DE2447003A1 - SWITCH FOR FEEDBACK - Google Patents

Description

Dipl. Ing. H. Hauck

Dipl. Phys. W. Schmitz

Dipl. Ing. E. Graalfs

Dipl. Ing. W. Wehnert

Dipl. Phys. W. Carstens

2-Hamburg 36

Neuer Wall 41

ILLINOIS TOOL WORKS INC.

85ο1 West Higgins Road
Chicago, Illinois 60631 / USA

Hamburg, October 1, 1974

Switch with feedback

The invention relates to a switch with feedback, in particular to βχηβη switches with tactile feedback or feedback. Non-mechanical switches for use in switching,

Chalkboards and the like are being used to an increasing extent in modern day use Electronic systems have been used. One of the main reasons for this is that mechanical switches tend to unreliable in operation after a large number of operations due to corrosion, wear or erosion of the contacts and due to other mechanical ones Damage. In addition, mechanical switches always have the problem of contact bouncing, which generates fault signals that enable the correct operation of the associated facility can interfere.

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A number of types of switches including electronic, magnetic and Hall effect switches are available designed to perform non-mechanical electrical switching. One such device is shown in U.S. Pat 638 221 and may be used in connection with the present invention can be used. When the switch according to the aforementioned patent is a saturable magnetic core and a couple of permanent magnets used. The permanent magnets are on a stamp or switching part attached, which is depressed by the operator, which the state of the magnetic saturation of the magnetic core to determine whether an output signal should be generated or not.

Although various non-mechanical switches that have been developed operate satisfactorily for many uses work, they tend to be called to be considered unfavorable for many other uses due to the fact that the operator no positive indication is given when a switch has been operated. This is due to the lack of one Noise or any tactile effect in these switches, which in turn results from that essentially no mechanical process or no mechanical effect takes place. Consequently, this leads, although a non-mechanical one manually operated switches can inherently be exceptionally reliable, leading to an increase in Operator errors that occur during the operation of such switches and ultimately result in one Restriction of their wide range of application.

The invention therefore aims to create a switch which has a spring-loaded cam follower part, which is formed in one piece on a cam follower part carrier is and is actuated by a cam, which in turn • instückig on the actuating part of a mechanically actuated non-mechanical switch is formed, wherein the

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The actuation of the actuating part causes a / force build-up and a force release, which simulates the actuation of a mechanical switch for the operator.

Another purpose of the invention is to provide a / 3 Create mechanism with tactile feedback or tactile feedback for panel switches and the like, these precautions are taken to reduce operating errors by the operator, wherein the feedback mechanism has a three-dimensional control part, which is formed in one piece on the plunger of the switch, and has a cam follower part carrier which is removably attached to the housing of the switch and is biased by a spring which is located in a cavity is inserted in the housing so that the cam follower part carrier is movable along a first axis, and wherein the cam follower part carrier is a compliant or Has resilient arm, which the cam follower part carries so that the cam trailing part along a second Axis is movable when the actuating part of the switch is released from its fully depressed position will.

Another purpose of the invention is to provide a mechanism for tactile feedback to create, which on the housing of a manually operated, not mechanical switch is attached, which • inen formed in one piece on the plunger of the switch Cam part, a cam part trailing support and a coiled spring which is located in a cavity in the housing • is inserted and for resilient pretensioning of the cam follower subcarrier serves along a displacement axis which is perpendicular to the displacement axis of the plunger, wherein the force-displacement characteristic of the switch is preset during depression of the plunger can be, in ^ which the coiled spring and / or the control cam structure, which one is used is selected accordingly. -

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The invention is explained below with reference to the drawing for example explained.

FIG. 1 is a side view of the switch according to FIG present invention in the form of a partial cross-sectional view showing the beam biasing spring and shows the switch part return spring with the switch part in its not depressed state Location is located.

Fig. 2 is an end view of the switch with the switch portion in its depressed position Location is located.

Fig. 3 is a partial side view corresponding to Fig. 1, but the switching part is almost pushed down to the tipping point. ■

Figure k is a top plan view showing the sensing feedback mechanism in place within the switch housing.

Fig. 5 is a top plan view of the cam follower sub-carrier removed from the housing.

Fig. 6 is a. Stij & nansicht of the cam follower partial carrier s.

Figure 7 is a side view of the cam follower sub-carrier s.

Fig. 8 is a plan view of the cam portion of the switching portion of the switch.

Fig. 9 is a side view of the cam part of the switch part.

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Fig. 10 is a force versus travel graph for the switching part of the switch.

The sensing feedback mechanism according to the invention is open manually operated, non-mechanical panel switches applicable, it can also be applied to other types of switches which require a stimulus or a tactile one Influence is exerted on the operator, so that it is certain for the operator that the operation the switch has actually been made. The stimulus applied to the operator includes both a mechanically palpable effect and a sound. The tangible effect is achieved by means of a cam on the switching part of the switch and a cam follower part on a spring-loaded cam follower part carrier brought about. The loaded spring is selected to be the To control force or pressure build-up and the force or pressure release, which when the switching part of the switch is actuated appear. Noise is generated by striking the cam follower part generated on a part of the housing after the tipping point has been passed.

The present invention provides a relatively inexpensive addition to a non-mechanical switch, because only two new components are added to the switch and only on the switching part and on the housing changes to the switch are required. The two added components are made in one piece Cam follower part carrier made of plastic and one wound Preload spring for the carrier. The switching part of the switch, which is preferably made of plastic, must be designed in such a way that it also has a one-piece control cam, and the housing, which is also preferably made of plastic, has a cavity, which takes up the coiled preload spring, furthermore a / stop part for the cam follower part carrier and bracket

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protrusions for the carrier.

In addition to the. relatively low cost of the mechanism according to the present invention and its simplicity in construction, the mechanism according to the present invention is versatile, since the force-displacement characteristic of the switching part can be predetermined by selecting the correct coil preload and / or the cam structure beforehand. In addition, the mechanism is advantageous because of its linear return characteristic, which results from the fact that the return of the switching part to its initial position after being completely depressed is controlled almost entirely by the spring characteristics of the switching part return spring.

In FIG. 1, a non-mechanical switch is indicated generally by the reference number 20. The switch may be of the type described in U.S. Patent No. 3,631,221, but the particular construction of the switching mechanism used is immaterial to the present invention. The switch mechanism itself is located in the housing 22 and is operated by pressing down a switch part 2k . The housing and the switching part 24 are preferably made of plastic. The Fühlrückkoppe mechanism according to the present invention additionally requires only two parts for the non-mechanical switching of the switch 20. One of these parts is a one-piece cam follower part carrier, which is preferably molded from plastic and has the shape shown in FIG. The other part is the coiled biasing spring 28 for the cam follower part carrier 26. The Nookennachlaufteilträger 26 has a front wing 30 and a rear wing 32, which move under front and rear Hai terungsv or jumps "} h and 36 slidably so that the rear end 38 of the cam follower part 26 strikes against the stop part kO , which is formed in one piece on the housing 22 of the switch 20. The cam follower part 26 is detached from the housing 22 by applying pressure to the

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Cam follower part carrier 26 can be removed, namely by being displaced and raised to the right when looking in the direction of FIG. 4 when a recess 43 reaches the projections 34. The switch part 24 carries an integrally formed cam 42. When the switch part 24 is in a non-depressed position, as shown in FIG. 1, the end part 38 of the cam follower part carrier 26 is in the abutment position with the stop part 40. The cam follower member support 26 has a resilient arm 44 which is integrally formed on the front wing 30 so that it is supported in the manner of a cantilever and extends towards the rear wing 32. A cam follower part 46 is formed in one piece at the end of the arm 44, which preferably has a circular cross-section. With the switching part not depressed, the cam follower part 46 rests in the cam slot 48, as shown in FIG. 8, specifically at its lowermost position 50.

A tongue 52 protrudes from the lower part of the cam follower part carrier 26. The tongue 52 is used to receive one end of the coiled spring 28, the other end of the spring engaging the right hand wall 6 of the generally rectangular shaped cavity 58 formed in the upper portion of the housing 22. The longitudinal axis of the coiled pretensioning spring 28 lies along a line which is essentially parallel to the longitudinal axis of the elongated cam follower part carrier 26. The left side of the cavity 58 is provided with a recess 60 of smaller size than the frictional part of the cavity 58 in order to receive the cam follower part carrier when the switching part 24 is not depressed. The return spring 62 for the switch 24 is inserted so that it abuts the wall 64 of the switch part 24 at its upper end part and against a part of the housing or switch mechanism at its lower end.

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The operation of the switching mechanism according to the present invention can best be explained with reference to Figs. 8 shows an enlarged view of the cam section 42, which is formed in one piece on the switching part 24. The interaction between the control part or cam 42 and the cam follower part 46 and between the cam follower part carrier 26 and the pretensioning spring 28 defines the characteristics of the force build-up and the force release of the switch while the switch part 24 is pressed down to the tipping point 66 of the cam 42. The return spring 62 of the switching part 24 determines essentially by itself the return or return characteristic of the switch once the tipping point 66 has been reached.

When the switching part 24 is in its non-depressed position, as shown in Fig. 1,

. initially the cam follower part 42 / is essentially on its lowest point 50 on cam 42. That point corresponds to the origin in the diagram of the force over the path according to Fig. 10. A small amount of force is initially required to have any displacement at all due to the frictional drag and the initial loading effect of the return spring 62 to produce. The force required to overcome the initial load or the initial storage is represented by point 68 in FIG. When the force is increased and the switching part 24 is depressed, the cam follower moves 46 relative to the cam 42, so that it enters the groove 48 of the cam 42 and up to the point 70 is guided along.

Up to point 70 the spring 28 is not compressed been. As the depression of the switching part 24 continues, the cam follower part 46 relatively moves to the cam 42 so that it moves along the inclined wall 72. At this point it will be Cam follower part carrier 26 pressed to the left, when looking Fig. 7, through the spring 28 to the

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Cam follower part 46 reaches tipping point 66, FIG. 8. The position of the switching part 24 and the cam follower part carrier 26 at the tipping point 66 is shown in FIG. 3. The amount of force required to depress switch member 24 during this portion of the travel increases continuously as a function of the spring characteristics of spring 28, as shown by line 74 in FIG.

If the cam follower part k6 is moved past the tipping point 66 by pressing down the switching part 2k further, the cam follower part 46 is suddenly released to the left to point 76. This is a consequence of the force releasing effect of the spring 28 acting on the

Cam follower part carrier 26 acts. If the cam carrier ,
trailing part / 26 is brought to point 76, the left end part yo of the cam trailing part carrier 26 strikes the stop part kO on the housing 22 to thereby generate an operating sound which can be heard by the operator.

The force-displacement curve of FIG. 10 shows that if

the tipping point 66 has only been passed once that

the
the force release spring 28 is reduced by the amount of force necessary to keep the switching part 2k at its same level along the vertical axis of its displacement. The minimum amount of force required to do this is shown by line 80 in FIG. This amount of force is not sufficient to bring the switch 2k fully into its lower position, which occurs when the cam follower 46 is released along the base level 90 to point 82, since the return spring 62 for the switch member 24 is also slightly compressed when the switch 24 is moved beyond the toggle point 66 . The minimum amount of force required to move the switching part 24 in

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shifting its lowest position is represented by the line 8k in FIG. The shift to the lower position is shown by line 86. The actuation of the switch normally occurs in the vicinity of the tipping point 66 before the switching part Zk is brought into its lower position. After the cam follower part carrier 2.6 has been returned to its extreme left position along its horizontal displacement axis, the cam follower part k6 must be brought back to its starting point 50. To bring this about, the cam has kZ an inclined ramp 86 which has a rear edge 88, which is further away from the base level 90 than the leading edge 92. The cam follower piece k6, which is not guided from point 76 to point 50 , crosses the ramp 86 and then goes over the flat section 9k and finally over the waste area into the cavity 96, whereupon it returns to its initial position or reaches the starting point 50 when the switching part 2k returns to its non-depressed position. During this time, bends the arm kk inwardly and outwardly along an axis of displacement which the switching part Zk is disposed substantially perpendicular to the vertical axis of the shift and is also disposed perpendicular to the horizontal axis of displacement of the cam follower portion 26 as k in Fig. By the arrows are shown, which are drawn adjacent to the cam follower part k6. The arrows in the vicinity of the switching part Zk in FIG. 1 represent the movement path of the switching part Zk along the vertical axis, while the arrows drawn adjacent to the cam follower part carrier 26 in FIG. 3 represent the horizontal movement of the cam follower part. When the switching part Zk returns to its non-depressed position, the return force exerted on it is controlled essentially completely by the return spring 62, according to the line 98 in FIG.

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Claims (1)

Patent claims .) Manually operated electrical switch, consisting of a housing (22), a switching mechanism in the housing, a switching part (24) which can be pressed down along a first axis and has a cam (42), a return spring (62) for the Switching part (24), a cam follower part carrier (26) which is movable with respect to the housing (22) along a second axis which is arranged essentially perpendicular to the first axis, and the one resilient arm (44) with a cam follower part located thereon (46), and consisting of a pretensioning spring (28) which extends between part of the housing (22) and part of the cam follower part carrier (26) for preloading the cam follower part carrier (26) to an initial position and for preloading the cam follower part (46) a starting point, the resilient arm (44) being slidable along a third axis substantially perpendicular to the first and second axes, the Cam follower part (46) engages a first part of the cam (42) when the switching part (24) is pressed down to a tipping point (66), the cam follower part carrier (26) along the second axis against the force of the pretensioning spring (28) is arranged when the switching part (24) is pressed down on the tipping point (66) also so that the cam follower part (4-6) is suddenly driven towards a second point, the cam follower part carrier (26) in its initial position essentially along the second Axis is guided, and wherein the switching part (24) its return to its non-depressed position against essentially only the force of the return spring (62) and the cam follower part (46) its return movement to its starting point via a second portion of the cam (42) as Result of the - 12 - 509817/0262 Deflection or bending of the resilient arm (44) lengthways the third axis. 2. Switch according to claim 1, characterized in that the Housing (22) has a stop part (4O) and that the cam follower part carrier (26) against this stop part (40) is driven when the cam follower part (46) closes the second point is driven. 3. Switch according to claim 1, characterized in that the Cam follower part carrier (26) as a one-piece plastic part is trained. 4. Switch according to claim 3, characterized in that the Housing (22) has a stop part (4o) and that the cam follower part carrier (26) against the stop part (4o) is driven when the cam follower part (46) is driven towards the second point. 5. Manually operated electrical switch, consisting of 'a housing (22), a switching mechanism in the housing, which has a cavity (58) and first and second pairs of retaining projections (34, 36), one Switching part (24) which can be pushed down or pushed in along a first axis and has a cam (42), a Return spring (62) for the switching part (24) and consisting of a uniform cam follower part carrier (26), the first and second wing portions (30, 32) spaced from one another, the first Pair of the retaining projections (34) to the first wing part (30) is designed to overlap, the second pair of holding projections (36) to the second wing part (32) is designed to overlap, the cam follower part carrier (26) is displaceable with respect to the housing (22) along a second axis which is essentially perpendicular to the first axis is arranged, has a tongue (52) which protrudes into the cavity (5β) on the cam follower part (26) a compliant arm (44) with one thereon - 13 - • 509817/0262 Cam follower part (46), a coiled biasing spring (52) in the cavity (58) between the tongue (52) and a wall (56) of the cavity (58) for biasing the cam follower part (46) into an initial position and the cam follower part carrier (26 ) is arranged at a starting point, the resilient arm (44) is slidable along a third axis which is arranged substantially perpendicular to both the first and the second axis, the cam follower part (46) engaging a first portion on the cam (42) is arranged when the switching part (24) is pressed down to a tipping point (66) , the cam follower part carrier (26) is aligned along the second axis against the force of the biasing spring (28) when the switching part (24) over the Tilt point (66) is pressed down, so that the cam follower part (46) is suddenly driven towards a second point, the cam follower part carrier (26) essentially along the second axis in its initial position is returned, and wherein the switching part (24) its return movement in its not depressed position essentially solely against the force of the return spring ('62) and the cam follower part (46) its return movement to its starting point via a second part of the cam (42) as a result of the deflection of the compliant arm (44) along the third axis. Switch according to claim 5 »characterized in that the flexible arm (44) is supported in the manner of a free arm. Switch according to claim 5 »characterized in that the housing (22) has a stop part (4O) and that the cam follower part carrier (26) against the stop part (4O) is driven when the cam follower part (46) is driven to the second point /. - 14 - 509817/0262 8. Switch according to claim 7 »marked t, _ that the resilient arm (44) held in the manner of a free arm is. 9. Switch according to claim 8, characterized in that the resilient arm (44) is supported by the first wing part (30) and that the portion of the cam follower part carrier (26), which strikes against the stop part (4O), adjacent to the second wing part (32) is arranged. 10. Switch according to claim 9 »characterized in that the second part of the cam (42) has a ramp (72), move upwards from the second point to one ghost
flat part (94) which then sloped rapidly to a cavity that defines the first point. 11. Manually operated electrical switch, consisting of a housing (22), a switching mechanism in the housing (22), a switching part (2k) which can be pressed along a first axis and has a cam (42), a return or . Return device (62) for the switching part (2k), a cam follower part carrier (26) which has a cam follower part (46) which can be displaced with respect to the housing (22) along a second axis which is essentially perpendicular to the first Axis stands, and consists of a first and a second pretensioning device, wherein the second pretensioning device (28) is arranged essentially to pretension the cam follower part carrier (26) in an initial position and the cam follower part (k6) to a starting point, the second pretensioning device (44) is displaceable along a third axis which is substantially perpendicular to the first and second axes, the cam follower part (46) in engagement with a first part of the cam ns (42) is when the switching part (46) up to a tipping point (66) - 15 - 509817/0262 is pressed, the cam follower part carrier (26) is aligned along the second axis against the force of the second biasing device (28) when the switching part (24) is pressed down over the tipping point (66) , so that the cam follower part (46) suddenly on a second Point is driven closed, the cam follower part carrier (26) is retractable in its initial position essentially along the second axis, and the switching part (24) its return to its non-depressed position solely against the force of the return device (66) and the Cam trailing portion (46) can complete its return movement to its starting point over a second portion of the cam (42) as a result of the deflection of the first biasing means (44) along the third axis. ' 509817/0262 / 16 Blank