FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
"Mechanical Pencil"
APPLICANTS - NAME, ADDRESS & NATIONALITY:
Akhani Prashantkumar Kiritkumar, E-5, New Satadhar Apartment, Near C P Nagar Cross
Road, Ghatlodia Road, Ghatlodia, Ahmedabad-380061, Gujarat, India.
Email ID: pkakhani@gmail.com, Tel (M): +91-9033367810. Nationality: Indian.
Thakkar Arpit Chimanbhai, 1, Chamunda Nagar Society, Near College Road, Kandla
Highway, Radhanpur-385340, Gujarat, India.
Email ID: arpitcthakkar@gmail.com, Tel (M): +91-9979060890. Nationality: Indian.
Jenish Nileshbhai Patel, B-505, Silicon Valley, Opp. Siddhi-Vinayak Complex,
Shivaranjani Cross Road, Satellite, Ahmedabad-380015, Gujarat, India.
Email ID: ienishpatel 19@gmail.com, Tel (M): +91-9978803267. Nationality: Indian.
Pathak Manan Jayeshbhai, 214, Patelvas, Madalpur, Ellisbridge, Ahmedabad - 380006
Gujarat, India.
Email ID: mananpathak96@gmail.com. Tel (M): +91-9879714890. Nationality: Indian.

Mechanical Pencil
FIELD OF THE INVENTION:
The present invention relates to the writing or drawing instrument, particularly the mechanical or clutch pencil. Invention is about reducing the amount of lead wastage occurring in these pencils, thereby using the maximum amount of every lead.
BACKGROUND OF THE INVENTION:
There are many writing as well as drawing instruments which have been used in our day-to-day life as like a simple wooden pencil, mechanical or clutch pencil, propelling pencil and different varieties of pen and marker.
Pencil is the most widely used writing and drawing instrument. Specifically, a mechanical pencil is used in variety of fields due to its advantages over simple wooden pencil such as ease of use in terms of sharpening, comfortable grip and many more. Also a mechanical pencil has a variety of lead diameter according to the requirements which mostly ranges from 0.3 mm to 5.6 mm.
A common problem which most of mechanical and propelling pencils face is that they waste around 25% of a single graphite lead. While writing or drawing with such a mechanical pencil, when the lead length becomes shorter than the gripping range of pencil mechanism, the lead shrinks back in pencil. So a considerable amount of useful lead cannot be utilized.
The prior art searches in patent and non patent databases reveal number of mechanical and propelling pencils having different lead feeding mechanism. And we observed that this problem of lead wastage, as described in above paragraph, is found in most of the mechanical pencils. There are also some mechanical pencils, which have a type of lead feeding mechanism that is capable to reduce lead wastage compare to others.
Japanese Patent JP2004130765 aims at providing a knock-type mechanical pencil that can substantially eliminate the amount of waste of lead. According to its description, when lead becomes shorter and moves out from chuck, manually locking mechanism is used to lock the lead. When lead size decreases, one need to manually release the lock and then push the lead by knocking the new lead. Again manually lock the shorter lead and repeat this procedure to use the pencil. Thus, in this mechanism, the shorter lead can only be knocked when there is an extra lead present behind the shorter lead. Also we need to operate the manual locking mechanism at all time when required for knocking the lead.
Japanese Patent JP2002362089 has a locking section at the front as well as at the rear end of the slider. In this, the chuck is advanced and locks the slider, until the clamper comes in contact with the stepped part. Moreover, the slider and the guide cylinder are locked at the front side of the locking section of the slider and the guide cylinder. Furthermore, when the

chuck is retracted from the foremost advanced state, the locking section provided at the rear end of slider is locked. Thus, to become retractable, chuck is operated continuously.
Another Japanese Patent JP200234785 has a rear locking part, provided almost at the rear end of the slider and another locking part provided at the forward portion of lead case. The slider can move backward through an interlocking action between the chuck and slider. When the chuck advances, the lock is released and the slider advances with the further moment of the chuck. When the chuck proceeds farther extent and starts to move backwards, the locking part formed at the rear end and another locking part formed at the lead case are locked. The slider moves forward together with further advancement of the chuck and is retracted in conjunction with the chuck. The gripping portion of the chuck is configured to engage with the core at the front end of the hole of mouth portion.
However, in both these Japanese Patent JP2002362089 and JP200234785, since the structure is complicated, there is a problem that it is difficult to provide a low unit cost mechanical pencil. Also, since the tip is formed as a chuck, it is difficult to draw a line by applying it to a ruler.
Hence there are several patents which have relatively low lead waste but they have complicated mechanism and have high manufacturing cost and some required special conditions to reduce the lead wastage.
Unlike these, in the present invention, we have modified the lead feeding mechanism of mechanical pencil that is novel from all other inventions and capable to reduce the lead wastage. The modified mechanism is easy to manufacture and less costly than the available product.
SUMMARY OF THE INVENTION:
We have modified the lead feeding mechanism in the mechanical pencil that enables it to write with extremely short piece of lead and could preserve it well enough that the graphite lead would not slip in and/or out of the pencil.
In order to achieve our objectives, in our modified mechanism of mechanical pencil, an idle lead is placed inside lead casing tube and clutched into the chuck of feeding mechanism to transfer the forward motion of feeding mechanism to the working lead. The tiny lead gripper cum supporter, placed at the tip of arrow pointer, is capable to grip the working lead up to the end of arrow pointer and supports the working lead against writing force. So we can comfortably write with the lead until its length become equals to the length of this lead gripper cum supporter.
The present invention can reduce the wastage of lead, occurred due to improper design specification and the use of conventional mechanism, up to 6mm per use of a single lead which is only 10% of a 60mm lead.

OBJECTIVES OF THE INVENTION:
• The primary objective of the present invention is to provide a mechanical pencil that has ability to write with short piece of lead.
• It is equally important objective of the present invention to decrease wastage of lead in the mechanical/propelling pencil.
• It is equally important objective of the present invention to reduce the wastage of time that found in changing of consecutive lead in mechanical pencil.
• It is another objective of the present invention to provide cheap & reliable mechanical pencil.
• It is another objective of the present invention to decrease working cost mechanical pencil by reducing wastage of lead.
• It is yet another objective of the present invention to reduce the environment pollution occurred by wastage of graphite lead.
• It is another objective of the present invention to increase the overall productivity of lead utilization.
DESCRIPTION OF THE INVENTION:
Key Components of the Invention, as per serial numbers given in figure 1 and figure 2:
1. Clip Head
2. Outer Body Back Part
3. Outer Body Front Part
4. Gripper
5. Lead Cover Tube
6. Arrow Pointer
7. Lead Gripper cum Supporter
8. Eraser
9. Cap
10. Casing Tube
11. Idle Lead
12. Feed Mechanism (outer body)
13. Feed Mechanism (chuck)
14. Feed Mechanism (spring)
The present invention has two assembly lines. First Assembly Line, as shown in Figure 1, consists of: Clip Head (1), Outer Body Back Part (2), Outer Body Front Part (3), Gripper (4), Lead Cover Tube (5), Arrow Pointer (6), Lead Gripper cum Supporter (7) and Feed Mechanism(outer body) (12). Second Assembly Line, as shown in Figure 2, consists of: Eraser (8), Cap (9), Casing Tube (10), Idle Lead (11), Feed Mechanism (chuck) (13) and Feed Mechanism (spring) (14).
In first assembly line, Gripper (4) assembles with front part of outer body (3). Lead gripper cum supporter (7) assembles in the tip of arrow pointer (6). These both subassemblies join together through threads or any other means by placing lead cover tube (5) concentric inside

them. The front part (3) and back part (2) of outer body also join together by means of threads while clip head (1) is attached on other end of the back part of outer body (2).
In second assembly line, outer body of feed mechanism (12) is placed between the front part (3) and back part (2) of the outer body before they get assemble together. Chuck (13) is placed inside the outer body (12) of feed mechanism in such a way that its jaw-end remains towards the front side. Tail-end of the chuck (13) attaches with the small end of casing tube (10) by placing a spring (14) inside the outer body of feed mechanism (12). The subassembly of cap (9) and eraser (8) is attached with bigger end of the casing tube (10). The idle lead (11) is held inside the casing tube (10), keeping its head towards the cap (9), with the help of the jaws of the chuck (13) which is operated by spring force.
The lead gripper cum supporter (7), which is a short-tube type, slightly holds the working lead so that it will not be slip out from pencil. When we press the top (or say eraser (8)) of the pencil, the idle lead (11) slides into the chuck (13) and when we release the pressure, it holds inside the chuck (13) due to spring force.
When we push the top (or say eraser (8)) of the pencil, it moves the casing tube (10) inside the outer body (2) of feed mechanism which finally presses the chuck (13) against spring force. So the jaws of the chuck (13) will come out, holding the idle lead (11), from the outer body of feed mechanism (12) and it just pushes the idle lead (11) before release. Finally this forward motion of the idle lead (11) transmits to working lead and the working lead will move forward in the pencil.
Now when we release the pressure from the top of the pencil, the chuck (13) sets back in its original position due to spring force (14) and its jaws will squeeze inside the outer body of feed mechanism (12) and finally be tightened on the idle lead (11). Hence the Idle Lead (11) will get hold firmed. As the jaws tightened, they slightly pull the idle lead (11) backwards until they set to rest. So we notice that when we apply pressure on the spring (14), the chuck (13) pushes the idle lead (11) to a longer distance and when we release pressure, it pulls the idle lead (11) backwards to around half of the distance traveled during forward motion, leaving the remaining half out. As a result, we achieve a half forward motion of idle lead (11) which is finally transmitted to working lead.
Now the working lead cannot go backward due to support of the idle lead (11) on back and also it cannot slip out of the pencil body as the lead gripper cum supporter (7) holds it with some friction. Figure 3 shows the orthographic assembly drawing in three different views.
The mentioned invention may be embodied in modified form of idle lead (11) or/and lead gripper cum supporter (7) or carried out in other ways without departing from the spirit or essential characteristics thereof. The preferred embodiment mentioned above is therefore to be considered as in all respects illustrative and not restrictive. In other preferred embodiments, other lead feeding elements are incorporated into said mechanism to reduce lead wastage and provide simple and user-friendly mechanical pencil.

CLAIMS:
1. There are two assembly lines namely, First assembly line and Second assembly line: the first assembly line serves the purpose of supporting body whereas the second assembly line consists of working parts.
2. The first assembly line consists of Clip Head (1), Outer Body Back Part (2), Outer Body Front Part (3), Gripper (4), Lead Cover Tube (5), Arrow Pointer (6), Lead Gripper cum Supporter (7) and Outer body of feed mechanism (12), where Gripper (4) assembles with front part of outer body (3); Lead gripper cum supporter (7) is placed at the tip of arrow pointer (6); These both subassemblies join together through threads or other means by placing lead cover tube (5) concentric inside them; The front part (3) and back part (2) of outer body also join together; Clip head (1) attaches on other end of the back part of outer body (2).
3. The second assembly line consists of Eraser (8), Cap (9), Casing Tube (10), Idle Lead (11), Chuck (13) and Spring (14): outer body of feed mechanism (12) is placed between the front part (3) and back part (2) of the outer body before they assemble; Chuck (13) is placed inside the outer body (12) of feed mechanism by placing its jaw-end towards the front; Tail-end of the chuck (13) attaches with the small end of casing tube (10) by placing spring (14) between them; The subassembly of cap (9) and eraser (8) attaches with the bigger end of the casing tube (10); The idle lead (11) is placed inside the casing tube (10) by holding it within the jaws of chuck (13) while keeping its head towards the cap (9) of the pencil.
4. The lead gripper cum supporter (7), as mentioned in claim 2, resembles a short tube that slightly holds the working lead so that it will not slip out from pencil during both working and idle conditions.
5. The idle lead (11), as stated in claim 2, is held in chuck and pushes the actual lead out of lead gripper cum supporter (7), when pushed from the top (or say eraser (8)) of the pencil.