DE1253296B - Method and device for the heat treatment of feathers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int CL:

C21d

German KL: tat · ..n / m.

Number: 1253296

File number: H 36375 VI a / 18 C AmneMetag: May 13, 1959 Open date: November 2, 1967

The invention relates to the manufacture of springs aod refers in particular to movement and to a device for heat treatment for particularly high-quality installation purposes, such as controls or similar springs for displacement their feather conitants through simultaneous loading and warming. With this well-known »procedure, with which an artificially old can be achieved, the postponement of the Fcderkomtäaten after expiry an adjustable line canceled. The spring constants are thus shifted for all of them Springs about the same amount. The feathers therefore have before and after the treatment under Schjedllcne spring forces or L & agea. The spring forces for a given installation length are also at these feathers very differently, so that the Am The shot is very large.

With regard to the importance of springs as machine elements, their dimensions must be, how Wire thickness, Fcdcrdimcsscr, number of turns and Overall length, are continuously checked during manufacture. Even so, BSt cannot avoid that by changing cross-sections of the wire, different shepherds of the material, etc., which when shaping the feather in unequal dimensions, the finished feathers in the Fcdrrcharacteristic or «stiffness vary. In other words, the spring constants run differently inclined in the diagram or begin! at another point, so that nc run side by side.

But especially for high-quality installation purposes, e.g. B. The use of springs in regulators, valves or electrical relays, where oil stiffness affects the accuracy of the claim, depends on the test value based on the spring force at a given installation length in the case of the removal of the springs in an extremely small token area, which is so harder to keep in mind than the dimensions of the wire or spring diaphragm in the spring equation as factors io the fourth or third power occur. So it happens easily that even with the most careful attention the prerequisites for a tolerance test for 4 Feathers and selection after "good" and "Auischuß" the number of reject feathers that exceeds the goodfcdcm. But since such committee feathers elsewhere are hardly usable, they must practically be viewed as scrap.

The well-known setting of the springs, which at dea first loads cmc causes permanent change in shape of the springs, can be explained by the above Procedure are effected. It will be easier to do so

Method and device

for heat treatment of springs

Applicant

Hahn brothers, Scfiaiksmühte (Westphalia) Named as inventor: Kari-Gustav Hahn, Schalksmühle (Westphalia)

Way the setu wet when wrapping is pretensioned springs due to higher preload, with other timed springs by reducing the length and length of the springs

• o Considered for compression springs by increasing the WcXcI length.

The invention avoids such shortcomings. she goes from the knowledge known per se that when steel wires formed into springs are heated

»5 the hard, proportional limit, yield point and Tensile strength initially decrease, so that a greater, over the usual setting of the springs in a Permanent deformation going beyond the load is possible. However, they increase after cooling Strength values up to and beyond their initial values achieve e.g. with patented SlahJdräbteu Maximum value when the springs were heated to around 200 ° C. This increase in hardness, the proportionality, the yield strength and the bruc-

3S strength is likely to be due to an artificial aging process or to the reduction of the residual stresses created during winding. According to the invention is the displacement of the Fedcrkonstaotea when reaching a predetermined spring

4 »force (test value) with pre-determined egg bath length Springs finished. This gives the springs despite the different spring stiffness in one of the Load corresponding to the test value Llage or, in aadereo words, in the case of one of the test The springs have the same spring force when they are loaded the same desired spring force that is required for the response accuracy of the springs. the due to possible different inclines

The spring constants, which all run through the test value, result in unequal lengths of the Springs in the unloaded state are here with pleasure

7 «« tv w

3 4

accepted, since the springs in high quality F i g. 3 a device for the invention

Installation purposes, such as controls or the like, rarely treatment of coil springs in schematic

are completely relieved and an accurate spring force representation and

or spring length in this area is not necessarily F i g. 4 a loaded tension spring, also with a spring required is. So the test value is from these 5 diagrams.

Springs observed, so that the committee and thus the in F i g. 1 shown device for treatment

the production costs of springs, which are used in the treatment of helical compression springs, their length with

load have the same length as the test load, is deliberately oversized, consists of

can be reduced significantly. a scale 4 loaded with a weight 3, the

It is advisable, according to the invention, for the duration to which a plunger 5 is assigned as a counter bearing. the advantageously under weight load with a depending on the scale 4 is designed as a table scale, so that Type of steel at a temperature of around 200 or 250 ° C - the side parts 6 and 7 of the balance always parallel to the rature, expediently by passing electrical bearing part 8 through. The side part 6 carries a see current taking place heating, the duration of which shell 9 for receiving weights 3, the duration of which the achievement of the weight corresponding to the test value within the permissible pressure load of the the length is to be limited by one lying on the spring to be treated, while the side length change the springs responsive control part 7 is provided with a damper 10, which the To regulate the electric circuit, in which after reaching the settling time of the balance is significantly reduced and Test value corresponding length by closing the balance part gives such inertia where control circuit the heating circuit interrupted 20 by very large differences in force due to insufficient and at the same time, the treated spring is completely made of weight-relieved adhesive wire. and then be counterbalanced by one of the weight relief. When the warmed up ordered movement of the control current again- springs at the moment of the discharge all the is switched. The weight-bearing force will expediently exert the same force on the balance system, see above stung in the inventive treatment of 25 would be the different temperature of the Feather differently, proportionally less individual feathers, due to the different chosen as the spring test load. The defor- length during manufacture, on the spring force in the ermung speed the springs can have an effect by being cold. Balancing this a damper can be delayed. Differences are taken over by the damper in that the

To carry out the method, a pre-deformation acceleration in the balance system can be a

direction are used, which opposes a force according to the invention. An abnormally long or strong one

known per se, the inclusion of the spring to be treated is higher due to the longer deformation time

The clamping device serving the springs is heated with two, achieves a greater deformation acceleration

at the ends of the springs acting on the parts and is affected by the inertia of the balance

has, of which at least one is movable and relieved 35 systems at a low force, so that

is resilient. Advantageously, the movable force value and, after cooling down, the required force value is achieved

Resilient part assigned to a motion damper. will. This can also make very different

The resilient part of the jig can be compensated for by spring forces when the inertia

in the manner of a table scales with a higher adjustable scales system and the deformation speed

Be formed ble stop contact. Inventiveness can be set once after the spring,

according to it is recommended that the balance part against- The side part 6 is at its lower end with a

overlying part of the jig advantageous plate 11 is provided against which the to be treated

adhere to train as a plunger which is supported by a toothed helical compression spring 12. The plunger 5 is located

Rod drive can be raised and lowered. This can be in the line of action of the side part 6 and is on

expediently provided with a plate 13 at its upper end by means of a locking device in the form of 45,

an angle lever can be determined, one of which, against which the spring 12 with its other end

provided with a ratchet-like nose arm with supports. The plunger 5 is slidably mounted and

one arm of the plunger can be coupled and by one on the can manually with the lever 14 and the gear

other arm of the bell crank engaging spring in 15, which is in a corresponding toothing of the

Locked position can be retained. The locking device 50 engages plunger 5, are moved. The plunger 5 is

can be swiveled out by a relay, which is also connected to an adjustable stop 16

a control circuit is that see through one on, the one with a double switch 17 and one

Stop for the balance part and one on this locking device 18 is in operative connection. the

provided tongue formed contact controllable locking device 18 is pivotable on bearing 22

is. The spring to be treated is fastened between it and consists of an angle lever 19,

forming parts of the clamping device in front of which arm 20 is provided with a locking lug 21,

part of the transmission contacts of one of the heating that the stop 16 and thus the plunger 5 in his

the spring serving electrical heating circuit, the spring 12 holds the loading position. At the other

the one with the control circuit through a common arm 23 of the angle lever 19 is on a pin 24

seeds and operable by the plunger arm Dop 60 is provided a tension spring 25 which is attached to the frame of the

pel slide is interruptible. Device engages at a fixed point 26 and the

In the drawing, the invention is held in execution locking device 18 in its operative position. Remote

Approximate examples shown, namely shows ner is on the arm 23 of the angle lever 19 a

F i g. 1 articulated a device for the rod 27 according to the invention, which as a magnetic core with the

Treatment of helical compression springs in schematic 65 electromagnet 28 is in operative connection. At the

Table representation, turning on the electromagnet 28 is the rod

F i g. 2 a loaded compression spring with a spring slide 27 made of a magnetizable material,

grams, drawn into the solenoid so that the angle

I 253 296

5 6

lever 19 is pivoted and the locking lug 21 in the F i g. 2 is a finished screw pressure

comes out of engagement. spring 12 with the associated spring diagram

The operation of the device is as follows: put. The spring 12 is loaded with the test load in FIG. 1 is the device for treatment and therefore has the length a, which corresponds to the installation length of helical compression springs in the operative position shown in FIG. The length b indicates the length of the spring in the position, ie the spring 12 to be treated is in the unloaded state, while the length c indicates the plates 11 and 13 and is the length of the spring 12 before the treatment. In burdened by the weight 3. At the same time, the difference between the spring 12 is traversed by a heating current of the drawing, the length b and c for a better illustration of the relative connection contacts 29 via the line 30, io moderately large. In practice, this switch 17 and line 31 to the plate 13 and difference is approximately up to 2 mm. In the case of a very precise manufacture of the spring with high quality via the line 32, bearing part 8, the balance beam and the side part 6 is guided to the plate 11. Spring steel the difference is even only a few. As the current flows through the spring, it is 12 tenths of a millimeter. In the diagram, the characteristic is this is heated. The voltage of the heating current 15 lines of another spring, shown in phantom, is selected to be very low, about 24 volts, so that it is not dangerous for the operator. Extra-tensioned spring, while the length of the untreated one, this tension corresponds to the length e , depending on the wire size and the length of the spring. Even with this wire length of the spring 12, the characteristic curve of the treated spring structure and uneconomical test goes through to 20 through the test value Pr, so that the length of the heating times concerned is avoided. loaded spring again corresponds to the length α. the

As a result of this heating, the strength and characteristics of the finished springs 12 are now reduced despite the elastic limit of the spring mechanism in the unloaded state of different lengths, so that the spring 12 passes through the test point Pr as the weight 3 due to the action of the springs 25 springs 12 different spring strips that are compressed beyond the normal slump. After reaching a spring length (installation length) determined by different slopes of the spring, a characteristic curve will be expressed. This means that the finished control circuit, the voltage of which is also approximately 24 volts springs, is now closed with the same load, which is approximately the. This is done by a test load, that is, the test load is contact tongue 33, which is attached to the side part 6 of 30 by about 6% less than that of the desired scale 4 and the required spring force when it drops installation length, is selected with an adjustable stop contact 34 comes into contact with the same measure with extremely low tolerances. The control circuit is now from being compressed or that with the same the connection contacts 35 over the lines 36 installation length α (loaded spring length) with extremely and 32, bearing part 8, the balance beam, side part 6, 35 low tolerance equal forces through the contact tongue 33, contact 34, line 37, switch spring are dispensed. With the remaining

17 and line 38 and via line 39 with the formation of the spring is by shortening the Electromagnet 28 in connection, so that this verStange the unloaded spring of the spring diameter somewhat 27 moves in and thus increases the locking device. This changes the spring stiffness.

18 disengages. As a result, the plunger 5 40 Since the spring is only pulled down a very small amount by springs or the like. Is immediately shortened, the change in the spring stiffness is hardly in time is measurable by the lowering of the and does not change anything in the fact that the stop 16 attached to the identification plunger of the double line of the finished spring passes through the test point Pr , switch 17 is actuated , so that heating and control current as the contact 34 are switched off when the installation length α is reached. The locking device 18 will switch off the device with the control current,
now in the operative position again by the spring 25. 3 device shown is used. The finished spring 12 can now be used from the preliminary treatment of tension springs. For this reason, the device is removed from the direction and a new one is placed on the plate 13 in relation to the device according to the spring. This Fig. 1 modified so that the compression spring to be treated is dimensioned so that the desired 50 spring 41 is subjected to train. The weight 3 spring force in the test value required length is deliberately exceeded in the shell 9 on the side part 7, since this is arranged by the heat treatment, and the contact tongue 33 is reduced in the event of a development. The plunger 5 is then raised by upward movement with the contact 34 in touch with the lever 14 and the gear 15, which is in a position while the plunger 5 engages in its lower toothing of the plunger 5. Since 55 position is in the operative position. For the sake of simplicity, the stop 16 meets a guide surface 40, which in this figure is the electrical connection locking lug 21, so that the locking device has been omitted because the circuit of the pivots until the upper position of the in F i G. 1 corresponds to shown.

The plunger 5 the locking device with the aid of the spring The tension spring 41 is by means of the plunger 5 and 25 returns to its locking position. By means of the hooks 42 provided on the side part 6 of the balance 4 Upward movement of the stop 16 was clamped at the same time and 43 and is powered by a heating current, timely the double switch 17 is actuated, which can now be switched off by the switch 17, again assumes its on-position while the rivers are flowing, and thereby heated, so that an over-screaming feather 12, the plate 11 and thus the side part 6 th of the elastic limit is reached. Under the has raised, so that the contact tongue 33 65 action of the weight 3 is therefore the spring 41 no longer pulled apart with the stop contact 34 or the bias commitment. So that the starting position of the spring is permanently reduced again until the contact tongue achieved. 33 with the stop contact 34 in contact

comes. This closes the control circuit, and the electromagnet pivots the locking device 18 out of its operative position. Through this the plunger 5 is raised by spring force or the like and the switch 17 is raised by the stop 16 actuated, which thereby opens the heating and control circuit. The finished spring can now be removed from the hooks 42 and 43 are unhooked and a new spring hooked in. This tension spring 41 is dimensioned so that the length required for the desired spring force in the test point has not been reached or that the im Test point required preload for the desired spring force has been exceeded because the tension spring is lengthened by the heat treatment or loses its prestress. The plunger 5 is now again brought by the lever 14 in its clamping position. Thus the starting position is reached again.

The F i g. 4 shows a tension spring in the loaded state with the associated spring characteristic. This diagram is also similar to that of FIG. 2 the characteristic curve of another spring is drawn in dash-dotted lines. The spring, the characteristic curve of which is indicated by dash-dotted lines in the diagram, had a relatively high preload, which was reduced by the treatment according to the invention. The spring, the characteristic curve of which is shown with full lines, also had a preload which was completely eliminated by the treatment according to the invention and the spring was additionally pulled apart in a somewhat permanent manner. so that the turns of the relaxed spring no longer lie against one another. The characteristics of the finished springs in turn all run through the test point Pr. It does not matter whether the preload of the springs is reduced and / or the lengths of the unloaded springs are increased during the treatment of the springs. The finished spring always has the same tensile force with very small dimensions and the same length in the loaded state.

As already mentioned, the invention is not limited to the illustrated embodiments. Much more many other designs and applications are possible. So can the procedure also used in the manufacture of spiral springs, in particular leaf springs as contact springs and the design of the device can be varied in a variety of ways. So could z. B. the height-adjustable The plunger 5 can be raised and lowered by machine, with the drive required for this can be controlled by the existing control current. Furthermore, it is useful in many cases, the To subject feathers to general heating prior to the treatment according to the invention, the internal stresses caused by the winding of the springs in the springs can be eliminated. Further In particular, the compression springs can be attached to a mandrel during the treatment according to the invention or inserted into a tube to prevent the springs from buckling.

Patent claims:

1. Heat treatment process for particularly high-quality installation purposes, such as controls Od. Like. Serving springs to shift their spring constants by simultaneous Loading and heating, characterized in that the displacement when a predetermined spring force (test value) is reached is terminated at a predetermined installation length of the springs (12, 41).

2. The method according to claim 1, characterized in that the temperature at the Heat treatment corresponds to the temperature customary in known artificial aging.

3. The method according to claim 1 or 2, characterized in that the heat treatment of the Springs by a responding length when the length corresponding to the test value is reached Control circuit is terminated.

4. The method according to one or more of claims 1 to 3, characterized in that the deformation speed of the springs (12, 41) is delayed by a damper (10).

5. The method according to claim 4, characterized in that after reaching the test value corresponding length and completion of the heat treatment, the springs (12, 41) at the same time be relieved of weight.

6. The method according to one or more of claims 1 to 5, characterized in that the load on the springs (12, 41) during heating deviates proportionally from the test value is chosen.

7. Device for performing the method according to one or more of the claims 1 to 6, characterized by a known per se, the inclusion of the to be treated Spring (12 or 41) serving clamping device (5, 6) with two at the ends of the springs (12, 41) attacking parts (5 and 6), of which at least one is movable and loadable.

8. Apparatus according to claim 7, characterized in that the movable and resilient Part (6) is assigned a motion damper (10).

9. Apparatus according to claim 7 or 8, characterized in that the resilient part (6) the clamping device is designed in the manner of a table scale (4).

10. Apparatus according to claim 9, characterized in that the balance part (6) is an adjustable Stop contact (34) is assigned.

11. The device according to one or more of claims 7 to 10, characterized in that the part (5) of the clamping device opposite the balance part (6) is designed as a ram and can be raised and lowered via a rack and pinion drive (15) and with an automatically acting Locking device (18) can be determined in the operative position.

12. The device according to claim 11, characterized in that the locking device (18) is designed as an angle lever (19), one of which is provided with a ratchet-like nose (21) Arm (20) can be coupled to an arm (16) of the plunger (5), while the locking device (18) in its locking position holding spring (25) on the other arm (23) of the angle lever (19) attacks.

13. Apparatus according to claim 11 or 12, characterized in that the locking device (18) can be swiveled out by a relay (28), which in one of the stops (34) contact-controllable formed for the balance part (4, 6) and a tongue (33) provided thereon Control circuit (32, 37 to 39).

Claims (15)

comes. As a result, the control circuit is closed and the electromagnet swivels the locking device 18 out of its operative position. As a result, the plunger 5 is raised or the like by spring force and the switch 17 is actuated by the stop 16, which thereby opens the heating and control circuit. Now the finished spring can be unhooked from the hooks 42 and 43 and a new spring can be attached. This tension spring 41 is dimensioned so that the length required for the desired spring force at the test point is not reached or the preload required for the desired spring force at the test point is exceeded, since the tension spring is lengthened or loses its bias due to the heat treatment. The plunger 5 is now brought into its clamping position again by the lever 14. Thus the starting position is reached again. The F i g. 4 shows a tension spring in the loaded state with the associated spring characteristic. This diagram is also similar to that of FIG. 2 the characteristic curve of another spring is drawn in dash-dotted lines. The spring, the characteristic curve of which is indicated by dash-dotted lines in the diagram, had a relatively high preload, which was reduced by the treatment according to the invention. The spring, the characteristic curve of which is shown with full lines, also had a preload which was completely eliminated by the treatment according to the invention and the spring was additionally pulled apart permanently. so that the turns of the relaxed spring no longer lie against one another. The characteristics of the finished springs in turn all run through the test point Pr. It does not matter whether the preload of the springs is reduced and / or the lengths of the unloaded springs are increased during the treatment of the springs. The finished spring always has the same tensile force with very small dimensions and the same length in the loaded state. As already mentioned, the invention is not limited to the illustrated embodiments. On the contrary, many other designs and applications are possible. Thus, the method can also be used in the production of spiral springs, in particular leaf springs as contact springs, and the design of the device can be modified in many ways. So could z. B. the height-adjustable plunger 5 can be raised and lowered by machine, the drive required for this being controllable by the existing control current. Furthermore, it is useful in many cases to subject the springs to general heating prior to the treatment according to the invention, the internal stresses caused by the winding of the springs in the springs being eliminated. Furthermore, in the treatment according to the invention, the compression springs in particular can be attached to a mandrel or inserted into a tube in order to prevent the springs from buckling. Patent claims: 1. Heat treatment process for particularly high-quality installation purposes, such as controls Od. Like. Serving springs to shift their spring constants by simultaneous Loading and heating, characterized in that the displacement when a predetermined spring force (test value) is reached is terminated at a predetermined installation length of the springs (12, 41). 2. The method according to claim 1, characterized in that the temperature at the Heat treatment corresponds to the temperature customary in known artificial aging. 3. The method according to claim 1 or 2, characterized in that the heat treatment of the Springs by a responding length when the length corresponding to the test value is reached Control circuit is terminated. 4. The method according to one or more of claims 1 to 3, characterized in that the deformation speed of the springs (12, 41) is delayed by a damper (10). 5. The method according to claim 4, characterized in that after reaching the test value corresponding length and completion of the heat treatment, the springs (12, 41) at the same time be relieved of weight. 6. The method according to one or more of claims 1 to 5, characterized in that the load on the springs (12, 41) during heating deviates proportionally from the test value is chosen. 7. Device for performing the method according to one or more of the claims 1 to 6, characterized by a known per se, the inclusion of the to be treated Spring (12 or 41) serving clamping device (5, 6) with two at the ends of the springs (12, 41) attacking parts (5 and 6), of which at least one is movable and loadable. 8. Apparatus according to claim 7, characterized in that the movable and resilient Part (6) is assigned a motion damper (10). 9. Apparatus according to claim 7 or 8, characterized in that the resilient part (6) the clamping device is designed in the manner of a table scale (4). 10. Apparatus according to claim 9, characterized in that the balance part (6) is an adjustable Stop contact (34) is assigned. 11. The device according to one or more of claims 7 to 10, characterized in that the part (5) of the clamping device opposite the balance part (6) is designed as a ram and can be raised and lowered via a rack and pinion drive (15) and with an automatically acting Locking device (18) can be determined in the operative position. 12. The device according to claim 11, characterized in that the locking device (18) is designed as an angle lever (19), one of which is provided with a ratchet-like nose (21) Arm (20) can be coupled to an arm (16) of the plunger (5), while the locking device (18) in its locking position holding spring (25) on the other arm (23) of the angle lever (19) attacks. 13. Apparatus according to claim 11 or 12, characterized in that the locking device (18) can be swiveled out by a relay (28), which in one of the stops (34) contact-controllable formed for the balance part (4, 6) and a tongue (33) provided thereon Control circuit (32, 37 to 39). 14. The device according to one or more of claims 7 to 13, characterized in that the springs to be treated (12, 41) between receiving parts (11, 13; 42, 43) the jig are in an electrical heating circuit (30 to 32). 15. Apparatus according to claim 13 and 14, characterized in that the heating current and the control current through a common double 10 pel switch (17) can be interrupted, which can be actuated by the arm (16) on the plunger (S) Considered publications: U.S. Patent No. 2,254,525; "Construction", 1953, p. 342;
Material manual "Steel and Iron", 3rd edition 1953, p. Q11-2. 1 sheet of drawings 7 »βΟ / 2β1