CA2057104A1 - Socket driver tool - Google Patents
Socket driver toolInfo
- Publication number
- CA2057104A1 CA2057104A1 CA 2057104 CA2057104A CA2057104A1 CA 2057104 A1 CA2057104 A1 CA 2057104A1 CA 2057104 CA2057104 CA 2057104 CA 2057104 A CA2057104 A CA 2057104A CA 2057104 A1 CA2057104 A1 CA 2057104A1
- Authority
- CA
- Canada
- Prior art keywords
- socket
- recess
- head
- insert
- end wall
- 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
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- Details Of Spanners, Wrenches, And Screw Drivers And Accessories (AREA)
Abstract
SOCKET DRIVER TOOL
Abstract of the Invention A socket driver tool useful for the removal of cap screws which prevents stripping and deformation of the cap screw head during the removal operation is disclosed.
The tool comprises a hexagonal key for insertion into the mating recess of the screw. A hollow cylindrical socket in coaxial relationship with said hexagonal key encapsulates the head of the screw, thereby preventing misalignment of the socket with the cap screw head. The tool may comprise one, two or three parts.
Abstract of the Invention A socket driver tool useful for the removal of cap screws which prevents stripping and deformation of the cap screw head during the removal operation is disclosed.
The tool comprises a hexagonal key for insertion into the mating recess of the screw. A hollow cylindrical socket in coaxial relationship with said hexagonal key encapsulates the head of the screw, thereby preventing misalignment of the socket with the cap screw head. The tool may comprise one, two or three parts.
Description
2~71~
SOCKET DRIVER TOOL
Field of the Invention The present inventlon relates to a socket for cap screws and more specifically a socket which prevents stripping and deformation of the heads of cap screws in situations where the threaded portion of the bolt is seized in the work from which the removal is desired.
Background of the Invention Cap screws are commonly used structural fasteners characterized by head portions having central hexagonally shaped recesses therein. Cap screws are removed by use of a commonly known hexagonal key socket also called an allen key which is inserted into the hexagonal recess in the head of the cap screw and twisted in the proper direction to remove the screw from the structure.
Because of contamination and exposure to heat, sometimes the cap screw will become seized in its place in the bore of a workpiece. The use of hexagonal key sockets for the removal of seized cap screws requires a great deal of care to maintain a square alignment of the key to the hexagonal recess in the screw head. When torque is applied to the key, any misalignment may result in the undesirable stripping of the recess in the cap screw head (i.e. the rounding out of the "flats" of the hexagonal recess) or further, the deformation of the wall around the recess. Stripping and head deformation is 20~71~4 common with cap screws whose heads have been modified to be fitted with lock wires.
When the recess in the cap screw is stripped the screw may only be removed by complex and tedious, time consuming methods. To aid in the removal of seized cap screws hexagonal key sockets have been used in combination with the application of wrench-type jaws on the outer portions of the head. However, this arrangement is extremely bulky and the high pressure, point-contact of the jaws often crushes the head of the screw.
The problems associated with the removal of cap screws in dangerous environments, such as areas having high radioactivity levels are only amplified by the hostile environment. In nuclear reactors, the removal of feeder pipes from fuel channel end fittings requires that a flange be disconnected from the end fitting by the removal of four cap screws. This must be completed as quickly as possible to reduce the worker's exposure to radiation. The cap screws are often seized into the end fitting feeder port flange and the stripping and deformation of cap screw heads using the hexagonal key socket is common. When the heads of the cap screws are damaged the worker must spend an extended amount of time exposed to the radioactivity.
An improved cap screw removal socket is taught by German Democratic Republic Patent 144,731, issued November 5, 1980 to Gerlach et al. In this socket the hexagonal key is surrounded by a saw toothed flange for engaging the top surface of the cap screw. The flange provides beneficial frictional engagement to aid in the removal of the cap screw, while preventing the problem of point contact. However, misalignment of the hexagonal key with the recess in the cap screw head can still take place leading to stripping of the head. Further the socket of the German patent gives no support to the wall around the recess and does not prevent wall deformation.
~0~710~
SOCKET DRIVER TOOL
Field of the Invention The present inventlon relates to a socket for cap screws and more specifically a socket which prevents stripping and deformation of the heads of cap screws in situations where the threaded portion of the bolt is seized in the work from which the removal is desired.
Background of the Invention Cap screws are commonly used structural fasteners characterized by head portions having central hexagonally shaped recesses therein. Cap screws are removed by use of a commonly known hexagonal key socket also called an allen key which is inserted into the hexagonal recess in the head of the cap screw and twisted in the proper direction to remove the screw from the structure.
Because of contamination and exposure to heat, sometimes the cap screw will become seized in its place in the bore of a workpiece. The use of hexagonal key sockets for the removal of seized cap screws requires a great deal of care to maintain a square alignment of the key to the hexagonal recess in the screw head. When torque is applied to the key, any misalignment may result in the undesirable stripping of the recess in the cap screw head (i.e. the rounding out of the "flats" of the hexagonal recess) or further, the deformation of the wall around the recess. Stripping and head deformation is 20~71~4 common with cap screws whose heads have been modified to be fitted with lock wires.
When the recess in the cap screw is stripped the screw may only be removed by complex and tedious, time consuming methods. To aid in the removal of seized cap screws hexagonal key sockets have been used in combination with the application of wrench-type jaws on the outer portions of the head. However, this arrangement is extremely bulky and the high pressure, point-contact of the jaws often crushes the head of the screw.
The problems associated with the removal of cap screws in dangerous environments, such as areas having high radioactivity levels are only amplified by the hostile environment. In nuclear reactors, the removal of feeder pipes from fuel channel end fittings requires that a flange be disconnected from the end fitting by the removal of four cap screws. This must be completed as quickly as possible to reduce the worker's exposure to radiation. The cap screws are often seized into the end fitting feeder port flange and the stripping and deformation of cap screw heads using the hexagonal key socket is common. When the heads of the cap screws are damaged the worker must spend an extended amount of time exposed to the radioactivity.
An improved cap screw removal socket is taught by German Democratic Republic Patent 144,731, issued November 5, 1980 to Gerlach et al. In this socket the hexagonal key is surrounded by a saw toothed flange for engaging the top surface of the cap screw. The flange provides beneficial frictional engagement to aid in the removal of the cap screw, while preventing the problem of point contact. However, misalignment of the hexagonal key with the recess in the cap screw head can still take place leading to stripping of the head. Further the socket of the German patent gives no support to the wall around the recess and does not prevent wall deformation.
~0~710~
Driver tools have been taught which encapsulate the head of the screw on which they act. For example United States Patents 4,800,788, issued January 31, 1989 to Goldstein and 4,285,255, issued August 25, 1981 to Winfrey, are useful especially in locating the screw head and preventing lateral slipping of the driver tool, but do not appear to teach much more than that.
The cap screw removal socket which has been developed and is described herein, fully encapsulates the head of the cap screw, preventing the subsequent misalignment of the hexagonal key portion of the socket with the recess in the head of the screw while adding beneficial frictional energy to the head, thereby providing a socket which can be used at high torques to remove cap screws efficiently, including those cap screws which are highly seized in the workpiece.
Object of the Invention An object of the present invention is to provide a socket driver tool for cap screws which prevents stripping and deformation of the screw head during removal.
It is another object of the present invention to provide a socket driver tool with a replaceable hexagonal key insert for removing cap screws without stripping and deformation.
It is a further object of the present invention to provide a socket driver tool with enhanced engagement of the cap screw during removal to prevent stripping and substantial deformation.
Summary of the Invention According to the invention there is provided a socket driver tool for cap screws. The socket has a 20~710~
hexagonal key portion and a cylindrical socket which act together to remove cap screws.
According to a broad aspect of the invention there is provided a socket driver tool for cap screws. A cap screw is characterized as having a head with a central hexagonally shaped recess. The socket driver tool comprises a hollow cylindrical socket which has an end wall to which torque may be applied, such as would be with a torque socket wrench, and an open end opposite the end wall. The cylindrical socket is adapted to snugly fit over and encapsulate the head of the cap screw and the inner surfaces of the cylindrical socket are able to contact the head of the screw. In addition, the socket driver tool comprises a hexagonal key portion, corresponding to the hexagonal recess in the screw, which is concentric with and extends from the end wall within and in coaxial relationship with the cylindrical socket so that it fits within and cooperates with the central hexagonal recess in the screw head when the cylindrical socket is placed over the head of the screw.
In accordance with another embodiment of the invention there is provided a socket driver tool for cap screws similar to that above except that the socket will receive and drive a replaceable hexagonal key insert.
In accordance with a further embodiment of the invention there is provided a socket driver tool for cap screws similar to that above except that the socket will provide additional engagement to the head of the screw by scoring the outer surfaces thereof.
Brief Description of the Drawings For a better understanding of the nature and objects of the present invention reference may be had by way of example to the accompanying diagrammatic drawings, in which:
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Figure 1, is a view of a cap screw with a hexagonal key aligned with the hexagonal recess thereof;
Figure 2, is a view of the socket driver tool of the present invention;
Figure 3, is a cutaway view of the socket of Figure 2 showing the placement of the cap screw within the socket;
Figure 4, is a view of an alternate embodiment of the present invention, including a cylindrical socket and a replaceable hexagonal key insert; and Figure 5, is a view of an modification of the socket of Figure 4 wherein the hexagonal key is separated from the base of the insert;
Figure 6, is a view of an alternate embodiment of the present invention including a cylindrical socket with splines with cutting edges for scoring the surface of the cap screw head and a replaceable hexagonal key insert.
Des¢ription of the Preferred Embodiment In Figure 1, a cap screw 1, such as would be commonly used as a structural fastener characterized by a head 2 having a central hexagonally shaped recess 3 therein, is illustrated. Cap screws are normally removed by the action of a hexagonal key 18. To remove the cap screw 1, the hexagonal key 18 is inserted into the recess 3 of the screw 1 and twisted in the proper direction.
Referring to Figure 2, there is shown a socket driver tool 10 for cap screws. The socket driver tool 10 comprises a hollow cylindrical socket 12 which has an end wall 14 and an open end 13, opposite the end wall 14.
The open end 13 allows for the socket to be placed over the head of the screw. The end wall 14 is adapted for connection to a standard socket driver (not shown). The connection is of the kind commonly known in the art for 20~7~4 torque sources such as ratchet handles or pneumatic wrenches. Extending from the end wall 14 and concentric with the cylindrical socket 12 is a hexagonal key portion 18, corresponding to the hexagonal recess in the cap screw. In Figure 3 it can be seen that the hexagonal key portion 18 extends from the end wall 14 so as to fit into the recess 3 in the screw when the cylindrical socket 12 is placed over the head of the cap screw 2. When the socket is placed over the head of the cap screw 2 the cylindrical socket 12 fits snugly over and encapsulates the head 2.
As will be understood by those knowledgeable in the art, when sockets are rotated, there will often be a degree of misalignment of the socket to the head of the screw. Oftentimes,, when using traditional hexagonal key sockets misalignment of the key with the cap screw head leads to stripping of the head. However, referring again to Figure 3, the socket of the present invention fits snugly over the head of the screw 2 so that misalignment is next to impossible. However, when there is any misalignment the inner portions 16 of the cylindrical socket 12 make contact with the head 2. When torque is applied, this contact translates into frictional engagement of the socket which acts positively to remove the screw. The contact which occurs is not point-contact, rather substantial surface contact.
Removal of the screw becomes a combination of the action of the hexagonal key 18 on the recess 3 in the head 2 and the action of the cylindrical socket 12 on the head 2 of the screw.
The problems associated with misalignment also often lead to a deformation of the wall 4 surrounding the recess 3. In some cases, the wall 4 will break away from the head 2. This problem is prevented using the socket of the present invention. The cylindrical socket 12 of the socket acts to support the walls 4 of the head 20~10~
surrounding the recess 3 when the hexagonal key 18 is acting inside the recess 3. In fact any elastic deformation of the cap screw head occurring during the application of torque acts to briny the head and cylindrical socket into greater frictional engagement.
This also acts in the removal of the screw.
This socket has been found to remove cap screws very efficiently, including those screws which are seized in the work. Where the weak part of the screw, using traditional removal means, would be the head, the weakest part of the screw, using the socket of the present invention, has been found to be the threaded portion of the screw just below the head.
Referring back to Figure 2, to enhance the frictional action of the socket 12 during removal of cap screws, the inner surfaces 16 of the cylindrical socket 12 can be modified to have a rough finish. The rough finish will act to further engage the head of the screw, when the head of the screw makes contact with the inner surfaces 16 of the cylindrical socket 12. Preferably the rough finish is in the form of striations 17 running from the open end 13 to the end wall 14 that will immediately engage the head of the screw as it is inserted into the socket 10.
Referring to Figure 4, an alternate embodiment of the socket driver tool 19 for cap screws is shown. The socket driver tool comprises two separate parts: a hollow cylindrical socket 12 similar to that described herein before, additionally having a recess 22 of predetermined shape in the end wall 14 of the cylindrical socket to receive and drive a replaceable insert 25, which is inserted into the recess 22 of the cylindrical socket 12.
The insert 25 itself comprises a base 26, which snugly fits into the recess 22 and a hexagonal key portion 27 extending from the base 26, which corresponds to the hexagonal recess of the screw. The shape of the recess 20~71~
22 of the cylindrical socket 12 is selected to ensure that the insert 25 will not move or rotate within the recess 22 and therefor will remain in a single orientation when the insert is driven by the socket 19.
Preferably the recess 22 of the cylindrical socket will be selected to be a shape which will accept a hexagonal insert (as shown). This shape is known by those skilled in the art. The hexagonal key portion 27 extends from the base 26 in coaxial relationship with the socket to allow it to fit within and cooperate with the central hexagonally shaped recess in the head of the screw when the socket is assembled and used. That is when the insert is placed within the recess of the cylindrical socket and the cylindrical socket is placed over the head of the screw. This is substantially the same as the socket of Figure 3.
To enhance the use of the present socket 19 the insert 25 is held within the recess 22 by means of a pin 29 which is inserted through a bore 28 in a side wall 23 of the recess 22 into a indentation 30 in the base 26 of the insert 25. The bore 28 corresponds to the size of the pin 29 while the indentation 30 is a small cavity in the base 26 of the insert 25. The pin 29 is inserted when the bore 28 and indentation 30 are lined up. To remove the insert 25, the pin 29 is simply withdrawn from the bore 28.
Alternatively, the insert could be held within the recess by means of a D-dent pin on the base of the insert (not shown), which cooperates with a bore through a side wall of the recess. The bore is much the same as that bore 28 shown in Figure 4. The insert is placed into the recess by aligning the pin with the bore in the recess and forcing the insert into the recess. When the insert is in place, the pin extends into the bore holding the insert securely in the recess. The insert is removed by inserting a suitable object into the bore to force the 2~710~
_g_ pin into a retracted position, whil~e at the same time pulling the insert out of the recess. The action of a D-dent pin is known to those skilled in the art.
To enhance the frictional action provided by the cylindrical socket 12 of the socket of the present embodiment 19, the inner surfaces 16 of the cylindrical socket 12 can be modified to define a roughened finish, as shown in Figure 4. The roughened finish is as described herein before and is preferably in the form of striations (as shown) running from the open end 13 to the recess 22 that will engage the head of the screw as it is inserted into the socket.
It is known that, under continuous use, the hexagonal key sockets will wear down and replacement will be required. The hexagonal key portion of the present invention will also wear down over time and need replacing. The embodiment of the present invention having a separate hexagonal key insert allows the simple replacement of the insert rather than the replacement of the entire socket. This results in a reduction in replacement costs.
Cap screws are commonly available having a common sized central hexagonal recess but in a wide variety of external head diameters. The cylindrical socket of the driver tool of the present invention can be produced in a range of diameters corresponding to the external head diameters. These sockets could then be marketed as a set. To reduce the weight of the set, the two part sockets could be produced with a common shared hexagonal key insert. In this way a set of sockets could be produced which can be used on a variety of cap screws to control costs.
With reference to Figure 5, a modification of the insert of the socket of Figure 4 is shown where the hexagonal key 50 is separated from base 42. During use the replaceable hexagonal key 50 is securely held within 2~71~
the base 42. The base 42, as herein before described, fits snugly into and is driven by the recess 22 in the end wall 14 of the cylindrical socket 12 and remains in a single orientation therein. A central portion of the base 42 has been modified to define a recess 44 for accepting the replaceable hexagonal key 50. The replaceable hexagonal key portion 50 is comprised of a first end 52, adapted to conform to, be held within and be driven by the recess 44 in the base 42 and a second end 54, opposite the first end 52, which conforms to the central hexagonal recess in the head of the cap screw.
The recess 44 of the base 42 is preferably made to be square (as shown) and the end of the key 52 which fits within this recess 44 conforms to the square shape (as shown). When the key 50 is held within the recess 44 in the base 42, the opposite end 54 extends out from the base 42 in coaxial relationship with the cylindrical socket 12. In this way the hexagonal key portion 50 fits within and cooperates with the recess in the head of the screw when the socket is assembled and used. That is, when the hexagonal key is fitted into the base, the base is placed into the cylindrical socket and the socket is placed over the head of the screw. This is substantially the same as the socket arrangement of Figure 3.
The use of the base 42 and replaceable hexagonal key 50 can be enhanced by a similar pin arrangement as that described in regards to the two piece socket (Figure 4) with obvious modifications (not shown). The pin must pass through bores in both the recess 22 of the end wall of the socket and the base 42 into an indentation in the end 52 of the replaceable hexagonal key 50 that fits within the recess 44 of the base. The use of D-dent pins in this embodiment is also possible (shown in Figure 5).
In this case two D-dent pins offset to each other are required. One of the pin/bore arrangements 56, 58 acts between the base 42 and the recess 22 and the other 20~71~
pin/bore arrangement 60, 62 acts between the key 50 and the base 42.
The benefits of using the socket with the replaceable insert are only further enhanced by the socket with the two piece insert.
Referring to Figure 6, an alternate embodiment of the socket driver tool for cap screws is shown. The socket driver tool comprises three parts: a hollow cylindrical socket 12 having a recess 22 in the end wall similar to that described herein before in regards to the embodiment of Figure 4, additionally having splines 66 disposed about the inner surfaces 16 of the socket. The splines extend from the open end 13 of the socket to the recess 22 in coaxial relationship with the socket 12; a replaceable insert 25 in accordance with that insert 25 described in regards to Figure 4; and a spring means 74 acting between the end wall 14 of the socket 12 and the insert 25.
The socket of the present embodiment acts to provide enhanced engagement of the head of the cap screw during removal. This is accomplished by the action of the splines 66. The splines 66 are machined to define cutting edges 69 adjacent the open end 13 which will score the head of the screw when the socket is placed over the head to form grooves thereon (not shown). The splines 66 slide into the grooves formed on the head of the screw as the screw is forced into the socket 12. In this way the socket firmly engages the screw to help in the removal of the screw when torque is applied. To form the grooves the open end of the cylindrical socket is aligned with the head of the cap screw and forced over the head of the cap screw using a suitable instrument.
This will preferably be carried out by tapping the aligned socket with a hammer.
20S71 ~
The spring device 74 is located between the end wall 14 of the cylindrical socket 12 and the insert 25. The spring device 74 acts to hold the insert 25 toward the open end 13 of the cylindrical socket 12 when the socket is not in use. The spring 74 also allows the insert 25 to be pushed toward the end wall 14 of the socket 12 as the socket is placed over the head of the screw. The insert 25 must be held toward the open end 13 so that the hexagonal key portion 27 of the insert 25 can be aligned with the hexagonal recess of the screw before the socket 12 is forced over the head of the screw. The spring 74 ensures that the hexagonal key portion 27 of the insert 25 remains in the recess of the screw regardless of how far the screw is forced into the socket.
It will be appreciated that the recess 22 in the end wall 14 of the socket 12 which accepts the insert 25 will have to be extended up the inner surfaces 16 of the cylindrical socket 12 so that the insert 25 can move in a coaxial direction within the socket 12 and be driven by the socket 12 at any point along the inner surfaces 16.
Further, the splines 66 have to be oriented within the cylindrical socket 12 to correspond with the shape of the recess 22 so that the insert 25 can move freely in coaxial relationship with the socket 12 and the insert 25 can be removed from the socket 12.
To enhance the use of this socket the insert 25 is held within the socket 12. The insert may be held by means of a D-dent pin 76 on the base 26 of the insert 25, which cooperates with a slot 78 through a wall 23 of the recess 22. The slot 78 is of adequate length to allow the pin 76 to move up and down as the insert 25 moves coaxially in the socket 12. The insert 25 is placed into the recess 22 by aligning the pin 76 with the slot 78 and forcing the insert 25 into the recess 22 against the spring means 74. When the insert 25 is in place the pin 2~5710~
G~CAN 3064 76 extends into the slot 78 holding the insert 25 securely in the recess 22.
The socket of the present embodiment has been found to remove seized cap screws very efficiently. The action of the splines alone, without the use of the insert, can also used to remove cap screws.
The cap screw removal socket which has been developed and is described herein, fully encapsulates the head of the cap screw, preventing the subsequent misalignment of the hexagonal key portion of the socket with the recess in the head of the screw while adding beneficial frictional energy to the head, thereby providing a socket which can be used at high torques to remove cap screws efficiently, including those cap screws which are highly seized in the workpiece.
Object of the Invention An object of the present invention is to provide a socket driver tool for cap screws which prevents stripping and deformation of the screw head during removal.
It is another object of the present invention to provide a socket driver tool with a replaceable hexagonal key insert for removing cap screws without stripping and deformation.
It is a further object of the present invention to provide a socket driver tool with enhanced engagement of the cap screw during removal to prevent stripping and substantial deformation.
Summary of the Invention According to the invention there is provided a socket driver tool for cap screws. The socket has a 20~710~
hexagonal key portion and a cylindrical socket which act together to remove cap screws.
According to a broad aspect of the invention there is provided a socket driver tool for cap screws. A cap screw is characterized as having a head with a central hexagonally shaped recess. The socket driver tool comprises a hollow cylindrical socket which has an end wall to which torque may be applied, such as would be with a torque socket wrench, and an open end opposite the end wall. The cylindrical socket is adapted to snugly fit over and encapsulate the head of the cap screw and the inner surfaces of the cylindrical socket are able to contact the head of the screw. In addition, the socket driver tool comprises a hexagonal key portion, corresponding to the hexagonal recess in the screw, which is concentric with and extends from the end wall within and in coaxial relationship with the cylindrical socket so that it fits within and cooperates with the central hexagonal recess in the screw head when the cylindrical socket is placed over the head of the screw.
In accordance with another embodiment of the invention there is provided a socket driver tool for cap screws similar to that above except that the socket will receive and drive a replaceable hexagonal key insert.
In accordance with a further embodiment of the invention there is provided a socket driver tool for cap screws similar to that above except that the socket will provide additional engagement to the head of the screw by scoring the outer surfaces thereof.
Brief Description of the Drawings For a better understanding of the nature and objects of the present invention reference may be had by way of example to the accompanying diagrammatic drawings, in which:
20~710~
Figure 1, is a view of a cap screw with a hexagonal key aligned with the hexagonal recess thereof;
Figure 2, is a view of the socket driver tool of the present invention;
Figure 3, is a cutaway view of the socket of Figure 2 showing the placement of the cap screw within the socket;
Figure 4, is a view of an alternate embodiment of the present invention, including a cylindrical socket and a replaceable hexagonal key insert; and Figure 5, is a view of an modification of the socket of Figure 4 wherein the hexagonal key is separated from the base of the insert;
Figure 6, is a view of an alternate embodiment of the present invention including a cylindrical socket with splines with cutting edges for scoring the surface of the cap screw head and a replaceable hexagonal key insert.
Des¢ription of the Preferred Embodiment In Figure 1, a cap screw 1, such as would be commonly used as a structural fastener characterized by a head 2 having a central hexagonally shaped recess 3 therein, is illustrated. Cap screws are normally removed by the action of a hexagonal key 18. To remove the cap screw 1, the hexagonal key 18 is inserted into the recess 3 of the screw 1 and twisted in the proper direction.
Referring to Figure 2, there is shown a socket driver tool 10 for cap screws. The socket driver tool 10 comprises a hollow cylindrical socket 12 which has an end wall 14 and an open end 13, opposite the end wall 14.
The open end 13 allows for the socket to be placed over the head of the screw. The end wall 14 is adapted for connection to a standard socket driver (not shown). The connection is of the kind commonly known in the art for 20~7~4 torque sources such as ratchet handles or pneumatic wrenches. Extending from the end wall 14 and concentric with the cylindrical socket 12 is a hexagonal key portion 18, corresponding to the hexagonal recess in the cap screw. In Figure 3 it can be seen that the hexagonal key portion 18 extends from the end wall 14 so as to fit into the recess 3 in the screw when the cylindrical socket 12 is placed over the head of the cap screw 2. When the socket is placed over the head of the cap screw 2 the cylindrical socket 12 fits snugly over and encapsulates the head 2.
As will be understood by those knowledgeable in the art, when sockets are rotated, there will often be a degree of misalignment of the socket to the head of the screw. Oftentimes,, when using traditional hexagonal key sockets misalignment of the key with the cap screw head leads to stripping of the head. However, referring again to Figure 3, the socket of the present invention fits snugly over the head of the screw 2 so that misalignment is next to impossible. However, when there is any misalignment the inner portions 16 of the cylindrical socket 12 make contact with the head 2. When torque is applied, this contact translates into frictional engagement of the socket which acts positively to remove the screw. The contact which occurs is not point-contact, rather substantial surface contact.
Removal of the screw becomes a combination of the action of the hexagonal key 18 on the recess 3 in the head 2 and the action of the cylindrical socket 12 on the head 2 of the screw.
The problems associated with misalignment also often lead to a deformation of the wall 4 surrounding the recess 3. In some cases, the wall 4 will break away from the head 2. This problem is prevented using the socket of the present invention. The cylindrical socket 12 of the socket acts to support the walls 4 of the head 20~10~
surrounding the recess 3 when the hexagonal key 18 is acting inside the recess 3. In fact any elastic deformation of the cap screw head occurring during the application of torque acts to briny the head and cylindrical socket into greater frictional engagement.
This also acts in the removal of the screw.
This socket has been found to remove cap screws very efficiently, including those screws which are seized in the work. Where the weak part of the screw, using traditional removal means, would be the head, the weakest part of the screw, using the socket of the present invention, has been found to be the threaded portion of the screw just below the head.
Referring back to Figure 2, to enhance the frictional action of the socket 12 during removal of cap screws, the inner surfaces 16 of the cylindrical socket 12 can be modified to have a rough finish. The rough finish will act to further engage the head of the screw, when the head of the screw makes contact with the inner surfaces 16 of the cylindrical socket 12. Preferably the rough finish is in the form of striations 17 running from the open end 13 to the end wall 14 that will immediately engage the head of the screw as it is inserted into the socket 10.
Referring to Figure 4, an alternate embodiment of the socket driver tool 19 for cap screws is shown. The socket driver tool comprises two separate parts: a hollow cylindrical socket 12 similar to that described herein before, additionally having a recess 22 of predetermined shape in the end wall 14 of the cylindrical socket to receive and drive a replaceable insert 25, which is inserted into the recess 22 of the cylindrical socket 12.
The insert 25 itself comprises a base 26, which snugly fits into the recess 22 and a hexagonal key portion 27 extending from the base 26, which corresponds to the hexagonal recess of the screw. The shape of the recess 20~71~
22 of the cylindrical socket 12 is selected to ensure that the insert 25 will not move or rotate within the recess 22 and therefor will remain in a single orientation when the insert is driven by the socket 19.
Preferably the recess 22 of the cylindrical socket will be selected to be a shape which will accept a hexagonal insert (as shown). This shape is known by those skilled in the art. The hexagonal key portion 27 extends from the base 26 in coaxial relationship with the socket to allow it to fit within and cooperate with the central hexagonally shaped recess in the head of the screw when the socket is assembled and used. That is when the insert is placed within the recess of the cylindrical socket and the cylindrical socket is placed over the head of the screw. This is substantially the same as the socket of Figure 3.
To enhance the use of the present socket 19 the insert 25 is held within the recess 22 by means of a pin 29 which is inserted through a bore 28 in a side wall 23 of the recess 22 into a indentation 30 in the base 26 of the insert 25. The bore 28 corresponds to the size of the pin 29 while the indentation 30 is a small cavity in the base 26 of the insert 25. The pin 29 is inserted when the bore 28 and indentation 30 are lined up. To remove the insert 25, the pin 29 is simply withdrawn from the bore 28.
Alternatively, the insert could be held within the recess by means of a D-dent pin on the base of the insert (not shown), which cooperates with a bore through a side wall of the recess. The bore is much the same as that bore 28 shown in Figure 4. The insert is placed into the recess by aligning the pin with the bore in the recess and forcing the insert into the recess. When the insert is in place, the pin extends into the bore holding the insert securely in the recess. The insert is removed by inserting a suitable object into the bore to force the 2~710~
_g_ pin into a retracted position, whil~e at the same time pulling the insert out of the recess. The action of a D-dent pin is known to those skilled in the art.
To enhance the frictional action provided by the cylindrical socket 12 of the socket of the present embodiment 19, the inner surfaces 16 of the cylindrical socket 12 can be modified to define a roughened finish, as shown in Figure 4. The roughened finish is as described herein before and is preferably in the form of striations (as shown) running from the open end 13 to the recess 22 that will engage the head of the screw as it is inserted into the socket.
It is known that, under continuous use, the hexagonal key sockets will wear down and replacement will be required. The hexagonal key portion of the present invention will also wear down over time and need replacing. The embodiment of the present invention having a separate hexagonal key insert allows the simple replacement of the insert rather than the replacement of the entire socket. This results in a reduction in replacement costs.
Cap screws are commonly available having a common sized central hexagonal recess but in a wide variety of external head diameters. The cylindrical socket of the driver tool of the present invention can be produced in a range of diameters corresponding to the external head diameters. These sockets could then be marketed as a set. To reduce the weight of the set, the two part sockets could be produced with a common shared hexagonal key insert. In this way a set of sockets could be produced which can be used on a variety of cap screws to control costs.
With reference to Figure 5, a modification of the insert of the socket of Figure 4 is shown where the hexagonal key 50 is separated from base 42. During use the replaceable hexagonal key 50 is securely held within 2~71~
the base 42. The base 42, as herein before described, fits snugly into and is driven by the recess 22 in the end wall 14 of the cylindrical socket 12 and remains in a single orientation therein. A central portion of the base 42 has been modified to define a recess 44 for accepting the replaceable hexagonal key 50. The replaceable hexagonal key portion 50 is comprised of a first end 52, adapted to conform to, be held within and be driven by the recess 44 in the base 42 and a second end 54, opposite the first end 52, which conforms to the central hexagonal recess in the head of the cap screw.
The recess 44 of the base 42 is preferably made to be square (as shown) and the end of the key 52 which fits within this recess 44 conforms to the square shape (as shown). When the key 50 is held within the recess 44 in the base 42, the opposite end 54 extends out from the base 42 in coaxial relationship with the cylindrical socket 12. In this way the hexagonal key portion 50 fits within and cooperates with the recess in the head of the screw when the socket is assembled and used. That is, when the hexagonal key is fitted into the base, the base is placed into the cylindrical socket and the socket is placed over the head of the screw. This is substantially the same as the socket arrangement of Figure 3.
The use of the base 42 and replaceable hexagonal key 50 can be enhanced by a similar pin arrangement as that described in regards to the two piece socket (Figure 4) with obvious modifications (not shown). The pin must pass through bores in both the recess 22 of the end wall of the socket and the base 42 into an indentation in the end 52 of the replaceable hexagonal key 50 that fits within the recess 44 of the base. The use of D-dent pins in this embodiment is also possible (shown in Figure 5).
In this case two D-dent pins offset to each other are required. One of the pin/bore arrangements 56, 58 acts between the base 42 and the recess 22 and the other 20~71~
pin/bore arrangement 60, 62 acts between the key 50 and the base 42.
The benefits of using the socket with the replaceable insert are only further enhanced by the socket with the two piece insert.
Referring to Figure 6, an alternate embodiment of the socket driver tool for cap screws is shown. The socket driver tool comprises three parts: a hollow cylindrical socket 12 having a recess 22 in the end wall similar to that described herein before in regards to the embodiment of Figure 4, additionally having splines 66 disposed about the inner surfaces 16 of the socket. The splines extend from the open end 13 of the socket to the recess 22 in coaxial relationship with the socket 12; a replaceable insert 25 in accordance with that insert 25 described in regards to Figure 4; and a spring means 74 acting between the end wall 14 of the socket 12 and the insert 25.
The socket of the present embodiment acts to provide enhanced engagement of the head of the cap screw during removal. This is accomplished by the action of the splines 66. The splines 66 are machined to define cutting edges 69 adjacent the open end 13 which will score the head of the screw when the socket is placed over the head to form grooves thereon (not shown). The splines 66 slide into the grooves formed on the head of the screw as the screw is forced into the socket 12. In this way the socket firmly engages the screw to help in the removal of the screw when torque is applied. To form the grooves the open end of the cylindrical socket is aligned with the head of the cap screw and forced over the head of the cap screw using a suitable instrument.
This will preferably be carried out by tapping the aligned socket with a hammer.
20S71 ~
The spring device 74 is located between the end wall 14 of the cylindrical socket 12 and the insert 25. The spring device 74 acts to hold the insert 25 toward the open end 13 of the cylindrical socket 12 when the socket is not in use. The spring 74 also allows the insert 25 to be pushed toward the end wall 14 of the socket 12 as the socket is placed over the head of the screw. The insert 25 must be held toward the open end 13 so that the hexagonal key portion 27 of the insert 25 can be aligned with the hexagonal recess of the screw before the socket 12 is forced over the head of the screw. The spring 74 ensures that the hexagonal key portion 27 of the insert 25 remains in the recess of the screw regardless of how far the screw is forced into the socket.
It will be appreciated that the recess 22 in the end wall 14 of the socket 12 which accepts the insert 25 will have to be extended up the inner surfaces 16 of the cylindrical socket 12 so that the insert 25 can move in a coaxial direction within the socket 12 and be driven by the socket 12 at any point along the inner surfaces 16.
Further, the splines 66 have to be oriented within the cylindrical socket 12 to correspond with the shape of the recess 22 so that the insert 25 can move freely in coaxial relationship with the socket 12 and the insert 25 can be removed from the socket 12.
To enhance the use of this socket the insert 25 is held within the socket 12. The insert may be held by means of a D-dent pin 76 on the base 26 of the insert 25, which cooperates with a slot 78 through a wall 23 of the recess 22. The slot 78 is of adequate length to allow the pin 76 to move up and down as the insert 25 moves coaxially in the socket 12. The insert 25 is placed into the recess 22 by aligning the pin 76 with the slot 78 and forcing the insert 25 into the recess 22 against the spring means 74. When the insert 25 is in place the pin 2~5710~
G~CAN 3064 76 extends into the slot 78 holding the insert 25 securely in the recess 22.
The socket of the present embodiment has been found to remove seized cap screws very efficiently. The action of the splines alone, without the use of the insert, can also used to remove cap screws.
Claims (20)
1. A socket driver tool for a cap screw having a head with a central hexagonally shaped recess, the socket driver tool comprising;
a hollow cylindrical socket comprising an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the end wall within and in coaxial relationship with the cylindrical socket so as to fit within and cooperate with the central hexagonal recess in the head of the screw when the cylindrical socket is placed over the head of the screw.
a hollow cylindrical socket comprising an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the end wall within and in coaxial relationship with the cylindrical socket so as to fit within and cooperate with the central hexagonal recess in the head of the screw when the cylindrical socket is placed over the head of the screw.
2. The socket driver tool of claim 1 wherein the inner surfaces of the cylindrical socket are modified to define a roughened finish for engaging the head of the cap screw.
3. The socket driver tool of claim 2 wherein the roughened finish is in the form of striations running from the end wall to the open end for engaging the head of the cap screw.
4. A socket driver tool for a cap screw having a head with a central hexagonally shaped recess, the socket driver tool comprising;
a hollow cylindrical socket having an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, wherein the end wall defines a recess of predetermined shape therein, and a replaceable hexagonal key insert to be inserted into and driven by the recess in the end wall of the cylindrical socket, the insert comprising, a base which snugly fits into and remains in a single orientation within the predetermined shape of the recess in the end wall of the cylindrical socket, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the base so as to fit within and cooperate with the hexagonal recess in the head of the screw when the insert is placed within the recess in the end wall of the cylindrical socket and the cylindrical socket is placed over the head of the screw.
a hollow cylindrical socket having an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, wherein the end wall defines a recess of predetermined shape therein, and a replaceable hexagonal key insert to be inserted into and driven by the recess in the end wall of the cylindrical socket, the insert comprising, a base which snugly fits into and remains in a single orientation within the predetermined shape of the recess in the end wall of the cylindrical socket, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the base so as to fit within and cooperate with the hexagonal recess in the head of the screw when the insert is placed within the recess in the end wall of the cylindrical socket and the cylindrical socket is placed over the head of the screw.
5. The socket driver tool of claim 4 wherein the insert is held in the recess in the end wall of the cylindrical socket by a pin which is inserted through a bore in a side wall of the recess into an indentation in the base of the insert.
6. The socket driver tool of claim 4 wherein the insert is held within the recess in the end wall of the cylindrical socket by a d-dent pin on the base of the insert which cooperates with a bore through a side wall of the recess.
7. The socket driver tool of claim 4 wherein the predetermined shape of the recess in the end wall is selected to accept a hexagonal insert.
8. The socket driver tool of claim 4 wherein the replaceable hexagonal insert comprises:
a base which fits snugly into, remains in a single orientation within and is driven by the predetermined shape of the recess in the end wall of the cylindrical socket and wherein a central portion of the base has been modified to define a recess; and a replaceable hexagonal key portion comprising, a first end which conforms to, is held within and is driven by the recess in the base, and a second end, opposite the first end, which conforms to the central hexagonal recess in the head of the cap screw, and wherein when the insert is held within the recess in the end wall of the cylindrical socket and the key is held within the recess of the base, the opposite end of the key extends out from the base in coaxial relationship with the cylindrical socket so as to fit within and cooperate with the central hexagonal recess in the head of the cap screw when the socket is assembled and placed over the head of the cap screw.
a base which fits snugly into, remains in a single orientation within and is driven by the predetermined shape of the recess in the end wall of the cylindrical socket and wherein a central portion of the base has been modified to define a recess; and a replaceable hexagonal key portion comprising, a first end which conforms to, is held within and is driven by the recess in the base, and a second end, opposite the first end, which conforms to the central hexagonal recess in the head of the cap screw, and wherein when the insert is held within the recess in the end wall of the cylindrical socket and the key is held within the recess of the base, the opposite end of the key extends out from the base in coaxial relationship with the cylindrical socket so as to fit within and cooperate with the central hexagonal recess in the head of the cap screw when the socket is assembled and placed over the head of the cap screw.
9. The socket driver tool of claim 8 wherein the predetermined shape of the recess in the end wall is selected to accept a hexagonal insert.
10. The socket driver tool of claim 9 wherein the recess in the base is square, and the hexagonal key portion has a first end which conforms to and is held within the square recess in the base and a second end, opposite the first end, which conforms to the hexagonal recess in the head of the cap screw.
11. The socket driver tool of claim 8 wherein a pin is employed to hold the replaceable hexagonal key portion within the recess in the base and the pin is further employed to hold the base within the recess in the end wall of the cylindrical socket, wherein the pin passes through both a bore in a side wall of the recess in the end wall of the cylindrical socket and a bore in the base, when these bores are aligned, to enter an indentation in the end of the hexagonal key portion which is held within the base.
12. The socket driver tool of claim 8 wherein the insert is held within the recess in the end wall of the cylindrical socket by means of a d-dent pin on the base which cooperates with a bore through a side wall of the recess in the end wall of the cylindrical socket and the replaceable hexagonal key is held within the recess in the base by a d-dent pin on the key which cooperates with a bore in the base.
13. The socket driver tool of claims 4 or 8 wherein the inner surfaces of the cylindrical socket are modified to define a roughened finish.
14. The socket driver tool of claims 4 or 8 wherein the roughened finish is in the form of striations running from the recess in the end wall of the cylindrical socket to the open end for engaging the head of the cap screw.
15. A socket driver tool for a cap screw having a head with a central hexagonally shaped recess, the socket driver tool comprising;
a hollow cylindrical socket having an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, wherein the end wall defines therein a recess of predetermined shape and wherein there are splines disposed about the inner surfaces extending from the open end to the recess in coaxial relationship with the socket, a replaceable hexagonal key insert to be inserted into and driven by the recess in the end wall of the cylindrical socket, the insert comprising, a base which snugly fits into and remains in a single orientation within the predetermined shape of the recess in the end wall of the cylindrical socket, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the base so as to fit within and cooperate with the hexagonal recess in the head of the screw when the insert is placed within the recess in the end wall of the cylindrical socket and the cylindrical socket is placed over the head of the screw, and a spring means acting between the end wall and the insert to hold the insert toward the open end of the socket while allowing the insert to be pushed toward the end wall of the socket.
a hollow cylindrical socket having an end wall to which torque may be applied and an open end, opposite the end wall, the cylindrical socket adapted to snugly fit over and encapsulate the head of the cap screw so that inner surfaces of the cylindrical socket are able to contact the head of the screw, wherein the end wall defines therein a recess of predetermined shape and wherein there are splines disposed about the inner surfaces extending from the open end to the recess in coaxial relationship with the socket, a replaceable hexagonal key insert to be inserted into and driven by the recess in the end wall of the cylindrical socket, the insert comprising, a base which snugly fits into and remains in a single orientation within the predetermined shape of the recess in the end wall of the cylindrical socket, and a hexagonal key portion, corresponding to the hexagonal recess in the head of the cap screw, concentric with and extending from the base so as to fit within and cooperate with the hexagonal recess in the head of the screw when the insert is placed within the recess in the end wall of the cylindrical socket and the cylindrical socket is placed over the head of the screw, and a spring means acting between the end wall and the insert to hold the insert toward the open end of the socket while allowing the insert to be pushed toward the end wall of the socket.
16. The socket of claim 15 wherein the splines comprise cutting edges adjacent the open end of the socket for scoring the head of the screw as the socket is forced over the head of the screw.
17. The socket of claim 15 wherein the splines are disposed about the inner surfaces of the cylindrical socket so that the insert can be placed into and removed from the socket.
18. The socket of claim 15 wherein the insert is held in the recess in the end wall of the cylindrical socket by a d-dent pin on the base of the insert which cooperates with a slot through a side wall of the recess, wherein the slot is selected to be of a length adequate to allow the insert to move coaxially within the socket.
19. The socket driver tool of claim 15 wherein the recess is extended up the inner surfaces of the socket so that the insert can move coaxially with the socket and can be driven by the socket at any point along the socket.
20. The socket driver tool of claim 15 or 19 wherein the predetermined shape of the recess in the end wall is selected to accept a hexagonal insert.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2057104 CA2057104A1 (en) | 1991-12-05 | 1991-12-05 | Socket driver tool |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2057104 CA2057104A1 (en) | 1991-12-05 | 1991-12-05 | Socket driver tool |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2057104A1 true CA2057104A1 (en) | 1993-06-06 |
Family
ID=4148871
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2057104 Abandoned CA2057104A1 (en) | 1991-12-05 | 1991-12-05 | Socket driver tool |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2057104A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| USD992387S1 (en) | 2017-12-13 | 2023-07-18 | Apex Brands, Inc. | Extractor socket |
-
1991
- 1991-12-05 CA CA 2057104 patent/CA2057104A1/en not_active Abandoned
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| USD992387S1 (en) | 2017-12-13 | 2023-07-18 | Apex Brands, Inc. | Extractor socket |
| USD1036211S1 (en) | 2017-12-13 | 2024-07-23 | Apex Brands, Inc. | Extractor socket |
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| Date | Code | Title | Description |
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| EEER | Examination request | ||
| FZDE | Dead |