CA2488743A1 - Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) - Google Patents
Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) Download PDFInfo
- Publication number
- CA2488743A1 CA2488743A1 CA 2488743 CA2488743A CA2488743A1 CA 2488743 A1 CA2488743 A1 CA 2488743A1 CA 2488743 CA2488743 CA 2488743 CA 2488743 A CA2488743 A CA 2488743A CA 2488743 A1 CA2488743 A1 CA 2488743A1
- Authority
- CA
- Canada
- Prior art keywords
- self
- tool
- centering
- balls
- adjusting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B31/00—Chucks; Expansion mandrels; Adaptations thereof for remote control
- B23B31/02—Chucks
- B23B31/10—Chucks characterised by the retaining or gripping devices or their immediate operating means
- B23B31/12—Chucks with simultaneously-acting jaws, whether or not also individually adjustable
- B23B31/22—Jaws in the form of balls
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B31/00—Chucks; Expansion mandrels; Adaptations thereof for remote control
- B23B31/008—Chucks; Expansion mandrels; Adaptations thereof for remote control with arrangements for transmitting torque
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B2226/00—Materials of tools or workpieces not comprising a metal
- B23B2226/33—Elastomers, e.g. rubber
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Gripping On Spindles (AREA)
- Clamps And Clips (AREA)
Abstract
The invention is a high precision tool holder and clamping system, where base centering and holding of tools is realized by using a special Multi Ball Self-adjusting Self-centering Insert (MBSSI). This insert consists of high precision balls assembled in a specific order (in staggered rows) and held together as one unit by using an elastic substance or a special separator. The balls are arranged in a position of stable equilibrium and have permanent contact with each other. Due to that, the system is statically determinate and has a very high precision.
Multi Ball Self-adjusting Self-centering Insert (MBSSI) provides uniform distribution of base points on a tool surface (a-spot) with full force closure. Due to that, the Multi Ball Self-adjusting Self-centering Tool Holder (MBSSTH) and Mufti Ball Self-adjusting Self-centering Clamping System (MBSSCS) achieve very high rigidity.
Multi Ball Self-adjusting Self-centering Insert (MBSSI) provides uniform distribution of base points on a tool surface (a-spot) with full force closure. Due to that, the Multi Ball Self-adjusting Self-centering Tool Holder (MBSSTH) and Mufti Ball Self-adjusting Self-centering Clamping System (MBSSCS) achieve very high rigidity.
Description
DESCRIPTION OF THE INVENTION.
MULTI BALL SELF-ADJUSTING SELF-CENTERING TOOL HOLDER (MBSSTH) and MULTI BALL SELF- ADJUSTING SELF-CENTERING CLAMPING SYSTEM (MBSSCS).
FIELD OF THE INVENTION.
The present invention relates generally to tool holding systems for machine tools, more specifically, to a universal tool holder assembly that is used to center and hold a range of cutting tools, such as drill bits, reamers, and mills.
This invention is based on the following principals:
1. Ball self adjustment inside a closed space 2. Statically determinate system 3. Principal of equal distribution of base points uniformly on a tool surface (a-spot) 4. Principal of a full force closure 5. Principal of independently centering every layer of balls along the spindle's axis The name for the new Tool Holder is Multi Ball Self adjusting Self centering Tool Holder (MBSSTH). The name for the new clamping system is Multi BaII Self adjusting Self centering Clamping System (MBSSCS). It is based on the same principles as MBSSTH; the only difference is that this clamping system can be used in any application where coaxial centering and holding of two parts is needed.
The main goal of any tool holder is to hold the tools as precisely as possible, providing centering accuracy (where the tool axis coincides with the axis of a spindle of a Machine Tool), and holding the tools with high rigidity during machining operations. In modern time, manufacturing industry progressively uses aluminium alloys. Aluminum is machined at very high speeds (RPMs -revolution per minute). In order to perform accurate machining, it is especially important for the tool to stay rigid and maintain very high precision at high speeds. Today, usual machining speeds range q, - I5 between 10,000 to 20,000 RPM. Not many kinds of tool holders can handle such high RPMs without losing precision and rigidity.
A more traditional tool holder assembly (US Patent No 5,201,620) uses an external collet system (Fig. 1 and 2). In a traditional tool holder assembly, the axial movement of the conical collet causes the Inside Diameter of the collet to decrease due to its resiliency. This accomplishes the locking of the tool.
'The centering accuracy in such tool holder depends on the geometric precision of every element of the tool holder assembly and the tool itself. The top picture in Fig. 2 shows just a theoretical case, where it is impossible to provide full conformity of external base conical surface of the collet (EX), with internal base conical surface of the tool holder's body (BIN), simultaneously with conformity of internal cylindrical base surface of the collet (IN), with cylindrical base surface of the tool (T).
Any kind of precision has a tolerance. As a result, when the tool is locked, it is locked only on one side of the collet. However, on the other side of the tool, micro clearances remain.
Therefore, the Tool Axis (TA) of the locked tool ends up in some indeterminate position inside the micro tapered angle (G).
The same happens in the plane perpendicular to the tool axis. The size (H), of all petals of a collet, slightly differs from one another due to machining tolerances. As a result, the appearance of micro clearance (C1) or (C2) occurs.
Theoretically, any solid body has 6 possible movements: translation along three axes X, Y, Z and rotation around the same three axes. To eliminate all 6 possible movements, 4 contact points and clamping forces are needed. This condition provides a determinate position for any solid body.
This theoretical statement is true in practice for a traditional collet. The contact between the tool, the petals of the collet and the tool holder, is possible by three petals on one side and only one petal on the other side. These 4 points (a-spot) are theoretically possible for traditional tool holder assembly, Fig. 2.
As we can see, even in static state, the tool is clamped just on one of the sides of the collet along its axis, and only three petals are in contact with the tool. This causes the tool to lock in some indeterminate position inside the micro tapered angle (G), thus the tool cannot coincide with the base surface of the tool holder body and spindle of a machine tool. The presence of micro clearances and imprecise positioning of the tool inside the micro tapered angle (G) is especially noticeable at high RPMs. In places where micro clearances exist, the collet expands due to the centrifugal forces, causing the tool to distort and thus creating even greater inaccuracy and vibrations.
Due to the fact that a traditional collet has only 4 contact points, the contact surface area with a tool is very small. Sometimes because of that, the tool slips inside the tool holder at higher torque caused by cutting forces. A slipped bit completely loses its setting position inside the tool holder.
The presented invention, Multi Ball Self adjusting Self-centering Tool Holder (MBSSTH), completely solves all of these problems.
All described above is rightly for positioning the Tool Holder itself inside the nest of a spindle of machine tool. The Multi Ball Self adjusting Self centering Clamping System (MBSSCS) can be used for positioning the Tool Holder itself inside the Spindle of machine tool. MBSSCS can be used even to directly position the Tool inside the Spindle of Machine Tool. In that case, some of the inaccuracies of the tool setting assemblies can be completely eliminated.
SUMMARY OF THE INVENTION
The most essential goal of current invention is to improve universal tool holding system:
~ Significantly increase accuracy of the tool holder especially at high RPM.
~ Significantly increase rigidity of tool holders.
~ Create a Universal Tool Holding system for different applications.
~ Reduce accuracy requirements of tool's base surface. Accuracy requirement is run-out only.
~ Increase the ability of the tool holder to work with wider range of tool diameters.
~ Improve tool-setting procedures.
~ Significantly increase accuracy of positioning the tool holder inside spindle of machine tool.
~ Creating a system where the tool is seated directly into the spindle of machine tool, and eliminating the whole bunch of inaccuracies inside the tool setting assemblies.
MULTI BALL SELF-ADJUSTING SELF-CENTERING TOOL HOLDER (MBSSTH) and MULTI BALL SELF- ADJUSTING SELF-CENTERING CLAMPING SYSTEM (MBSSCS).
FIELD OF THE INVENTION.
The present invention relates generally to tool holding systems for machine tools, more specifically, to a universal tool holder assembly that is used to center and hold a range of cutting tools, such as drill bits, reamers, and mills.
This invention is based on the following principals:
1. Ball self adjustment inside a closed space 2. Statically determinate system 3. Principal of equal distribution of base points uniformly on a tool surface (a-spot) 4. Principal of a full force closure 5. Principal of independently centering every layer of balls along the spindle's axis The name for the new Tool Holder is Multi Ball Self adjusting Self centering Tool Holder (MBSSTH). The name for the new clamping system is Multi BaII Self adjusting Self centering Clamping System (MBSSCS). It is based on the same principles as MBSSTH; the only difference is that this clamping system can be used in any application where coaxial centering and holding of two parts is needed.
The main goal of any tool holder is to hold the tools as precisely as possible, providing centering accuracy (where the tool axis coincides with the axis of a spindle of a Machine Tool), and holding the tools with high rigidity during machining operations. In modern time, manufacturing industry progressively uses aluminium alloys. Aluminum is machined at very high speeds (RPMs -revolution per minute). In order to perform accurate machining, it is especially important for the tool to stay rigid and maintain very high precision at high speeds. Today, usual machining speeds range q, - I5 between 10,000 to 20,000 RPM. Not many kinds of tool holders can handle such high RPMs without losing precision and rigidity.
A more traditional tool holder assembly (US Patent No 5,201,620) uses an external collet system (Fig. 1 and 2). In a traditional tool holder assembly, the axial movement of the conical collet causes the Inside Diameter of the collet to decrease due to its resiliency. This accomplishes the locking of the tool.
'The centering accuracy in such tool holder depends on the geometric precision of every element of the tool holder assembly and the tool itself. The top picture in Fig. 2 shows just a theoretical case, where it is impossible to provide full conformity of external base conical surface of the collet (EX), with internal base conical surface of the tool holder's body (BIN), simultaneously with conformity of internal cylindrical base surface of the collet (IN), with cylindrical base surface of the tool (T).
Any kind of precision has a tolerance. As a result, when the tool is locked, it is locked only on one side of the collet. However, on the other side of the tool, micro clearances remain.
Therefore, the Tool Axis (TA) of the locked tool ends up in some indeterminate position inside the micro tapered angle (G).
The same happens in the plane perpendicular to the tool axis. The size (H), of all petals of a collet, slightly differs from one another due to machining tolerances. As a result, the appearance of micro clearance (C1) or (C2) occurs.
Theoretically, any solid body has 6 possible movements: translation along three axes X, Y, Z and rotation around the same three axes. To eliminate all 6 possible movements, 4 contact points and clamping forces are needed. This condition provides a determinate position for any solid body.
This theoretical statement is true in practice for a traditional collet. The contact between the tool, the petals of the collet and the tool holder, is possible by three petals on one side and only one petal on the other side. These 4 points (a-spot) are theoretically possible for traditional tool holder assembly, Fig. 2.
As we can see, even in static state, the tool is clamped just on one of the sides of the collet along its axis, and only three petals are in contact with the tool. This causes the tool to lock in some indeterminate position inside the micro tapered angle (G), thus the tool cannot coincide with the base surface of the tool holder body and spindle of a machine tool. The presence of micro clearances and imprecise positioning of the tool inside the micro tapered angle (G) is especially noticeable at high RPMs. In places where micro clearances exist, the collet expands due to the centrifugal forces, causing the tool to distort and thus creating even greater inaccuracy and vibrations.
Due to the fact that a traditional collet has only 4 contact points, the contact surface area with a tool is very small. Sometimes because of that, the tool slips inside the tool holder at higher torque caused by cutting forces. A slipped bit completely loses its setting position inside the tool holder.
The presented invention, Multi Ball Self adjusting Self-centering Tool Holder (MBSSTH), completely solves all of these problems.
All described above is rightly for positioning the Tool Holder itself inside the nest of a spindle of machine tool. The Multi Ball Self adjusting Self centering Clamping System (MBSSCS) can be used for positioning the Tool Holder itself inside the Spindle of machine tool. MBSSCS can be used even to directly position the Tool inside the Spindle of Machine Tool. In that case, some of the inaccuracies of the tool setting assemblies can be completely eliminated.
SUMMARY OF THE INVENTION
The most essential goal of current invention is to improve universal tool holding system:
~ Significantly increase accuracy of the tool holder especially at high RPM.
~ Significantly increase rigidity of tool holders.
~ Create a Universal Tool Holding system for different applications.
~ Reduce accuracy requirements of tool's base surface. Accuracy requirement is run-out only.
~ Increase the ability of the tool holder to work with wider range of tool diameters.
~ Improve tool-setting procedures.
~ Significantly increase accuracy of positioning the tool holder inside spindle of machine tool.
~ Creating a system where the tool is seated directly into the spindle of machine tool, and eliminating the whole bunch of inaccuracies inside the tool setting assemblies.
LIST OF FIGURES, WHICH ARE FORMING A PART OF THIS SPECIFICATION.
Fig. 1 is the photo of more traditional tool holder assembly that utilizes an external collet system (US Patent No 5,201,620).
Fig. 2 is an explanation of reasons of imperfection of a traditional tool holder assembly (US Patent No 5,201,620).
Fig. 3 is an explanation of main principal of the invention.
Fig. 4 is a primary design of the Multi Ball Self adjusting Self centering Insert (MBSSI) with two layers of balls.
Fig. 5 is a three-layer MBSSI where three different kinds of balls exist:
supporting balls (C), intermediate balls (E) and clamping Balls (D).
Fig. 6 is the MBSSI where the balls in each layer are equal in size but different from size of balls on another layer. This design allows using a conical surface of the body as a base surface.
Fig. 7 is a primary design of the Multi Ball Self adjusting Self centering Tool Holder (MBSSTH).
Fig. 8 is a design of the Multi Ball Self adjusting Self centering Insert (MBSSI) that is used to position MBSSTH inside Spindle of Machine Tool.
DETAILED DESCRIPTION OF THE INVENTION.
NATURE OF THE INVENTION
~ The main principle of the invention is based on a principal of a ball's self adjustment inside a closed space.
~ Another principal of the invention is a distribution of base point (a-spot) uniformly on a tool surface.
~ Using the principals increases accuracy because of the use of mufti base elements.
~ Statically determinate system with full force closure.
~ Using the principal of independently centering in line of tool's axis in every layer of balls.
. . . . . __ ", ~ . .. ..., s .. ~G m ~~.a.~._ . _._4 ~1~~.~;~. ~~~, .~ .., .v , . ,"~~~~w. , .,~.., ~_. _......
~:.~ ~.Y ..._ '~ - I S
Theoretical background of the idea of the Multi Ball Self adjusting Self centering Tool Holder (MBSSTH) is presented in Fig. 3.
Supporting balls (SB), have to have equal size. Clamping balls (CB), have to have equal size too.
Supporting and clamping balls can have equal or different sizes. Additional requirements include:
the base surface (B) has to be perpendicular to the main base cylindrical surface (M), and all clamping balls (CB), have to lie in one geometrical plane that is parallel to base surface (B). This goal is achieved by using bushing (F). Base cylindrical surface of the bushing (F) can slide along base cylindrical surface (MO of the body. The end surface of the bushing (F) is perpendicular to the base cylindrical surface of the bushing. In this case, all clamping balls (CB) will be in one geometrical plane that is parallel to base surface (B). Every 'ball here has 4 base a-spots. Every supporting ball (SB) has one a-spot with base surface (B), one a-spot with base surface (M), and two a-spots with two clamping balls (CB). Every clamping ball (CB) has two a-spots with supporting balls (SB), one a-spot with clamping bushing (F), and one a-spot with cylindrical surface of the tool (T). Due to self adjustment of the balls, all elements of a holder, even theoretically, are completely locked with full force closure and are in a position of stable equilibrium.
The tool is clamped by multiple a-spots, which provides high accuracy and high rigidity. Many layers of supporting and clamping balls are used to hold the tool. Since every layer of balls independently centers in line of tool's axis, the tool holder can hold tools with small conical or wavy surfaces. Only a run-out is important to provide high accuracy.
To provide simple tool setup procedure and simplifying tool change operations, all balls are assembled in one Multi Ball Self adjusting Self centering Insert (MBSSI). 'The MBSSI consist of high precision balls assembled in a special order and kept together like one flexible piece by flexible stuff or a special separator.
Fig. 4, Fig. S, Fig. 6 and Fig. 7 show a possible design of MBSSI.
Fig. 4 is a primary design of MBSSI with two layers of balls.
Fig. 5 is a three-layer MBSSI where three different kinds of balls exist:
supporting balls (SB), intermediate balls (IB) and clamping Balls (CB).
Fig. 6 is the MBSSI where the balls in each layer are equal in size but different from size of balls on another layer. This design allows the use of conical surface of the body like a base surface.
Fig. 7 is a primary design of the Multi Ball Self adjusting Self centering Tool Holder (MB S STH).
Fig. 1 is the photo of more traditional tool holder assembly that utilizes an external collet system (US Patent No 5,201,620).
Fig. 2 is an explanation of reasons of imperfection of a traditional tool holder assembly (US Patent No 5,201,620).
Fig. 3 is an explanation of main principal of the invention.
Fig. 4 is a primary design of the Multi Ball Self adjusting Self centering Insert (MBSSI) with two layers of balls.
Fig. 5 is a three-layer MBSSI where three different kinds of balls exist:
supporting balls (C), intermediate balls (E) and clamping Balls (D).
Fig. 6 is the MBSSI where the balls in each layer are equal in size but different from size of balls on another layer. This design allows using a conical surface of the body as a base surface.
Fig. 7 is a primary design of the Multi Ball Self adjusting Self centering Tool Holder (MBSSTH).
Fig. 8 is a design of the Multi Ball Self adjusting Self centering Insert (MBSSI) that is used to position MBSSTH inside Spindle of Machine Tool.
DETAILED DESCRIPTION OF THE INVENTION.
NATURE OF THE INVENTION
~ The main principle of the invention is based on a principal of a ball's self adjustment inside a closed space.
~ Another principal of the invention is a distribution of base point (a-spot) uniformly on a tool surface.
~ Using the principals increases accuracy because of the use of mufti base elements.
~ Statically determinate system with full force closure.
~ Using the principal of independently centering in line of tool's axis in every layer of balls.
. . . . . __ ", ~ . .. ..., s .. ~G m ~~.a.~._ . _._4 ~1~~.~;~. ~~~, .~ .., .v , . ,"~~~~w. , .,~.., ~_. _......
~:.~ ~.Y ..._ '~ - I S
Theoretical background of the idea of the Multi Ball Self adjusting Self centering Tool Holder (MBSSTH) is presented in Fig. 3.
Supporting balls (SB), have to have equal size. Clamping balls (CB), have to have equal size too.
Supporting and clamping balls can have equal or different sizes. Additional requirements include:
the base surface (B) has to be perpendicular to the main base cylindrical surface (M), and all clamping balls (CB), have to lie in one geometrical plane that is parallel to base surface (B). This goal is achieved by using bushing (F). Base cylindrical surface of the bushing (F) can slide along base cylindrical surface (MO of the body. The end surface of the bushing (F) is perpendicular to the base cylindrical surface of the bushing. In this case, all clamping balls (CB) will be in one geometrical plane that is parallel to base surface (B). Every 'ball here has 4 base a-spots. Every supporting ball (SB) has one a-spot with base surface (B), one a-spot with base surface (M), and two a-spots with two clamping balls (CB). Every clamping ball (CB) has two a-spots with supporting balls (SB), one a-spot with clamping bushing (F), and one a-spot with cylindrical surface of the tool (T). Due to self adjustment of the balls, all elements of a holder, even theoretically, are completely locked with full force closure and are in a position of stable equilibrium.
The tool is clamped by multiple a-spots, which provides high accuracy and high rigidity. Many layers of supporting and clamping balls are used to hold the tool. Since every layer of balls independently centers in line of tool's axis, the tool holder can hold tools with small conical or wavy surfaces. Only a run-out is important to provide high accuracy.
To provide simple tool setup procedure and simplifying tool change operations, all balls are assembled in one Multi Ball Self adjusting Self centering Insert (MBSSI). 'The MBSSI consist of high precision balls assembled in a special order and kept together like one flexible piece by flexible stuff or a special separator.
Fig. 4, Fig. S, Fig. 6 and Fig. 7 show a possible design of MBSSI.
Fig. 4 is a primary design of MBSSI with two layers of balls.
Fig. 5 is a three-layer MBSSI where three different kinds of balls exist:
supporting balls (SB), intermediate balls (IB) and clamping Balls (CB).
Fig. 6 is the MBSSI where the balls in each layer are equal in size but different from size of balls on another layer. This design allows the use of conical surface of the body like a base surface.
Fig. 7 is a primary design of the Multi Ball Self adjusting Self centering Tool Holder (MB S STH).
g -15 MBSSI can be designed in many different ways. ~"he main rule of design is very simple. All balls inside system have to have four a-spots, and have to be located in position of stable equilibrium.
The primary design of MBSSTH is shown in Fig. 7. This tool holder includes a body (O1), supporting balls (02), clamping balls (03), clamping nut (04), and elastic substance (05). The washers (06) and (07), are on opposite sides of the insert assembly.
Supporting balls (02), clamping balls (03), washers (06) and (07) are kept together by an elastic substance (05) as one flexible piece -Multi Ball Self adjusting Self centering Insert (MBSSI).
While tightening nut (04), up against body (0l), the distance (L) between butt-end of the nut (04), and base surface (B) of the body (01), decreases. That causes the space between supporting balls (02) to decrease, and clamping balls (03) to shift to the center and clamp circular surface of tool (06). Since all levels of balls work independently, centering is realized in every level in-line with the spindle's axis. That provides mufti-point contact with full force closure. The screw (08) is necessary for the tool's length setup.
The elastic substance (OS), which does not influence the accuracy of the tool holder, keeps all the balls together and returns the balls to their original position when the tool is released from the tool holder. In addition, it allows to keep all the balls together like one insert (MBSSI), so it allows changing MBSSI for different diameters of tools. Furthermore, the elastic substance (05) creates a great amount of additional torque between the body of the tool holder and the tool's surface. That helps to prevent the tool from slipping inside the tool holder.
Since the flexibility of the MBSSI is much higher than any kind of external spring collet of a traditional tool holder, the new design allows holding a very wide range of tool diameters with a single MBSSI.
Fig. 8 is a design of the Mufti Ball Self adjusting Self centering Insert (MBSSI) that is used for positioning MBSSTH inside Spindle of Machine Tool. Position O1 is a MBSSI for holding a tool inside tool holder. Position 02 is the body of a tool holder. Position 03 is a MBSSI for holding tool holder inside spindle O5. Position 04 is a pusher of spindle mechanism.
Activation of this pusher causes the decreasing of distance between butt end of the pusher and tool holder and shifting the s clamping balls to the center. Due to this, the tool holder will be centered and clamped inside the spindle with high precision and rigidity.
ACHIEVEMENTS
1. Since the new Multi Ball Self adjusting Self centering Insert has all elements in position of stable equilibrium and the system is statically determinate with full force closure, it is very stable.
2. The Multi Ball Self adjusting Self centering Insert provides distribution of base points uniformly on a tool's surface (a-spot) with full force closure, because of that, the MBSSTH
achieves a very high rigidity.
3. The MBSS Insert can hold tools with small conical or wavy surfaces, because every layer of balls independently centers in-line of the spindle's axis.
4. Because of multi point contact (a-spot) with full force closure, centrifugal forces cannot change position of balls or other elements of clamp. As a result, a high accuracy of radial positioning of a tool, even at high speed machining operations, is achieved.
5. Because MBSS Insert has mufti point contacts (a-spot) between all elements, its accuracy increases and makes the rigidity of the Tool Holder very high.
6. MBSSTH does not have any complicated details.
7. The MBSSI can be used for positioning the tool holder itself inside the spindle of machine tool.
The primary design of MBSSTH is shown in Fig. 7. This tool holder includes a body (O1), supporting balls (02), clamping balls (03), clamping nut (04), and elastic substance (05). The washers (06) and (07), are on opposite sides of the insert assembly.
Supporting balls (02), clamping balls (03), washers (06) and (07) are kept together by an elastic substance (05) as one flexible piece -Multi Ball Self adjusting Self centering Insert (MBSSI).
While tightening nut (04), up against body (0l), the distance (L) between butt-end of the nut (04), and base surface (B) of the body (01), decreases. That causes the space between supporting balls (02) to decrease, and clamping balls (03) to shift to the center and clamp circular surface of tool (06). Since all levels of balls work independently, centering is realized in every level in-line with the spindle's axis. That provides mufti-point contact with full force closure. The screw (08) is necessary for the tool's length setup.
The elastic substance (OS), which does not influence the accuracy of the tool holder, keeps all the balls together and returns the balls to their original position when the tool is released from the tool holder. In addition, it allows to keep all the balls together like one insert (MBSSI), so it allows changing MBSSI for different diameters of tools. Furthermore, the elastic substance (05) creates a great amount of additional torque between the body of the tool holder and the tool's surface. That helps to prevent the tool from slipping inside the tool holder.
Since the flexibility of the MBSSI is much higher than any kind of external spring collet of a traditional tool holder, the new design allows holding a very wide range of tool diameters with a single MBSSI.
Fig. 8 is a design of the Mufti Ball Self adjusting Self centering Insert (MBSSI) that is used for positioning MBSSTH inside Spindle of Machine Tool. Position O1 is a MBSSI for holding a tool inside tool holder. Position 02 is the body of a tool holder. Position 03 is a MBSSI for holding tool holder inside spindle O5. Position 04 is a pusher of spindle mechanism.
Activation of this pusher causes the decreasing of distance between butt end of the pusher and tool holder and shifting the s clamping balls to the center. Due to this, the tool holder will be centered and clamped inside the spindle with high precision and rigidity.
ACHIEVEMENTS
1. Since the new Multi Ball Self adjusting Self centering Insert has all elements in position of stable equilibrium and the system is statically determinate with full force closure, it is very stable.
2. The Multi Ball Self adjusting Self centering Insert provides distribution of base points uniformly on a tool's surface (a-spot) with full force closure, because of that, the MBSSTH
achieves a very high rigidity.
3. The MBSS Insert can hold tools with small conical or wavy surfaces, because every layer of balls independently centers in-line of the spindle's axis.
4. Because of multi point contact (a-spot) with full force closure, centrifugal forces cannot change position of balls or other elements of clamp. As a result, a high accuracy of radial positioning of a tool, even at high speed machining operations, is achieved.
5. Because MBSS Insert has mufti point contacts (a-spot) between all elements, its accuracy increases and makes the rigidity of the Tool Holder very high.
6. MBSSTH does not have any complicated details.
7. The MBSSI can be used for positioning the tool holder itself inside the spindle of machine tool.
8. The MBSSI can be used for direct positioning of the tool inside the spindle of machine tool and eliminate the whole bunch of inaccuracies inside the tool setting assemblies.
Claims (12)
1. High precision Tool holder where basing, centering and holding tools is realized by using special multi ball self-adjusting self-centering insert.
2. High precision Clamping system where basing, centering and holding tools is realized by using special mufti ball self-adjusting self-centering insert.
3. The Multi Ball Self-adjusting Self-centering Insert, where high precision balls are assembled in a specific order and are held together as one flexible piece by an elastic substance or a special separator.
4. The Multi Ball Self-adjusting Self-centering Insert, where balls are arranged in position of stable equilibrium and have permanent contact with each other, because of that the system is statically determinate and has a very high precision.
5. The Multi Ball Self-adjusting Self-centering Insert, which provides distribution of base point uniformly on a tool's surface (a-spot) with full force closure. Due to that, the Mufti Ball Self-adjusting Self-centering Tool Holder or Clamping System achieves a very high rigidity.
6. The Multi Ball Self-adjusting Self-centering Insert can hold tools with small conical or wavy surfaces, because every layer of balls independently centers along the spindle's axis.
7. The principal of a balls' self-adjustment inside a closed space.
8. The principal of uniform distribution of multiple base-points (a-spot) on the clamped surface of the tool.
9. The principal of statically determinate system with full force closure.
10. The elastic substance keeps all the balls together as one piece and creates additional torque between the body of the tool holder and the held tool. That helps to prevent the tool from slipping inside the tool holder.
11. Using the MBSSI for positioning the fool holder itself inside spindle of machine tool.
12. Using the MBSSI for direct positioning of tools inside spindle of machine tool and eliminate the whole bunch of inaccuracies inside the tool setting assemblies.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2488743 CA2488743A1 (en) | 2004-12-08 | 2004-12-08 | Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) |
| PCT/IB2005/054109 WO2006061789A2 (en) | 2004-12-08 | 2005-12-07 | Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2488743 CA2488743A1 (en) | 2004-12-08 | 2004-12-08 | Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2488743A1 true CA2488743A1 (en) | 2006-06-08 |
Family
ID=36577216
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2488743 Abandoned CA2488743A1 (en) | 2004-12-08 | 2004-12-08 | Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA2488743A1 (en) |
| WO (1) | WO2006061789A2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112720565A (en) * | 2020-12-21 | 2021-04-30 | 哈尔滨工业大学 | Pneumatic-based continuous variable-rigidity ball joint |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2405772A (en) * | 1944-07-31 | 1946-08-13 | Kingsbury Machine Tool Corp | Chuck assembly |
| US3684302A (en) * | 1970-08-05 | 1972-08-15 | Martin A Herman | Centering and holding fixture |
| SE427732B (en) * | 1979-09-20 | 1983-05-02 | Sandvik Ab | tool holder |
| US5013194A (en) * | 1988-09-08 | 1991-05-07 | Wienhold James L | Chuck assembly for tool bits |
| WO1998028100A1 (en) * | 1996-12-24 | 1998-07-02 | Tetsuro Tagami | Chuck device for cutting tool and assembly thereof |
| US6270085B1 (en) * | 1999-10-01 | 2001-08-07 | Tsai-Ching Chen | Chuck device for tool bits |
-
2004
- 2004-12-08 CA CA 2488743 patent/CA2488743A1/en not_active Abandoned
-
2005
- 2005-12-07 WO PCT/IB2005/054109 patent/WO2006061789A2/en not_active Application Discontinuation
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112720565A (en) * | 2020-12-21 | 2021-04-30 | 哈尔滨工业大学 | Pneumatic-based continuous variable-rigidity ball joint |
| CN112720565B (en) * | 2020-12-21 | 2022-03-11 | 哈尔滨工业大学 | Pneumatic-based continuous variable-rigidity ball joint |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2006061789A2 (en) | 2006-06-15 |
| WO2006061789A3 (en) | 2007-07-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4714389A (en) | Tool holder | |
| RU2342241C2 (en) | Clamp assembly | |
| US8286972B2 (en) | Low-vibration tool holder | |
| US7857557B2 (en) | Combination tool and method for metal-cutting machining of a drill-hole and its hole surface as well as cutting insert for such a combination tool | |
| US7357608B2 (en) | Rotary tapered tool holder | |
| JP2512454Y2 (en) | Rotary tool | |
| JP2000052176A (en) | Tool holder | |
| JPH05261609A (en) | Collet chuck | |
| WO2007070214A2 (en) | Rotary tapered tool holder with adapter sleeve | |
| SE450935B (en) | DEVICE FOR TRANSFER OF FLUID TO A ROTATING TOOL HOLDER | |
| CN100406192C (en) | Cutting tool | |
| US4828436A (en) | Cutting tool cartridge arrangement | |
| JP2007501718A (en) | Tool coupling | |
| US5813300A (en) | Precision center with an interchangeable double-arcuate floating collet | |
| US7690874B2 (en) | Rotary tapered tool holder with adapter sleeve | |
| CA2488743A1 (en) | Multi ball self-adjusting self-centering tool holder (mbssth) and multi ball self-adjusting self-centering clamping system (mbsscs) | |
| WO2023223308A1 (en) | Tool holder having a cylindrical fixation bore extending rearwardly from a front fixation surface and a fastening bore intersecting the front fixation surface | |
| EP0096669B1 (en) | Milling cutter | |
| EP0119750A2 (en) | Collet chucks | |
| US5551710A (en) | Universal modular sleeve-clamp systems | |
| US2678218A (en) | Universal expansion chuck | |
| JPH05177495A (en) | Tool holder | |
| JPH04244303A (en) | Fine adjustment cartridge mechanism and manufacture thereof for boring machine | |
| US5183272A (en) | Universal chuck stop | |
| US3740063A (en) | Floating tool holder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |