Claims:We claim the following from our invention,

Claim:
1. A wire cut electrical discharge machine specimen holder comprising:
a) A specimen (3) was mounted firmly in between the cylindrical jaws (2 and 4) by a screw arrangement.
b) The screw arrangement was structurally supported by the flat and vertical plates (1 and 5)
c) The flat plates are capable to move along the groove direction with respect to the rotation of the screw arrangement.
2. As mentioned in claim 1, the cylindrical jaws are having slight curvature to hold the specimen rigidly. The curvature of the jaw can be varied depending upon the specimen dimension.
3. According to claim 1, curvature jaw is comprising v grooves to increase the grip between the specimen and jaw. , Description:Field of Invention
The present invention relates to, the specimen holder chuck that helps to hold the specimen while performing electrical discharge operation. By choosing the specimen holder with cylindrical jaws, it can hold even cylindrical shaped specimens with good grip.
The objectives of this invention
The objective of this invention is to improve the specimen stability in order to perform highly accurate precession-based cutting, by avoiding vibrations. The cylindrical chuck can increase the contact surface area of specimen with specimen holder.
Background of the invention
It was observed that EDM is one of the machining processes which can be performed with high accuracy to make cuts in curved shapes. The concept involved here is using electric voltage in machining process. High stress developed on the specimen where the cut is required with electric voltage supply. The specimen gets heated instantly and machining process is done.
The electric voltage generates when the specimen is in closed proximity with cutting wire. A recent invention explained about the importance of precision in Wire cutting EDM machining process. A strain gauge device is used to measure the deformation in wire holding arm due to high heat transfer in the process of machining with high voltage supply. This heat transfer will lead to thermal expansion in wire holding arm. Which can be avoided by using strain gauge, but we can further improve the precision by concentrating on the areas that are affecting the precision of machining process. (TWI395627B)
There will be a tool holder which holds the wire at different positions by maintaining required tension in the wire and another one is to hold the specimen. Here it is observed that the specimen holder has flat surface plates, which can hold flat sided specimens with good grip, but coming to the cylindrical shaped specimens, the grip was not up to the mark with normal loads. So, we have to apply more load to have good grip in holding cylindrical specimens, other wise there is chance of specimen rotation while performing EDM operation with high speed.
In this case more stress acts on the specimen while holding with flat plates. So, in order to avoid applying more loads, to decrease the stress on specimen we can use a cylindrical shaped chuck to hold the cylindrical shaped specimens. Observed this difference in testing specimens in UTM machine. While applying tensile loads on specimens to know the tensile strength, we use different jaws like flat plate jaws and cylindrical grooved jaws to have good grip, to avoid specimen slip from holder. This concept is implemented in the Wire cutting EDM machine to hold the cylindrical specimen
The wire cutting EDM uses liquid to control the heat transfer. The specimen is immersed in coolant liquid, and coolant is flushed with high pressure where the actual heat transfer control is required. In this process the specimen undergoes pressure loads due to supply of coolant. It is also important to hold the specimen with good grip to maintain precision in machining operation avoiding all these different loads acts on the specimen. (US9463520B2)

Summary of the invention
In light of the above mentioned drawbacks in the prior art, the present invention aims to hold the specimen rigidly irrespective of its shape and size.
With this specimen holder we can provide good grip, so that we can mitigate vibration at faster EDM operation, and accuracy of cut does not effect, at the same time EDM machining time will also decreases. Which ultimately increases the productivity in large scale Industrial applications.
Detailed description of the invention
The main aim of the invention is to increase the grip in holding the cylindrical specimens. The EDM process involves machining of specimen with high accuracy and precision.
The EDM performs machining operation by using electric power. The electric power is supplied to specimen and the cutting wire with help of holding arms. When the cutting wire comes near to the specimen high voltage transfer will occur, which results in high energy transfer through the contact between specimen and cutting wire. In this process high amount of heat energy is being released which results in melting the material in contact with the cutting wire, as cutting wire has more heat resistant than the specimen and machining of the material occurs.
In this machining process the released amount of heat will also transfer to the tool holding arm and specimen holder. In order to avoid heat transfer to the other regions of specimen and tool holding arm, the total setup is immersed in a coolant and coolant is impinged with high pressure to avoid heat transfer to the other parts of EDM setup.
In this process the specimen is subjected to high loads due to coolant flow impingement, so it required to hold the specimen with good grip so that it should not move while performing machining operation. Due to the high voltage transfer vibrations will also develop in the specimen, specimen holder is used to hold the specimen such that vibrations developed does not affect the position of specimen with respect to cutting wire. It is observed that flat surface plates are using to hold the specimens in Wire cutting EDM machines.
The specimens used in the EDM can have flat surfaces or curved surfaces too. When comparing flat surface specimen with curved surfaced specimens, the grip will be different as contact surface between flat surface plate and curved surface specimen. In order to over come this difference invention is made to maintain good grip even for curved surfaced specimens.
In this invention a design of cylindrical shaped surface specimen holder is made. cylindrical shaped surface specimen holder will consist two jaws, each jaw contains 4 sides and both are similar in geometrical and mechanical features. 3 sides of each jaw will have flat surface and the 4th side will be in curved shape with vertical V groves. The curved cylindrical shape on 4th side will have contact with specimen while holding it, this cylindrical shape 4th side of the specimen holder increase the contact area with the specimen while holding. The vertical ‘V’ groves will provide required roughness to increase the grip between specimen and specimen holder.
In this invention we add one cylindrical chuck which can be placed in between flat specimen holder of Wire cutting EDM machine. It is very easy to place the cylindrical chuck whenever we want. There is know need of any extra modifications to be done in the present wire cutting EDM machine specimen holder, only thing is we place cylindrical chuck in between flat specimen holder.
By using this cylindrical specimen holder, we can hold the specimen with good grip, by applying less load on specimen. The main advantage from this cylindrical chuck is, as it provides good grip to hold specimen, we can perform EDM operation faster as there is a very less chance to specimen to slip from the holder, because while perform faster EDM operations more loads and vibration may generate which decreases the accuracy of cut if the grip is not perfect.
This cylindrical specimen holder will increase the contact area with specimen compared the flat plate specimen holder and maintains good grip in holding the curved shape specimens.
Brief description of Drawing
In the figures which are illustrate exemplary embodiments of the invention.
Figure 1 Pictorial representation of the cylindrical specimen holder
Figure 2 Model of the cylindrical specimen holder jaw
Figure 3 Dimension of the cylindrical specimen holder jaw.
Detailed description of the drawing
As described above the present invention relates to optimizing the performance of wire cutting EDM specimen holder by increasing the surface contact of specimen holder and specimen with 2 cylindrical jaws. Each jaw is placed opposite sides of the specimen and in between the flat plate specimen holders.

Figure 1 shows the shows the arrangement order of cylindrical specimen holder in flat surface specimen holder.

Figure 2 showing the isometric view of a single jaw of specimen holder. Figure 2 is showing the key features of the invention. It is observed that the invention has 3 flat surfaces and 1 curved surface with vertical ‘V’ grooves. The total number grooves are 14 with equal spacing.

Figure 3 showing the dimensions of the features of the invention. All dimensions are in inches.
The main feature of invention curved surface has a radius of 25 inches. Length is 12 inch and width are 2 inches as shown in the figure 2.