Claims:We claim:

1. A modular fuse switch (100) comprising:
• a first cassette (90) and a second cassette (95), the cassettes (90, 95)
having a first supporting wall (72), a second supporting wall (74), a third supporting wall (76), a fourth supporting wall (78), a plurality of stacking male-female parts (80), a first locking wall (82), a second locking wall (84) and a third locking wall (86) configured thereon, the cassettes (90, 95) being identical in construction serve as any one of a housing and a cover;
• a first terminal unit (60) and a second terminal unit (65), the first
terminal unit (60) placed on a left side and the second terminal unit (65) placed on
a right side of any one of the cassettes (90 / 95) serving as the housing, the
terminal units (60, 65) having,
a fuse terminal/ fuse holder (52) placed in the third supporting wall
(76), the fuse terminal (52) having a spring (54) connected thereto,
a box clamp (56) placed in the fourth supporting wall (78), and
a termination screw (58) placed in the second supporting wall (74); and
• a knob (40) placed in the first supporting wall (72) of any one of the
cassettes (90 / 95) serving as the housing, the knob (40) capable of being locked
in any one of the first locking wall (82) and the second locking wall (84) depending on ‘ON’ and ‘OFF’ positions thereof;
• a fuse (30) adapted to insert into the knob (40) in ‘ON’ and ‘OFF’
conditions;
• a pair of din-clips (20), each din clip of the pair of din-clips (20) being
inserted in the third locking feature (86) of each cassette to hold the cassettes (90,
95) in a distribution block/panel with a din rail; and
• a plurality of rivets (10) passing from the plurality of stacking male-
female parts (80) on any one of the cassettes (90 / 95) being the housing into the plurality of stacking male-female parts (80) on any one of the cassettes (95 / 90) being the cover to connect / assemble the cassettes (90, 95) face to face thereby forming a single pole assembly of the modular fuse switch (100).

2. The modular fuse switch (100) as claimed in claim 1, wherein the knob
(40) is locked in the first locking wall (82) in the ‘ON’ position.

3. The modular fuse switch (100) as claimed in claim 1, wherein the knob
(40) is locked in the second locking wall (84) in the ‘OFF’ position.

, Description:Field of the invention

The present invention generally relates to a modular fuse switch/ fuse carrier / fuse holder and more particularly to a construction of a single pole assembly of the modular fuse switch using two identical housings.

Background of the invention

The modular fuse switches are used in commercial, distribution, domestic and building segments to provide electrical protection short-circuits and over-loads, isolation and switching under inductive or resistive loads. They connect and disconnect electrical circuit parts without load or at full load. They act like a switch in which a fuse forms the moving contact i.e. it is capable of making, carrying and breaking currents under normal circuit conditions and also carrying currents under specified abnormal circuit conditions such as those of over-load and short-circuits for a specified time. In general, all modular fuse switches consists of two different components: housing and a cover that suffer several limitations as listed below:

• Two different plastic molds are required to mold the housing and the cover that result in increased mold cost and reduced productivity.
• With two different cassettes, it is very difficult to commonize internal components like fuse terminals and fuse holder springs etc, with this the number of plastic molds, press tool as well as overall cost increases resulting in reduced productivity.
• To assemble these types of modular fuse switches, poka-yoke is needed and special instructions; otherwise there might be chances of wrong assembly.
Accordingly, there is a need of a modular fuse switch that overcomes the above mentioned drawbacks of the existing modular fuse switches.

Object of the invention

An object of the present invention is to use a common housing for both housing and cover in all modular fuse switches thereby reducing the number and the cost of plastic molds and thus reducing the overall cost of final product and increasing the productivity.

Summary of the invention

Accordingly, the present invention provides a modular fuse switch. The modular fuse switch comprises a first cassette, a second cassette, a first terminal unit, a second terminal unit, a knob, a fuse, a pair of din-clips and a plurality of rivets.

The cassettes includes a first supporting wall, a second supporting wall, a third supporting wall, a fourth supporting wall, a plurality of stacking male-female parts, a first locking wall, a second locking wall and a third locking wall configured thereon. The cassettes being identical in construction serve as any one of a housing and a cover.

The first terminal unit is placed on a left side and the second terminal unit is placed on a right side of any one of the cassettes serving as the housing. The terminal units include a fuse terminal/ fuse holder, a spring, a box clamp and a termination screw. The fuse terminal is placed in the third supporting wall. The fuse terminal includes the spring connected thereto. The box clamp is placed in the fourth supporting wall. The termination screw is placed in the second supporting wall.

The knob is placed in the first supporting wall of any one of the cassettes serving as the housing. The knob is capable of being locked in any one of the first locking wall and the second locking wall depending on ‘ON’ and ‘OFF’ positions thereof. The knob in the ‘ON’ position is locked in the first locking wall and in the ‘OFF’ position is locked in the second locking wall.

The fuse is adapted to insert into the knob in ON and OFF conditions. Each din clip of the pair of din-clips is inserted in the locking feature of each cassette to hold the cassettes in a distribution block/panel with a din rail.

The plurality of rivets is adapted for passing from the plurality of stacking male-
female parts on any one of the cassettes being the housing into the plurality of stacking male-female parts on any one of the cassettes being the cover to connect / assemble the cassettes face to face thereby forming a single pole assembly of the modular fuse switch.

Brief description of the drawings

Other features as well as the advantages of the invention will be clear from the following description.
In the appended drawings:
Figure 1 shows a general overall dimension of a single pole assembly of a modular fuse switch, in accordance with the present invention;

Figures 2 and 3 show exploded views of the single pole assembly of the modular fuse switch, in accordance with the present invention;

Figures 4 - 7 show an assembly view of the single pole assembly of the modular fuse switch, in accordance with the present invention;

Figure 8 shows the cassettes of the single pole assembly of the modular fuse switch, in accordance with the present invention;

Figure 9 shows the cross-sectional view of the modular fuse switch with the all assembled components, in accordance with the present invention;

Figure 10 shows terminal units of the single pole assembly of the modular fuse switch, in accordance with the present invention;

Figure 11 shows a knob of the single pole assembly of the modular fuse switch, in accordance with the present invention;

Figure 12 shows a fuse of the single pole assembly of the modular fuse switch, with in accordance the present invention; and

Figure 13 shows a din-clip of the single pole assembly of the modular fuse switch, in accordance with the present invention.

Detailed description of the invention

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiment.

The present invention provides a modular fuse switch. The construction of a single pole assembly of the modular fuse switch is carried out using two identical housings. Using a common housing for both housing and cover in all modular fuse switches reduces the number and cost of plastic molds and thus reduces the overall cost of final product and increasing the productivity.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures.

Referring to figures 1-13, a modular fuse switch (100) in accordance with the present invention is shown. In an embodiment, a single pole assembly of the modular fuse switch (100) (herein after ‘the switch (100)’) has a dimensions of width = 17.5 mm (1-Mod), height = 100.6 mm and depth = 61.2 mm as shown in figure 1. However, it is understood that the switch (100) can have varying dimensions and can be also constructed as a multiple pole assembly in various alternate embodiments thereof.

The switch (100) comprises a first cassette (90), a second cassette (95), a first terminal unit (60), a second terminal unit (65), a knob (40), a fuse (30), a pair of din-clips (20) and a plurality of rivets (10). The above mentioned components are assembled using any suitable means known in the art.

Both first cassette (90) and the second cassette (95) are identical in construction and includes a first supporting wall (72), a second supporting wall (74), a third supporting wall (76), a fourth supporting wall (78), a plurality of stacking male-female parts (80), a first locking wall (82), a second locking wall (84) and a third locking wall (86) configured thereon as shown in figure 8. The cassettes (90, 95) being identical in construction serve as any one of a housing and a cover. Thus, the switch (100) is constructed using two identical housings (90, 95). No need of poka-yoke in the cassette (90, 95) with the above mentioned parts/features (72-86). Due to similar features (72 - 86) on both cassette (90, 95), the components are assembled on any of the left or right cassette (90 / 95).

The first terminal unit (60) is placed on a left side of any one of the cassettes (90 / 95) serving as the housing. The second terminal unit (65) is placed on a right side of any one of the cassettes (90 / 95) serving as the housing and having that first terminal unit (60) placed on the left side thereof. The terminal units (60, 65) include a fuse terminal/ fuse holder (52), a spring (54), a box clamp (56) and a termination screw (58) configured thereon as shown in figure 10. Specifically, the fuse terminal/ fuse holder (52) is placed in the third supporting wall (76). The fuse terminal (52) includes the spring (54) connected thereto. The box clamp (56) is placed in the fourth supporting wall (78). The termination screw (58) is placed in the second supporting wall (74).

The knob (40) is placed in the first supporting wall (72) of any one of the cassettes (90 / 95) serving as the housing. The knob (40) is capable of being locked in any one of the first locking wall (82) and the second locking wall (84) depending on ‘ON’ and ‘OFF’ positions thereof. The knob (40) is locked in the first locking wall (82) in the ‘ON’ position. During overloads and short circuits there is possibility of excessive vibrations in the system, in such cases the knob locking wall (82) holds the knob (40) in ON-position only. The knob (40) is locked in the second locking wall (84) in the ‘OFF’ position to prevent the knob (40) from falling back to a normal position during maintenance to hold and replace fuses with ease. The knob (40) is adapted to hold the fuse (30) once inserted therein in both ON and OFF conditions as shown in figure 11.

The fuse (30) as shown in figure 12 is adapted to insert into the knob (40) in ON and OFF conditions. The pair of din-clip (10) (refer figure 13) is a din rail locker adapted to hold the product in distribution block/panel (not shown) with a din-rail (not shown). Specifically, each din clip of the pair of din-clips (20) is inserted in the locking feature (86) of each cassette to hold the cassettes (90, 95) in the distribution block/panel with the din rail.

The plurality of rivets (10) is adapted for passing from the plurality of stacking male-female parts (80) on any one of the cassettes (90 / 95) being the housing into the plurality of stacking male-female parts (80) on any one of the cassettes (95 / 90) being the cover to connect / assemble the cassettes (90, 95) face to face thereby forming a single pole assembly of the modular fuse switch (100).

Referring now to figures 4-7, an operation to form the single pole assembly of the switch (100) is illustrated in accordance with the present invention. The first terminal unit (60) is placed on a left side of any one of the cassette (90 / 95) that serve as the housing. Thereafter, the second terminal unit (65), then the knob (40) followed by the fuse (30) are placed in the same cassette (90 / 95) being the housing. The present invention allows either of the cassettes (90, 95) to be used as left and right housing. Thereafter, the other cassette (95 / 90) serving as the cover is placed on the top of the cassette (90 / 95) to form the assembled switch (100).

Advantages of the invention

1. The switch (100) uses a same cassette as housing and cover due to similar construction of the cassettes (90, 95) and thus the assembly is done on any of the cassettes serving as the housing.
2. Single plastic mold is required, by making the housing and the cover construction common. With this the number of components and thus overall cost of tooling reduces and productivity increases and hence the final product cost reduces. The simplified construction of the housing minimizes the use of side core in tool.
3. By making housing and cover common, some of the components like the fuse terminals (52), the springs (54) and the like are very easy to communize.
4. The switch (100) allows all components to be assembled with ease in a reduced time without any need of poka-yoke.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.