FIELD OF INVENTION
The present invention generally relates to a tool holding device. More particularly
the present invention relates to a tool holding device in a horizontal boring
machine adaptable to perform groove machining on vertical flange face.
BACKGROUND OF THE INVENTION
In a typical machine shop, horizontal boring machine plays an important role to
perform facing, boring, grooving and thread cutting (external/internal) operation
etc. In horizontal boring machine, the tool head is positioned in horizontal
position and the face of the component to be machined is kept vertical. Grooves
are normally cut on flange faces for proper insertion of sealing element namely
'U' ring etc. These grooves require a very smooth finish and tight dimensional
control. For machining grooves on a flange face using a horizontal boring
machine, the cutting tool is clamped on a tool bar. Boring head has movable
slides, and the movement of the slides is controlled via guide ways through
manually driven gear box.
Gear Box -> movable slide -> Tool Bar -> cutting tool
+ Guide way
<- Tool Head ->
When the tool starts a grooving operation, an opposite cutting force is generated
which creates a gap between the movable slide and the guide way. This gap
results into breakage of the tool tip and creates dimensional variation of the
groove which leads to frequent breakdown of the tool vis - a vis high machining
time.

Secondly, the dimensional variations on machining takes place due to high
vibrations caused by large overhang of the slide/tool. This also leads to
impregnation of tool marks on the groove surface.
Thirdly, the tool holder movement takes place directly through the gear box, as a
result of which the gear box sometimes gets jamed due to entry of small metal
chips in between the gear teeth. Such foreign materials lead to breakage of the
gear teeth owing to excessive pressure generation and causes damage to the
tool holder (cutting tool). All the deficiencies together result into poor surface
finish and improper dimensions.
Fourthly, deficiencies in grooves are removed by manual buffing which leads to
increase in cycle time, poor quality, low productivity and rework.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose a tool holding
device in a horizontal boring machine adaptable to perform groove machining in
vertical flange face, which eliminates the disadvantages of prior art.
Another object of the invention is to propose a tool holding device in a horizontal
boring machine adaptable to perform groove machining in vertical flange face,
which leads to reduction in operational cycle time.
Yet another object of the invention is to propose a tool holding device in a
horizontal boring machine adaptable to perform groove machining in vertical
flange face, which increases the productivity of the machine by eliminating
rework.

A further object of the invention is to propose a tool holding device in a
horizontal boring machine adaptable to perform groove machining in vertical
flange face, which generates better dimensional accuracy and finish of the
groove.
A still further object of the invention is to propose a tool holding device in a
horizontal boring machine adaptable to perform groove machining in vertical
flange face, which decreases power consumption.
Yet further object of the invention is to propose a tool holding device in a
horizontal boring machine adaptable to perform groove machining in vertical
flange face, which reduces the frequency of breakdown of the gear box.
SUMMARY OF THE INVENTION
To eliminate the problems of frequent breakage of gear box, increased vibration,
and creation of gap between the movable slides and the guide way during
groove cutting on horizontal boring machines, the invention provides a control
means to monitor and control the tool bar.
The control means has been configured to operate in two steps, for example,
Step 1 - the movables slide has been converted into a fixed slide (cassette) by
bolting it to the guide plate and thus eliminating the guide way altogether. The
cassette eliminates the gap generation between the tool bar and the movables
slide, which otherwise is creatable due to the cutting force. The tool bar is
caused to advance in response to the tightening of the bolts in the cassette
which in turn leads to tool movement. The invention further provides a lock

arrangement for the tool bar and bolt to avoid vibration. The maximum limit of
the tool bar movement is described in step II.
Step II - In order to overcome the problem of overhanging of the movable slide
and the tool bar, the movement of the tool bar is achieved by varying the
position of the cassette on a guide plate, thereby discarding the gear box
arrangement altogether. A number of bolting positions are provided on the
guide plate and the cassette is suitably attached on the bolting position of the
guide plate to achieve required positioning of the tool bar to ensure greater
rigidity.
Accordingly, there is provided a tool holding device in a horizontal boring
machine adaptable to perform groove machining in a vertical flange face
comprising a shank releasably attached and bolted to a guide plate in which a
cassette is mounted by means of at least one third bolt, the cassette provided
with a through hole for insertion of a tool bar from one end and a threaded part
provided on the other end for pushing out the tool bar in an outward direction by
means of a fourth bolt which is being locked by a lock nut, the tool bar is
tightened by a first bolt provided in the cassette, repositioning of the cassette is
achievable by setting it at one of the plurality holes provided at different
positions of the guide plate, and the tool bar holding a tool by means of a
second bolt at one end, the other end being inserted in the cassette .

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig.1 - shows a schematic diagram of machining of grooves on a vertical flange
face in the horizontal boring m/c according to prior art.
Fig.2 - shows a schematic diagram of a holding device in a horizontal boring
machine adaptable to perform groove machining according to the present
invention.
Fig.3 - shows a schematic diagram of the shank of fig. - 2.
Fig.4 - shows a schematic diagram of the cassette of fig. - 2.
Fig.5 - shows a schematic diagram of the guide plate of fig. - 2.
Fig.6 - shows schematic diagram of the tool bar of fig. - 2.
DETAILED DESCRIPTION OF A PREFERRED EMBODIEMNT OF THE
INVENTION
Fig.2 shows the device of the invention in the form of a boring head assembly to
ensure cutting of proper groove (17) on vertical flange face. Movement of the
tool bar (7) is controlled by a first bolt (3) which is provided in a cassette (4).
The tool bar (7) is movable corresponding to a tightening action of the first bolt
(3). A provision is made for taking out the cassette (4) from the existing position
and re-clamped by a third bolt (5) at a new location on the guide plate (2) to
achieve required cutting approach without having substantial overhanging.

Figs. 3,4,5,6 - show that the shank (1) is fixed to the guide plate (2) by using a
second bolt (6). The cassette (4) is attached to the guide plate (2) by using the
third bolt (5). The tool bar (7) is tightly fitted within the cassette (4) by using the
first bolt (3) for proper gripping.
The cassette (4) is provided with a through hole with its threaded portion at one
end. This threading is used to tighten a fourth bolt (8) which pushes the tool bar
(7) through the cassette (4). The tool bar (7) through the cassette (4) is push
fitted in a cassette hole. At least two first bolts (3) are provided for clamping. A
cutting tool (11) is mounted on the tool bar (7) by using a second bolt (10).
For movement of the cutting tool (11), with the tightening of the fourth bolt (8)
the tool bar (7) is pushed in an outward direction which in turn advances the
cutting tool (11). On reaching the right positing, the tightening bolt (8) is locked
by a locknut (9) and the first bolt (3) also locks the tool bar (7) in the cassette
(4). When a maximum limit of the tool bar (7) is reached during the machining
operation, the cassette (4) is immediately taken out from the guide plate (2) and
set in a new position and re-tightened using the third bolt (5) in the guide plate
(2). The tool bar (7) is further push fitted in the cassette (4) and groove cutting
operation restarted until it is completed.
Tightening Bolt -> Tool Bar -> Cutting Tool
Cassette + Guide Plate -> Tool Bar -> Cutting Tool
< TOOL Head >

WE CLAIM
1. A tool holding device in a horizontal boring machine adaptable to
perform groove machining in a vertical flange face comprising :
- a shank (1) releasably attached and bolted to a guide plate (2) in
which a cassette (4) is mounted by means of at least one third bolt
(5);
- the cassette (4) provided with a through hole for insertion of a tool
bar (7) from one end and a threaded part provided on the other
end for pushing out the tool bar (7) in an outward direction by
means of a fourth bolt (8) which is being locked by a lock nut (9),
the tool bar (7) being tightened by a first bolt (3) provided in the
cassette (4), a repositioning of the cassette (4) is achievable by
setting it at one of the plurality holes provided at different positions
of the guide plate (2); and
- the tool bar (7) holding a tool (11) by means of a second bolt (10)
at one end, the other end being inserted in the cassette (4).
2. The device as claimed in claim 1, wherein the shank (1) is fitted on the
horizontal boring machine.

3. The device as claimed in claim 1, wherein the shank (1) comprises a
plurality of clamping holes (6) matching with the holes of the guide
plate (2) for clamping the guide plate (2) by adapting fastening
means.
4. The device as claimed in claim 1, wherein the cassette (4) is provided
with a plurality of holes for clamping with the guide plate (2).
5. The device as claimed in claims 1 & 4, wherein positioning and
repositioning of the cassette (4) is done by resetting the clamp of the
cassette (4) at different holes disposed in the guide plate (2).
6. A tool holding device in horizontal boring machine adaptable to
perform groove machining in a vertical flange face as substantially
illustrated and described herein with reference to the accompanying
drawings.

ABSTRACT

TITLE : A TOOL HOLDING DEVICE IN A HORIZONTAL BORING
MACHINE ADAPTABLE TO PERFORM GROOVE MACHINING IN
A VERTICAL FLNAGE FACE.
This invention relates to a tool holding device in a horizontal boring
machine adaptable to perform groove machining in a vertical flange
face comprising a shank (1) releasably attached and bolted to a guide
plate (2) in which a cassette (4) is mounted by means of atleast one
third bolt (5), the cassette (4) provided with a through hole for
insertion of a tool bar (7) from one end and a threaded part provided
on the other end for pushing out the tool bar (7) in an outward
direction by means of a fourth bolt (8) which is being locked by a lock
nut (9), the tool bar (7) is tightened by a first bolt (3) provided in the
cassette, re-positioning of the cassette (4) is achievable by setting it at
one of the plurality holes provided at different positions of the guide
plate (2), the tool bar (7) holding a tool (11) by means of a second
bolt (10) at one end, the other end being inserted in the cassette (4).