阅读说明：本技术 电气开关 (Electrical switch ) 是由 黄美媚 于 2019-03-28 设计创作，主要内容包括：一种电气开关(100),其具有壳体(200),设置在壳体(200)中的多个固定触点(400)和至少一个移动触点(500),以及支撑在壳体(200)中的转子(300),其用于围绕旋转轴线(X)旋转,以使移动触点(500)与至少一个固定触点(400)接触或脱离接触,从而执行切换动作。还提供了用于旋转转子(300)的操作机构(600)。固定触点(400)相对于旋转轴线(X)布置在转子(300)的一侧。(An electrical switch (100) has a housing (200), a plurality of fixed contacts (400) and at least one moving contact (500) disposed in the housing (200), and a rotor (300) supported in the housing (200) for rotation about an axis of rotation (X) to bring the moving contact (500) into and out of contact with the at least one fixed contact (400) to perform a switching action. An operating mechanism (600) for rotating the rotor (300) is also provided. The fixed contact (400) is arranged on one side of the rotor (300) with respect to the rotation axis (X).)

1. An electrical switch, comprising:

a housing;

A plurality of fixed contacts and at least one moving contact disposed in the housing;

a rotor supported in the housing for rotational advancement about an axis of rotation to move the moving contact into and out of contact with at least one of the fixed contacts to perform a switching action; and

An operating mechanism for rotationally advancing the rotor;

wherein the fixed contact is arranged on one side of the rotor with respect to the rotation axis.

2. An electrical switch according to claim 1, wherein the fixed contacts are arranged in a row extending in a first direction substantially parallel to the axis of rotation.

3. The electrical switch of claim 2, wherein the fixed contacts are aligned with each other in the first direction.

4. The electrical switch of claim 2, wherein the fixed contacts are positioned at regular intervals along the first direction.

5. An electrical switch as in claim 1, wherein at least one of the stationary contacts is elongated and extends transverse to the axis of rotation.

6. The electrical switch of claim 5, wherein the at least one stationary contact has opposing first and second ends, and the stationary contact is supported at the first end for pivotal movement by the rotor at the second end.

7. An electrical switch according to claim 1, wherein the fixed contacts have substantially the same structure and are arranged in a regular manner.

8. An electrical switch according to claim 1, wherein said moving contact extends across all of said fixed contacts for performing switching actions with said fixed contacts at different times and/or in different combinations.

9. An electrical switch according to claim 1, wherein said moving contact is carried by and moves with said rotor, i.e. said moving contact is located on said rotor.

10. An electrical switch as in claim 9 wherein the rotor has a cavity in which the moving contact is located, the cavity having at least one open area through which the moving contact is exposed and contactable with an associated stationary contact.

11. An electrical switch according to claim 10, wherein said cavity comprises at least one enclosed area for covering and blocking said moving contact from contacting said associated stationary contact.

12. The electrical switch of claim 11, wherein the open area and the enclosed area associated with the same fixed contact together extend circumferentially relative to the rotor.

13. An electrical switch according to claim 12, wherein the open area and the closed area associated with each of the fixed contacts together extend circumferentially relative to the respective portion of the rotor and all of these portions are arranged in a row along the axis of rotation of the rotor, with the open areas being offset between adjacent portions.

14. An electrical switch according to claim 13, wherein the rotor comprises an annular flange extending between and separating adjacent open and/or closed regions.

15. An electrical switch according to claim 1, wherein the rotor includes at least one ramped projection for resisting rotational reversal by abutment of an associated fixed contact when the operating mechanism is released.

16. An electrical switch according to any of claims 11 to 14, wherein the rotor comprises at least one inclined projection for resisting rotation reversal upon release of the operating mechanism by abutment of an associated fixed contact, the inclined projection extending in the direction of the axis of rotation and on and along an edge of the enclosed area.

17. An electrical switch according to claim 9 or 15, wherein the cavity has an open end relative to the axis of rotation through which the moving contact is inserted into the cavity, whereby the moving contact is located in the cavity for rotation with the rotor about the axis of rotation.

18. An electrical switch according to claim 9 or 15, wherein the moving contact has a part-cylindrical body and is fixed to the rotor in a coaxial manner.

19. Electrical switch according to claim 18, characterized in that the part-cylindrical body has a cross-section extending around the rotor over an angle of 180 °, and preferably an angle of about 270 °.

20. An electrical switch according to claim 1, wherein the operating mechanism comprises ratchet means ratcheted with a rotor member of the rotor, a manually operable member for operating the ratchet means in a drive direction to advance the rotor, and first resilient means resiliently biasing the ratchet means to return in a non-drive direction opposite to the drive direction.

21. An electrical switch according to claim 20, wherein said ratchet means are supported for linear movement in opposite directions transverse to said axis of rotation.

22. An electrical switch according to claim 20 or 21 wherein the ratchet arrangement comprises a ratchet member arranged to engage the rotor member in the drive direction when operated by the manually operable member and to clear the rotor member in the non-drive direction under the action of the first resilient means.

23. an electrical switch according to claim 22, wherein the ratchet member is pivotable relative to the action of second resilient means to clear the rotor member in the non-driving direction.

24. An electrical switch according to claim 23, wherein said ratchet member comprises a rigid support providing rigidity for engaging said rotor member in said drive direction.

25. An electrical switch according to claim 20, wherein said rotor member includes an annular arrangement of projections on said rotor about said axis of rotation.

26. an electrical switch according to claim 25, wherein said rotor member is disposed at one end of said rotor.

27. an electrical switch according to claim 20, wherein said manually operable member comprises an elongate flexible member connected to said ratchet arrangement.

28. An electrical switch according to claim 27, wherein said elongated flexible member is releasably connected to said ratchet means at an engagement.

29. The electrical switch of claim 28, wherein said housing has an openable portion to expose said engagement portion for connecting or disconnecting said elongated flexible member.

30. An electrical switch as in claim 1 wherein said housing has a plurality of openings on opposite first and second sides thereof, wherein said manually operable member is exposed through one of said openings on said first side for user manipulation and a cable is insertable through the other of said openings on said second side for connection to said stationary contacts, respectively.

31. The electrical switch of claim 1, wherein the housing has a first compartment holding the fixed contact and the moving contact and a second compartment holding the operating mechanism.

32. The electrical switch of claim 31, wherein the first compartment is partitioned into separate spaces interconnected by a common area, wherein each space holds a respective fixed contact and the common area holds the rotor.

33. The electrical switch of claim 32, wherein said spaces are oval shaped and extend in a co-parallel manner.

34. The electrical switch of claim 32, wherein said spaces are of the same shape and size and are aligned with each other.

35. An electrical switch according to any of claims 31 to 34, wherein said housing has a first housing portion including said first and second compartments, and a second housing portion enclosed on said first housing portion, said first and second housing portions together forming said housing.

36. An electrical switch according to claim 35, wherein said second housing portion has an integrally connected tube through which said manually operable member extends out of said housing for manipulation by a user, said tube having external threads and being usable in cooperation with a nut having internal threads to mount the entire electrical switch to a component or housing of an electrical apparatus to control operation thereof.

Technical Field

The invention relates to an electrical switch comprising an inner rotor for switching.

Background

Such electrical switches are commonly referred to as rotary step switches. In a typical structure, a switch has a housing, a rotor, a moving contact mounted on the rotor, and a plurality of fixed contacts provided around the rotor for switching by contacting the moving contact when the rotor is rotated in a stepwise manner by pulling a chain or the like.

There are a number of problems with such switches. The arrangement of the fixed contacts around the rotor imposes restrictions on the design of the switch and in particular makes it difficult to change the number of fixed contacts or to mount more than four to five fixed contacts with respect to the design of the housing. By connecting to the switch in different directions around the circumference of the latter, the arrangement or running of the cable in narrow spaces is cumbersome.

The present invention aims to alleviate or at least alleviate the above problems or disadvantages by providing an improved or new electrical switch.

Disclosure of Invention

According to the present invention there is provided an electrical switch comprising a housing, a plurality of fixed contacts and at least one moving contact disposed in the housing, and a rotor supported in the housing for rotational advancement about a rotational axis to move the moving contact into and out of contact with the at least one fixed contact to perform a switching action. An operating mechanism for rotationally advancing the rotor is also provided. The fixed contact is arranged on one side of the rotor with respect to the rotation axis.

Preferably, the fixed contacts are arranged in a row extending in a first direction substantially parallel to the axis of rotation.

More preferably, the fixed contacts are aligned with each other in the first direction.

More preferably, the fixed contacts are positioned at regular intervals in the first direction.

Preferably, the at least one fixed contact is elongate and extends transversely to the axis of rotation.

It is further preferred that the at least one fixed contact has opposite first and second ends and is supported at the first end for pivotal movement by the rotor at the second end.

Advantageously, the fixed contacts have substantially the same structure and are arranged in a regular manner.

Preferably, the moving contacts extend across all of the fixed contacts for performing switching actions with the fixed contacts at different times and/or in different combinations.

In a preferred embodiment, the moving contact is carried by and moves with the rotor.

More preferably, the rotor has a cavity in which the moving contact is located, the cavity having at least one open area through which the moving contact is exposed and contactable with the associated stationary contact.

more preferably, the cavity comprises at least one closed area for covering and blocking the moving contact from contacting the associated fixed contact.

Still more preferably, the open area and the closed area associated with the same fixed contact extend together circumferentially with respect to the rotor.

Still more preferably, the open area associated with each fixed contact and the closed area together extend circumferentially relative to respective portions of the rotor and all of these portions are arranged in a row along the axis of rotation of the rotor with the open areas being offset between adjacent portions.

Still more preferably, the rotor comprises an annular flange extending between and separating adjacent open and/or closed regions.

preferably, the rotor includes at least one inclined projection for resisting rotation reversal by abutment of an associated fixed contact when said operating mechanism is released.

Preferably, the rotor comprises at least one inclined projection for resisting reversal of rotation upon release of said operating mechanism by abutment of the associated fixed contact, the inclined projection extending in the direction of the axis of rotation and along the edge of the enclosed area.

preferably, the cavity has an open end relative to the axis of rotation through which the moving contact is inserted into the cavity, whereby the moving contact is located in the cavity to rotate with the rotor about the axis of rotation.

Preferably, the moving contact has a part-cylindrical body and is fixed to the rotor in a coaxial manner.

It is further preferred that the part-cylindrical body has a cross-section extending around the rotor over an angle of 180 deg., and preferably an angle of about 270 deg..

In a preferred embodiment, the operating mechanism comprises ratchet means ratcheted with a rotor component of the rotor, a manually operable member for operating the ratchet means in a drive direction to advance the rotor, and first resilient means resiliently biasing the ratchet means to return in a non-drive direction opposite to the drive direction.

More preferably, the ratchet means is supported for linear movement in opposite directions transverse to the axis of rotation.

More preferably, the ratchet arrangement comprises a ratchet member arranged to engage the rotor component in the drive direction when operated by the manually operable member and to clear the rotor component in the non-drive direction under the action of the first resilient means.

Further more preferably, the ratchet member is pivotable against the action of the second resilient means to clear the rotor member in the non-driving direction.

Still more preferably, the ratchet member comprises a rigid support for rigidity when the ratchet member engages the rotor component in the drive direction.

In a particular arrangement, the rotor component comprises an annular arrangement of projections on the rotor about the axis of rotation.

More specifically, the rotor part is arranged at one end of the rotor.

Preferably, the manually operable member comprises an elongate flexible member connected to the ratchet means, the elongate flexible member being in the form of a bead or chain.

It is further preferred that the elongate flexible member is releasably connected to the ratchet device at the junction.

It is further preferred that the housing has an openable portion to expose a joint for connecting or disconnecting the elongate flexible member.

In a preferred arrangement, the housing has a plurality of openings on opposite first and second sides thereof, wherein the manually operable member is exposed through one of the openings on the first side for manipulation by a user, and the electrical cable is insertable through the other opening on the second side for connection to the fixed contacts, respectively.

In a preferred embodiment, the housing has a first compartment holding the fixed and moving contacts and a second compartment holding the operating mechanism.

More preferably, the first compartment is divided into separate spaces interconnected by a common area, wherein each space holds a respective fixed contact and the common area holds the rotor.

Even more preferably, the spaces are oval shaped and extend in a co-parallel manner.

Even more preferably, the spaces are of the same shape and size and are aligned with each other.

In a particular construction, the housing has a first housing portion including a first compartment and a second compartment, and a second housing portion enclosed on the first housing portion, which together form the housing.

More specifically, the second housing portion has an integrally connected tube through which the manually operable member extends out of the housing for manipulation by a user, the tube having external threads and being usable in cooperation with a nut having internal threads to mount the entire electrical switch to a component or housing of the electrical device to control operation thereof.

Drawings

The present invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a front perspective view of a first embodiment of an electrical switch according to the present invention;

FIG. 2 is a rear perspective view of the electrical switch of FIG. 1;

FIG. 3 is an exploded perspective view of the electrical switch of FIGS. 1 and 2, showing all of its internal components;

Fig. 4A-4C are perspective views of the rotor and moving contacts of the electrical switch of fig. 3, showing how the moving contacts mate with the rotor;

FIG. 5 is a schematic development of the rotor surface of FIGS. 4A-4C;

Fig. 6A, 7A, 8A and 9A are perspective views of the rotor with the moving contacts of fig. 4A-4C and the four fixed contacts of fig. 3, showing four switching positions;

FIG. 6B, FIG. 7B, FIG. 8B and FIG. 9B are schematic circuit diagrams representing the switching positions of FIG. 6A, FIG. 7A, FIG. 8A and FIG. 9A, respectively;

10A-10F are cross-sectional side views of the electrical switch of FIGS. 1 and 2 showing sequential steps of the switching action;

Fig. 11 is a front perspective view of a second embodiment of an electrical switch according to the present invention;

Fig. 12 is a rear perspective view of the electrical switch of fig. 1; and

Fig. 13 is an exploded perspective view of the electrical switch of fig. 11 and 12, showing all of the internal components thereof.

Detailed Description

Referring initially to fig. 1 to 10 of the drawings, there is shown a first electrical switch embodying the present invention in the form of a step switch 100, the step switch 100 being operated by a beaded metallic zipper 90 or cord or any suitable elongate flexible member, also commonly referred to as a zipper switch. The electrical switch 100 has a housing 200, a plurality of (e.g., four) fixed contacts 400 and at least one (e.g., one) moving contact 500, all disposed in the housing 200. The electrical switch 100 comprises a rotor 300, the rotor 300 being supported in the housing 100 for rotation, in particular rotational advancement, about a rotation axis X to move the moving contact 500 into or out of contact with at least one of the fixed contacts 400 (for example all four fixed contacts 400) to perform a switching action. Also housed in the housing 200 is an operating mechanism 600 for rotating (i.e., advancing the rotor 300).

The fixed contact 400 is arranged on one single side (e.g., the lower side in fig. 3) of the rotor 300 with respect to the rotation axis X. The fixed contacts 400 are arranged in one single row extending substantially parallel to the rotation axis X in the first direction Y. The fixed contacts 400 are aligned with each other and positioned at regular intervals in the first direction Y.

At least one (e.g., each) of the fixed contacts 400 is elongated and extends transverse to the rotational axis X. Each fixed contact 400 has opposite first and second ends 401, 402 and is supported at the first end 401 for pivotal movement at the second end 402 by the rotor 300, similar to a lever. The fixed contacts 400 have substantially the same structure and are arranged in a regular manner, for example, end-to-end at regular intervals and in alignment with each other.

In operation, the fixed contact 400 bears with its second end 402 on the rotor 300 and/or on the moving contact 500 supported by the rotor 300.

The rotor 300 has a generally cylindrical body 309 having opposite first and second ends 310, 320 and a central axis coincident with the axis of rotation X. The rotor body 309 is formed with a part-cylindrical cavity 330 which shares the same central axis as the rotor body 309, or is coaxial about the central axis. The cavity 330 is formed at a small depth below the outer surface of the rotor body 309, has an open end 331 at the second end 320 of the rotor relative to the central axis, and extends around the central axis at an angle of about 270 °.

The moving contact 500 is carried by the rotor 300 and is located on the rotor 300 so as to move (i.e., rotate) with the rotor 300. The moving contact 500 has a part-cylindrical body 509 with a cross-section extending around the rotor 300 over an angle of approximately 270 deg., or in different embodiments over substantially 180 deg., for circuit connection. As shown in fig. 4A, the moving contact 500 is inserted into the cavity 330 of the rotor body 309 in the axial direction via the open end 331 of the cavity. The cavity 330 is made to match and fix the moving contact 500 therein such that the moving contact 500 is coaxially fixed in the cavity 330 to rotate together with the rotor 300 around the rotation axis.

The rotor body 309 is integrally formed with a series of three annular flanges 306 regularly spaced along the central axis, thereby dividing the rotor body 309 into four portions 301, 302, 303 and 304 in a row. The cylindrical surface of each section is divided into four equal regions A, B, C and D. When viewed in schematic development, the entire cylindrical surface of the rotor body 309 is divided into sixteen (16) regions 305 arranged in a 4 × 4 array (fig. 6).

As shown in fig. 6, the areas 305, that is, 301A to 301D, 302A to 302D, 303A to 303D, and 304A to 304D, can be individually identified by combining the relevant reference numerals in the XY coordinate number format. Six of these regions 305 (i.e., regions 301A-301C, 302A, 303B and 304C), collectively referred to as 305a, are open to expose corresponding regions of the moving contact 500 embedded in the rotor 300 for contact with the stationary contact 400 associated/aligned with the associated portion 301 and 304 of the rotor 300. The other areas 301D, 302B-302D, 303A, 303C, 303D, 304A, 304B and 304D, collectively referred to as 305B, are complete (i.e., closed) to cover the corresponding areas of the moving contact 500 or to prevent their contact by the associated/aligned fixed contacts 400.

The four sections a-D are arranged in a row along the rotational axis X of the rotor with the open areas 305a being offset between adjacent sections. Each flange 306 extends between and separates open and/or enclosed areas 305b between adjacent sections.

Four fixed contacts 400 are arranged to extend side by side on one side of and in alignment with respective portions a-D of the rotor 300, with their free ends 402 being resiliently biased against the respective portions a-D. In each section a-D there is at least one open area 305a exposing the moving contact 500 and at least one closed area 305b covering the moving contact 500, which together extend circumferentially around the rotor 300 to make or break contact, i.e. a switching action, with the same associated fixed contact 400. The moving contacts 500 extend across all fixed contacts 400 to perform switching actions on them at different times and/or in different combinations depending on how the open area 305a and the closed area 305b are arranged in each part of the associated fixed contact 400.

The rotor 300 includes at least one inclined projection or tooth 340 for resisting rotation reversal by abutment of the associated stationary contact 400 when the operating mechanism 600 is released. The inclined teeth 340 have a cross section of an inclined triangle rising from the surface of the rotor 300, and extend laterally in the direction of the rotation axis X. More specifically, the sloped teeth 340 extend over and along the edge of the enclosed area 305 b. The inclined teeth 340 are inclined or skewed in a direction opposite to the rotation direction Z of the rotor 300 to cancel the rotation thereof.

Typically, each portion of the rotor 300 is formed with at least one such slanted tooth 340 for cooperating with an aligned fixed contact 400. In the illustrated embodiment, there is typically one skewed tooth 340 per enclosed area 305b, and thus the second through third rotor portions 302-304 each have three skewed teeth 340. However, the remaining first rotor portion 301 has two inclined teeth 340, one along each opposing edge of the only enclosed region 305 b.

Referring to the housing 200, it has a first main housing portion 210 and a second sub-housing portion 220 which are closed on the main housing portion 210 and snap-fit with the main housing portion 210 to form the housing 200 together. The main housing portion 210 is divided into a large first compartment 211 holding the fixed contacts 400 and the moving contacts 500, and an elongated second compartment 212 holding the operating mechanism 600. The two compartments 211 and 212 are located next to each other.

The secondary housing portion 220 includes an integrally connected tube 221 through which the zipper 90 (i.e., the manually operable member 620) extends out of the housing 200 for manipulation by a user. The tube 221 is externally threaded and may be used in conjunction with a nut (not shown) having internal threads to mount the entire electrical switch 100 to a component or housing of an electrical device to control its operation.

The housing 200 has a plurality of (e.g., five) openings (holes) 201 and 204 on opposite first and second sides thereof. One of the openings (i.e., opening 201) is located on a first side corresponding to the sub-housing portion 220, with the manually operable member 620 being exposed through the opening 201 for manipulation by a user. The other four openings 204 are located on the second side corresponding to the main housing portion 210, and cables (not shown) can be inserted through the openings 204 to be connected to the fixed contacts 400, respectively.

Within the main housing portion 210, the first compartment 211 is divided into four separate spaces 214 interconnected by a common area 215. The space 214 is made oval and narrow in shape and extends in a common parallel arrangement and also parallel to the second compartment 212 of the partition. The spaces 214 are substantially the same shape and size and are aligned with each other. Each space 214 holds a corresponding fixed contact 400, which extends parallel to the space 214 and is inserted therein from the inside.

The common region 215 extends transversely across the inner open end of the space 214 and is larger and accommodates the rotor 300 with the moving contact 500. The common area 215 is taken at right angles to the second compartment 212, wherein the first end 310 of the rotor 300 is located within the second compartment 212.

Turning now to the operating mechanism 600, it comprises a ratchet arrangement 610 in ratchet engagement with the rotor part 311 of the rotor 300, and a manually operable member 620 for operating the ratchet arrangement 610 in the drive direction Z to rotate the rotor 300. The rotor part 311 comprises four radial protrusions or prongs 311 arranged annularly around the rotation axis X on the first end 310 of the rotor 300. The adjacent prongs 311 subtend an angle of 90.

The operating mechanism 600 further comprises first resilient means in the form of, for example, a compression coil spring 630 which resiliently biases the ratchet means 610 to return in a non-driving direction Z' opposite to the driving direction Z. The manually operable member 620 is the zipper 90 described above, the inner end of which is connected to the ratchet means 610 for pulling the ratchet means 610 against the action of the spring 630.

the ratchet means 610 is realized by a ratchet member in the form of a resilient hook-like pawl 611, which is located in a block 612, which block 612 is in turn supported in the second compartment 212 of the main housing portion 210 for linear sliding movement. The pawl 611 is bent forwardly and upwardly at an angle of about 45 deg.. The pawl 611 can pivot or bend downwards against the action of its own resilience (i.e. the second resilient means of the operating mechanism 600) but is blocked against pivoting upwards by a pair of hook-shaped prongs 613 covering its rear. The pawl 611 and fork 613 are integral components of the block 612.

the block 612 with the pawl 611 is slidable in opposite directions of the longitudinal extent of the second compartment 212, transversely to the rotor 300 or the axis of rotation X thereof. The block 612 with the pawl 611 is resiliently biased by a spring 630 to remain generally innermost of the second compartment 212, in this position of the pawl 611 with the adjacent prong 311 in the path of the tip forward of the tip of the pawl 611 (fig. 10A).

When the zipper 620 is pulled, the block 612 is pulled to slide it forward in the driving direction Z, wherein immediately after the pawl 611 abuts and pushes the prong 311 (fig. 10B), and then advances the rotor 300 by an angle of 90 ° (fig. 10C to 10D).

the ratchet member 610 comprises hook-shaped prongs 613 covering the rear of the pawl 611, the hook-shaped prongs 613 serving as a rigid support providing rigidity when the pawl 611 acts on the rotor tip 311 in the driving direction Z.

Upon release of the zipper 620, the spring 630 urges the block 612 to slide it rearward in the non-driving direction Z', wherein immediately following the pawl 611, the pawl 611 clears the next turned prong 311a (fig. 10E-10F) when the rotor 300 is prevented from counter-rotating by some of the ramped teeth 340 abutting its associated respective fixed contact 400.

The next prong 311a now replaces the first mentioned prong 311 for repeating the action of the pawl 611 when the zipper 620 is pulled to perform the next switching action.

the step switch 100 performs the switching action while repeatedly pulling the slide fastener 620 in a cyclic manner through the four switching positions, as shown in fig. 6A-6B, 7A-7B, 8A-8B, and 9A-9B. In these figures, the fixed contacts 400 are designated as "0", "1", "2", and "3", respectively, from the first portion 301 at the first end 310 to the rearmost portion 304 at the second end 320 of the rotor 300.

The fixed contact "0" acts as a knife, so the associated rotor portion 301 has only one closed area 305b, which corresponds to the off position. Thus, in fig. 9A-9B, none of the throws "1" through "3" are connected to the pole "0".

The other three fixed contacts "1", "2" and "3" serve as three throws to which a pole can be selectively connected, so the associated rotor portion 301 to 303 has only one open area 305a corresponding to the switching position of each throw connected to a pole. Thus, throw "1" is connected to pole "0" in FIGS. 6A-6B, throw "2" is connected to pole "0" in FIGS. 7A-8B, and throw "3" is connected to pole "0" in FIGS. 8A-8B, with the associated contact in the connection highlighted in gray.

This is the single pole, triple throw switch design of the step switch 100. The switch design is dictated by the design arrangement, particularly the arrangement of the open area 305a and the closed area 305b on the rotor 300, for exposing the desired area of the moving contact 500 for contact with the respective fixed contact 400 at each of the four angular positions (90 ° apart) of the rotor 300.

The zipper 620 is releasably connected to the block 612 at a joint 614, the joint 614 being the forwardmost end of the block 612. At this joint 614 is formed a socket 614a which receives and thus engages the innermost bead of the zipper 620. The block 612 is completely hidden within the housing 200, even when the zipper 620 is pulled out, the engagement 614 is within the tube 221 of the housing. To show the joint 614 for connecting or disconnecting the zipper 620, the case 200 has a wall portion immediately adjacent the joint 614, which is made openable (fig. 3), which is normally closed by a small lid 222 of the same shape and snapped into place.

Referring now to fig. 11-13 of the drawings, there is shown a second electrical switch embodying the present invention which is a step switch 900, very similar to the first electrical switch 100 described above, having almost the same structure and operation. Like parts are indicated by like reference numerals preceded by a prime.

The only major difference is that only two fixed contacts 400 'are used instead of four, with corresponding changes in the design of the rotor 400', the moving contact 500 'and the housing 200'. The rotor 300 'and the moving contact 500' are shorter, the former having only two portions 301 'and 302'. The housing 200 ' is also shorter in the direction through the fixed contact 400 ', comprising only two spaces 214 '.

All other components are identical to those in the first electrical switch 100, except for the above-mentioned components, i.e., the housing 200 ', the rotor 300 ' and the moving contact 500 '. Thus, these components can be shared for manufacturing the same type of electrical switch, thereby saving significant production costs and inventory control.

It should be noted that the design in which the cables may all be connected to the fixed contacts 400 via the openings 204 on one side of the housing 200, while the zipper 90/620 is provided on the opposite side, allows the electrical switch 100 to be placed in a relatively narrow space in an electrical device. This design also allows the cable to extend distally or inwardly without the need to rotate or bend around the housing 200, thereby simplifying cable travel.

the invention has been given by way of example only, and various modifications and/or changes to the described embodiments may be made by persons skilled in the art without departing from the scope of the invention as defined in the appended claims.