DE2200337A1 - Electric door switch - Google Patents

Description

DiPL.-ING. GÜNTHER ESSENführer DIPLo-INQ-DIETER K. S P E! S E R 2200337

PATENT LAWYERS

File number: New registration 28 BREMEN BORGEMEISTER-SMIDT-STH. Applicant name: Molex Incorporated ' ₍ τ β ι ν Ί dad - κ α υ β)

TELEPHONE: (0 «1)« 11977 TELEQRAMS: FERROPAT

BREMER BANK 1008072 POST CHECK HAMBURG 255757

US. CHARACTERISTICS: M 193

Date: December 28, 1971

MOLEX INCORPORATED, incorporated under the laws of the State of Illinois, 5224 Katrine Avenue, DOWNERS GROVE , Illinois 60515 (V.St.A.)

Electric door switch

The invention relates to an electric door switch, consisting of a housing with means for attaching it on a door frame, from a pair of switching contacts, one of which is movable and occupies a closed and an open contact position can, and from a back and forth on the housing between a door-open position and a door-closed position mounted release with a cam device, which is on the moving contact in the door. Acts in the closed position of the trigger and displaces it into one of its two contact positions, ^ * 7ogegen the moving contact assumes the other contact position with respect to the other contact when the trigger is released is in its door-open position.

The closed position of a trigger of a door switch ^ is known by the location of the closed door

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determined in relation to a door frame on which the door switch is mounted. Significant amounts occur with refrigerator doors Differences in distance between the door and the door frame, mainly due to different Installation conditions for an elastic door seal, which elastically fills the gap between the door and the door frame when the door is closed. Even with a certain one In the refrigerator model, there are tolerances in the door gap, which the seal elastically compensates. It glows one that, for these reasons, the actuation path of the door switch trigger and its end position when it is closed Refrigerator door must have very different values, which also change over the life of a refrigerator Change refrigerator. The consequence of this is unsafe operating conditions with known door switches.

Another problem with known refrigerator door switches is the moisture in their housings can accumulate and short-circuit their switching contacts. The moisture can be caused by condensation or by cleaning the inside of the refrigerator. Regarding the latter possibility it can be said that the switch housing is largely sunk in the door frame, while the opening for the actuating button protruding outward is not sealed against the ingress of water. You can wipe it with a wet cloth or sponge via the door frame, so water can easily penetrate into the switch housing and short-circuit the switch contacts and / or allow it to corrode over time.

It is therefore the object of the invention to design a door switch particularly suitable for installation in refrigerators in such a way that that it works perfectly under all installation conditions and tolerances between the door and the door frame

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switches, it does not matter whether the switch is set up as a normally closed contact or a normally open contact. Further it belongs to the object of the invention to design the door switch so that there is no or within its housing essentially no water can accumulate and short-circuit or corrode its contacts.

According to the invention this object is achieved in that the cam device and the movable contact are coordinated so that the cam device the movable contact on the first part of the actuation path of the trigger in the direction of its door-open position in its door-closed position in the one contact position moves while the cam device throughout the remainder of the trigger travel in the door-closed position continues to hold the movable contact in this contact position; and that the The cam device in the door-open position of the trigger is at a distance from the movable contact, which is overcome on the first actuation path piece when the trigger touches the movable contact.

This arrangement has the advantage that the switching state of the Switching contact pair is made, which is intended with the door closed, while in the course of the further Inward movement of the trigger this switching state is maintained. This will remove all tolerances and bmuart deviations effectively balanced between the door frame and door of a refrigerator.

The pair of switching contacts of the door switch can be designed as a normally closed contact or as a normally open contact when the refrigerator door is open be. A normally closed contact when the refrigerator door is open

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door can be used, for example, to control an indoor fan while having a normally open contact with the door open to switch on the interior lighting of the refrigerator. It is possible on one Install two door switches each with one of the mentioned contact types in the refrigerator.

Advantageously, the cam device in a first surface section with a small radius of curvature which acts first on the movable contact, and in be divided into an adjacent second surface section, the radius of curvature of which is substantially larger and which acts on the moving contact on the further actuation path.

It is particularly advantageous to mount the trigger in the switch housing, which can be pivoted in an opening of the Housing is stored. In the course of this pivoting movement, the rounded tip of the cam brings the movable " Contact quickly to the fixed contact, provided it is a normally open contact set with the door position open acts. If, on the other hand, a normally closed contact is provided, the cam pushes after a short pivoting path of the Trigger the two contacts quickly apart, while in both cases over the remaining, but larger Swivel angle component of the release the specified contact position, which corresponds to the contact state when the Door corresponds, is permanently adhered to by the cam of the trigger with its back over the movable Contact slides away.

Advantageously, the switch housing can be equipped in its interior with an intermediate wall, which a water barrier between the switch contacts and the

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represents front housing opening. In addition, one or more openings can be made in the base plate of the housing be provided through which any water that may have penetrated can drain.

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Below are some preferred embodiments, the invention explained in more detail with reference to a drawing. Show it:

Fig. 1 is a front view of a refrigerator

with indicated built-in door switches according to the invention;

FIG. 2 shows a partial section on an enlarged scale along a line 2-2 of FIG door switch contacts open when refrigerator door is open;

3 shows a partial section corresponding approximately to a line 3-3 of FIG. 2, in a further enlarged Scale;

Fig. 4 is a partial section taken along line 4-4 of Fig. 3 showing details of the door switch;

Fig. 5 also shows a section in the course of

Line 4-4 of Fig. 3, but with the refrigerator door closed Switching status of the door switch;

6 shows an illustration of a modified door switch, essentially corresponding to FIG. 4 with normally closed contacts when the refrigerator door is open;

FIG. 7 shows the door switch from FIG. 6, but with the refrigerator door closed; FIG.

8 shows a perspective illustration of a housing for a door switch according to the invention, with the housing cover removed; and

Fig. 9 is a perspective individual view of a switch trigger, as it is in the inventive Door switches is used.

A shown schematically in Fig. 1 in front view Refrigerator 2 has an essentially right-angled cre

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designed door frames 4 with a door opening 6. How into · special can be seen in Fig. 2, is a door with hinges 10 on the door frame 4? she lets herself out a closed position indicated by broken lines into an open position drawn with continuous lines Move position and vice versa. One edge of the door 8 is covered with a seal 12? which is in the closed Door condition sealing against a door post 14 places.

In the door post 14 there is a recess 16 for accommodating a switch housing 18 made of plastic. On two side walls 28 and 30 of the switch housing 18 there is an integrally molded locking arm 20? the

Locking arms 20 are opposite one another in such a way that they hold the switch housing 18, once pressed into the recess 16, like a barb, in that toothed fingers 22 at the ends of the locking arms 20 rest against opposite edges of the recess 16 with elastic deformation of the locking arms 20. Furthermore, it can best be seen from FIG. 8 that the switch housing 18 has an integrally formed front cover plate 24 which, when installed, covers the recess 16 and rests on the outer surface of the door post 14. With the aid of a small screwdriver or a similar lifting tool, the switch housing 18 can easily be removed from the recess 16 by reaching under the cover plate 24.

In the switch housing 18, either according to FIGS. 4 and 5, a switch S, which is open in the idle state, or according to FIG. 6 and 7, a switch S _{2, which is} closed in the idle state, is installed. The switch S, which is open in the idle state, can be accommodated within the refrigerator 2 for controlling a

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Fan can be used while the switch S «can be used to control the interior lighting of the refrigerator; If the refrigerator door 8 is opened, the switch S ₁ switches off the fan, while at the same time the switch S_ switches on the interior lighting of the refrigerator. The opposite conditions naturally exist when the refrigerator door 8 is closed; now switch S ₉ turns off the interior lighting and switch S starts the fan again.

The housing 18 also has a transition at right angles into the rear wall 32 and into the two side walls 28 and 30 Bottom wall 26. Furthermore, according to FIG. 3, a cover 34 with an inner flange 35 is attached to the housing walls 28, 30 and 32. The side wall 30 and the rear wall 32 close a vertical slot 36 for receiving a movable contact 38 or 38a between them. The contact 38 or 38 a has a lateral connection tab 40, which by a Opening in the cover 34 protrudes to be connected to a line in the fan circuit of the refrigerator. The movable contact 38 or 38a is a flat tempered brass leaf spring with two angled to one another Legs 42 and 44 are formed, which are connected to one another via an arcuate transition piece 46. At the free At the end of the leg 44 of the movable contact 38 is a riveted silver point contact, for example 48. Another corner of the switch housing 18 formed between the side wall 28 and the rear wall 32 is located vertical slot 50 for receiving a fixed contact 52 or 52a, which is provided with a connection tab 53, which protrudes through another opening in the cover 34, around there with another line from the fan circuit to be connected. Outside the slot 50 is

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the fixed contact, which is also designed as a flat sheet metal 52 bent in the direction of the clamped leg 42 of the movable contact 38? and at his free End is a point contact 54 riveted, which the Silver contact 48 is opposite »

In the interior of the switch housing 18 extends between the two side walls 28 and 30 and in front of the point contact 54 an intermediate wall 56 with a slot 57 in its center, which the two legs 42 and 44 of the movable Contact 38 = in the bottom wall 26 swei openings 58 are arranged in front of the intermediate wall 56, which are provided for the discharge of any condensation water present in the space in front of the partition 56 and for ventilation are. If necessary, the bottom wall 26 can be provided with a further opening 59 on the rear wall 32, so that any condensation water that arises in the tree between the rear wall 32 and the partition 56 can run off »

On the front of the switch housing 18 there is an opening 60 for receiving a trigger β2 made of plastic. As can best be seen in FIG. 9; This trigger 62 has a circular sector-shaped basic shape and consists of two parallel plates 64 and 66 with one-piece molded pivot pins and 69 at the pointed end of these two plates 26, while the opposite pivot pin 39 is rotatably mounted in a bearing block 72 on the inside of cover plate 24. If the cover 34 is then placed on the holder housing 18, the face of the upper pivot pin (39 abo

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Between the two narrow ends of the plates 64 and 66 there is a torsion spring 74, which presses with one end 76 from the inside against the side web of the trigger 62 connecting the plates 64 and 66 and which presses with its other end 78 into a gap between the side wall 28 and a nose 80 is inserted, which protrudes from the bottom wall 26 of the switch housing 18 at a distance from the side wall 28. According to FIGS. 4 and 5, the torsion spring 74 exerts an outward pressure on the trigger 62 of the switch S ₁ , so that this is pivoted out of the switch housing 18 as soon as the door 8 of the refrigerator 2 opens (see FIGS 4). If, on the other hand, the door 8 is closed, as indicated in broken lines in FIG. 2, it presses the trigger 62 against the force of the torsion spring 74 largely into the interior of the switch housing 18, the contacts of the switch S being closed.

Between the two plates 64 and 66 of the trigger 62 there is an integrally molded cam 82 which slides along the movable contact 38 or 38a when the associated switch S or S _{2 is} actuated. When the door 8 is open as shown in FIG. 4, the cam 82 is some distance away from the movable contact 38. An effective cam surface 84 on the circumference of the cam 82 extends from a rounded tip 85 into an area 87 with a large radius of curvature / if the door 8 is closed and the trigger 62 is rotated into the switch housing 18, the rounded tip 85 of the cam 82 first engages the movable contact 38 and quickly brings the two opposing point contacts 48 and 54 into mutual contact; as the trigger 62 continues to rotate

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The area 87 only slides further on the transition piece 46 of the movable contact 38 along while the point contacts 48 and 54 remain permanently closed »This ensures that the point contacts 48 and 54 with Security are already closed before the seal 12 lies against the door jamb 14, regardless of existing ones Tolerances and variants in the refrigerator construction. The size of the free travel that the trigger 62 after the closing of the switch contacts 48 and 54 still executes, may be different, but preferably extends this idle travel over the greater part of the total trigger pivot angle. Viewed the other way round, the initial actuation travel of the trigger 62 extends between it outer end position and the closing of the switch contacts 48 and 54 only about a small fraction of the total Actuation travel of the trigger,

You can always see how housewives treat you Wet rag or sponge around the door switch of a refrigerator. Since here the penetration of water through the opening 60 into the switch housing 18 cannot be ruled out, there is at least the possibility that this water through the openings 58 expires again.

The other type of switch S _? with contacts closed in the idle state according to FIGS. 6 and 7 is accommodated in the same switch housing 18 with trigger 62 as the switch S described above. As already mentioned, switch S. is closed in the idle state, that is to say when the refrigerator 8 is open; a refrigerator light connected to the switch S ₂ and not shown in the drawing would now be on. When the door 2 is open, there is a point contact 48a. of the

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speaking biased movable contact 38a on one Counter contact 54a, which is riveted into the fixed contact 52a. The point contacts 48a and 54a correspond to Point contacts 48 and 54 of the switch S-. The trigger now moves during the closing movement of door 8 62 from its open position according to FIG. 6 inside the housing into its closed position according to FIG. 7, so runs first the rounded tip 85 of the cam 82 against the movable contact 38a and separates the two point contacts 48a and 54a from each other. In the course of the continuing closing movement of the door 8, the area 87 of the cam 82 slides with the large radius of curvature under the angled part of the movable contact 38a and holds the two opposing point contacts 48a and 54a are constantly separated from one another.

In summary, the invention relates to an electric door switch for refrigerators or the like, consisting of a sunk into a door post, insertable housing, a set of switch contacts within the housing, and off a release button that protrudes from the housing and is pushed into the housing when the door is closed. The switching contacts are actuated within a relatively short initial part of the door closing movement. In the course of the further closing movement of the door, the switching contacts retain the state they were in when the door was closed Take the door. The interior of the housing is provided with a lock that prevents water from entering to the switch contacts prevented; there are also holes to prevent water from accumulating inside the housing and thus prevent a possible short circuit of the switching contacts.

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Claims (5)

Expectations V _1- 1./Electric door switch, consisting of a housing with means for its attachment to a door frame, of a pair of switching contacts, one of which is movable and can assume a closed and an open contact position, and of one on the housing between a door Open position and a door closed position movably mounted trigger with a cam device which acts on the movable contact in the door closed position of the trigger and brings it into one of its two contact positions, while the movable contact is opposite to the other Contact assumes the other contact position when the release is in its door-open position, characterized in that the cam device (82) and the movable contact (38; 38a) are coordinated so that the cam device the movable contact on the first part of the actuation path of the trigger (62) in the direction of its door-open position in its door-G The closed position is moved into the one contact position, while the cam device continues to hold the movable contact (38; 38a) in this contact position over the entire course of the remaining trigger actuation travel into the door closed position; and that _# the cam means (82) in the door-open position of the trigger (62) with respect to the movable contact (38; 38a) is a distance which is overcome on the first actuating path when the trigger contacts the movable contact . 2. Door switch according to claim 1, characterized in that the movable contact (38? 38a) by an arcuate piece 209830/0725 (46) has legs (42, 44) connected to one another and angled to one another; and that the cam device (82) acts on the curved piece (46) on the movable contact (38; 38a). 3. Door switch according to claim 1 or 2, characterized in that the trigger (62) at least partially by a Opening (60) in the housing (18) protrudes; that between the opening (60) and the switch contact contact area a wall (56) is located in the housing (18); and that between the opening (60) and the wall (56) at least a drain opening (58) is arranged for liquid from the housing. 4. Door switch according to at least one of the preceding claims, characterized in that in the wall (56) a passage slot (57) for the movable contact (38; 38a) is arranged. 5. Door switch according to at least one of the preceding claims, characterized in that the cam device (82) a first surface portion (85), which first on the movable contact (38; 38a) acts, and has an adjacent second surface portion (87) which acts on the further actuating path on the movable contact; and that the first surface portion (85) has a smaller radius of curvature possesses as the second 'surface section. 209830/0725