are different for different Address capacitor settings. 1d .. Adjusting device according to claim 4 to 13, characterized in that the grid circles of amplifier tubes (63, 70, Fig. 6) are connected to oscillating circuits in a bridge circuit and the blocking magnet (9) has such a setting that it is triggered when the bridge is balanced is. 15. Adjusting device according to claim 14, characterized in that a variable and two fixed oscillation circles are provided and that one Magnet (9 or 40, Fig. 7) is triggered when the variable oscillation circuit is tuned to a fixed oscillation circuit and the other magnet is triggered becomes when the variable oscillation circuit on the other fixed oscillation circuit is matched. 16. Adjusting device according to claim r to 15, characterized in that that when using two photoelectric devices (78, 81, 82 and 79, 80, 83, Fig. 8) to control the to reduce the follow-up speed or the photoelectric devices are used to shut off the follow-up movement are arranged on the next link (s) and their exposure through one on the pointer shaft attached, with cutouts (89, 9o) provided disc (r) is controlled.