Patent ID: 12246415

EMBODIMENT FOR CARRYING OUT THE INVENTION

One embodiment of a socket adapter for the impact wrench (hereinafter referred to as “socket adapter”)10of the present invention will be described below with reference to the drawings.

InFIGS.1and2, (a) is a cross-sectional view and (b) is a side elevation view of the socket adapter10according to one embodiment of the invention.FIG.1shows a locked state wherein a ball51protrudes and a socket80shown inFIG.1(a)cannot be detached.FIG.2shows an unlocked state wherein the ball51retracts and the socket80can be attached and detached.

As shown inFIGS.1and2, the socket adapter10has a main body11that comprises a cylinder section20formed on the impact wrench side and configured to fit on an insertion square90(shown inFIG.1(a)), a shank section40configured for the socket to be attached (shown inFIG.1(a)), and a drum section30positioned between the cylinder section20and the shank section40.

The cylinder section20on the impact wrench side is formed with an engagement hole21into which the prismatic insertion square90(also named “anvil”) of impact wrench is insertable, as shown inFIG.1(a). The socket adapter10and the insertion square90are detachably connected by, for example, a pin locking mechanism25.

In more detail, as shown inFIG.1(a), the pin locking mechanism25is configured to install the socket adapter10on the insertion square90by aligning a pin inserting hole91opened orthogonally to the axis center of the insertion square90, with a pin inserting hole22opened orthogonally to the engagement hole21in the socket adapter10, and then inserting a pin26in the pin inserting holes22,91. To prevent the pin26from falling out of the pin inserting holes22,91, the cylinder section20is formed on its outer periphery with a circumferential groove23extending over an open end of the pin inserting hole22, and an O-ring27is fitted in the circumferential groove23. An O-ring retreating groove24is formed next to the peripheral groove23, and the insertion and removal of the pin26can be performed by migrating the O-ring27to the O-ring retreating groove24.

A socket80is detachably provided on the forward end of the socket adapter10, as shown inFIG.1(a). The socket adapter10comprises a ball locking mechanism50that serves to attach or detach the socket80.

The ball locking mechanism50is configured to hold the socket80detachably by protrusion or retraction of a ball51in the shank section40. The socket80is formed with a locking hole81into which the ball51is fitted. The locking hole81can be shared with a pin inserting hole where pin26of the pin locking mechanism25is inserted when the socket80is attached directly to the insertion square90.

The socket adapter10has an insertion hole41in the axial direction from the shank section40to the drum section30. The shank section40is formed on its side surface with a ball accommodation hole42orthogonal to and reaching the insertion hole41. A ball51is housed in the ball accommodation hole42and capable of partially protruding from a reduced diameter edge of the ball accommodation hole42.

A push rod52is slidably accommodated in the insertion hole41and configured to control protruding and retracting of the ball51. The push rod52is formed at different levels on its side surface with an unlocking groove53having a deep groove depth and a locking groove54having a shallow groove depth. In the illustrated embodiment for the push rod52, the unlocking groove53is formed on its base end side, and the locking groove54is formed on a forward end side.

FIG.1(a)shows a position where the push rod52has moved to the base end side of the insertion hole41. This position is in a locked state wherein the locking groove54with a shallow groove depth contacts the ball51, and the ball51partially protrudes from the ball accommodation hole42and cannot retract. In the locked state, the ball51enters the locking hole81of the socket80, so that the socket80cannot be detached from the socket adapter10.

On the other hand,FIG.2(a)shows a position where the push rod52is moved to the forward end side of the insertion hole41. This position is in an unlocked state wherein the unlocking groove53with a deep groove depth faces the ball51, and the ball51can retract into ball accommodation hole42. In the unlocked state, the ball51retracts into the ball accommodation hole42, so that the socket80can be attached and detached.

The push rod52mentioned above has a mounting pin57provided on the base side thereof and extending vertically through the push rod52, as shown inFIGS.1(a) and2(a). The push rod52is formed on the forward end side than the mounting pin57with a flange55to provide a step-shaped portion32in the insertion hole41. A biasing member56is installed between the flange55and the step-shaped portion32. An example of the biasing member56can be a compression spring, which forces the push rod52toward the base end side. In the unloaded state, the push rod52is held in the locking position where the locking groove54contacts the ball51, as shown inFIG.1(a).

The drum section30is formed on its side surface with a hole31into which the pin57is fitted. The hole31may be in the form of round hole, elongated hole, etc. The hole31is formed along the axial direction of the socket adapter10on the side surface of the drum section30and is long enough to allow the push rod52to slide between the locking position and the unlocking position.

The drum section30has a manipulator ring60provided for sliding the push rod52from the locking position to the unlocking position, as shown inFIGS.1and2. In the illustrated embodiment, the manipulator ring60is provided on the forward end side thereof with a manipulating part61having a periphery protruding outward slightly to make it easy for the user to operate with fingers. The manipulator ring60is formed on the base end side than the manipulating part61with holes62opposite each other to insert the mounting pin57therethrough and engage therewith. The drum section30is formed in the peripheral surface thereof with a recessed groove63extending through an opened end of the mounting pin57. A pin removal preventing member64is fitted in the recessed groove63to prevent the mounting pin57from falling out of the manipulator ring60. The pin removal preventing member64as illustrated is a coiled spring, but may be an annular-shaped plate spring, O-ring, or other fixture device.

In the unloaded state, the manipulator ring60is urged toward the locking position on the base end side (cylinder section20side) by the biasing member56for biasing the push rod52, as shown inFIG.1. When the user operates from this state to push the manipulating part61toward the forward end, the manipulator ring60moves against the force from the biasing member56.

The biasing member56applies a constant force to the manipulator ring60toward the locking position. So, if the force is weak, the manipulator ring60will likely move easily to the unlocking position due to vibration of the impact wrench or collision with an obstacle. Therefore, the biasing member56requires force enough to prevent the manipulator ring60from moving.

However, the user must keep fingers on the manipulator ring60while attaching the socket80to or detaching the socket80from the adapter10. If the force exerted on the push rod52from the biasing member56is large, the user must keep firm pressure on the manipulator ring60. In addition, the user needs to grasp the socket80with one hand when attaching the socket80to or detaching the socket80from adapter10. Therefore, the user must hold the manipulator ring60and the impact wrench with one hand, while pressing the manipulator ring60with fingers. It is not convenient to operate if a large force is constantly exerted on the manipulator ring60from the biasing member56.

The manipulator ring60requires such a configuration that makes it resistant for the manipulator ring60to slide only at the point where it is started from the locking position to the unlocking position, without a strong force constantly acting on the manipulator ring60. The manipulator ring60also requires in the unlocking position beyond the starting point such a configuration that the user can slide it smoothly while depressing only by light force.

In the light of the above-mentioned requirements, the present invention provides a means70for imparting a starting resistance that increases the resistance of the manipulator ring60when it begins to start. The starting resistance imparting means70is configured to provide a larger starting resistance to the manipulator ring60only at the starting point of moving the manipulator ring60from the locking position to the unlocking position, and beyond the starting point, not to provide a resistance to the sliding movement of the manipulator ring60.

One embodiment of the starting resistance imparting means70is shown inFIG.1(a), wherein the drum section30has a groove33formed in the forward end side of the manipulator ring60and running circumferentially around the drum section30. A spring ring71is wound around the groove33. The spring ring71may be a C-shaped spring with a restoring force in the direction of spreading outward, as indicated by arrows inFIG.3.

An enlarged view of the groove33is shown inFIG.4(a). As illustrated, the groove33is formed at a position that overlaps the forward end of the manipulator ring60when the manipulator ring60is in the locking position. The groove33has a depth equal to or larger than the wire diameter of the spring ring71, and the outer peripheral surface of the spring ring71is compressed by the manipulator ring60, as shown inFIG.4(b), so that the manipulator ring60is retractable in the groove33.

As shown inFIGS.1(a) and4(a), the manipulator ring60is formed in its inner surface on the forward end side with a tapered surface65inclined to expand an inner diameter of the manipulator ring60toward the forward end side such that the spring ring71is compressed.

In operation, as shown inFIGS.1(a) and4(a), the spring ring71is loaded in the groove33in such a state that it is pressed inwardly against the restoring force. The manipulator ring60is fitted on the drum section30for the tapered surface65to face the spring ring71and groove33. In the locking position, the outer peripheral surface of the spring ring71protrudes from the groove33and contacts the tapered surface65of the manipulator ring60. Then, the spring ring71contacts the manipulator ring60and prevents the manipulator ring60from moving to the unlocking position. Therefore, when the socket80is attached to the adapter10, the ball51fits into the locking hole81of the socket80, and the socket80remains undetachable.

From this position, the user pushes the manipulating part61toward the distal end side of the socket adapter10, as shown by the arrow inFIG.1, to move the manipulator ring60to the unlocking position. In the locking position, as shown inFIG.4(a), the outer peripheral surface of the spring ring71protrudes from the groove33in the manipulator ring60. Therefore, to move the manipulator ring60to the unlocking position, the spring ring71must be compressed to reduce its outer diameter. The force for compressing the outer diameter of the spring ring71is the starting resistance of the manipulator ring60. This starting resistance acts only on the starting point that allows the manipulator ring60to move from the locking position to the unlocking position.

In more particular, when the user moves the manipulator ring60in the direction of the arrow inFIG.1(a), the outer peripheral surface of the spring ring71is compressed inwardly by the tapered surface of the manipulator ring60and is fitted into the groove33. At this time, the manipulator ring60is also subjected to a biasing force from the biasing member56in the direction of returning to the locking position.

To perform this operation, the user needs to apply a strong force to the manipulator ring60at the starting point. This force is sufficient to prevent the manipulator ring60from moving from the locking position even if the user comes in contact with an obstacle or the impact wrench vibrates. Hence, the manipulator ring60does not move from the locking position, so the socket80is prevented from being unintentionally detached from the adapter10.

As the user further operates to push the manipulator ring60forward, as shown inFIG.2(a)andFIG.4(b), the tapered surface65goes over the spring ring71, and the outer peripheral surface of the spring ring71comes into sliding contact with the inner surface of the manipulator ring60. Since this sliding resistance is minimal compared to the starting resistance, the force acting on the manipulator ring60is, in effect, only the force received from the biasing member56that enforces the push rod52. As described above, the force applied from the biasing member56is relatively small, so the user can smoothly move the manipulator ring60to the unlocking position. This allows the user to keep the manipulator ring60pushing against the biasing member56while holding the impact wrench with one hand.

In this state, the ball locking mechanism50allows the ball51to retract, so the user can operate to attach and detach the socket80with one hand.

When the user detaches the socket80and releases the force applied on the manipulator ring60, the manipulator ring60and the push rod52move toward the locking position by the force of the biasing member56. When the tapered surface65of the manipulator ring60faces the spring ring71, the spring ring71contacts the tapered surface65by a restoring force of spreading outward and forces the manipulator ring60toward the locking position in a combined power with the biasing member56. Thus, the user can reliably return the manipulator ring60to the locking position. The ball locking mechanism50preserves the locked state wherein the ball51is protruding, as shown inFIG.1.

As described above, the present invention provides the starting resistance imparting member70that increases only the starting resistance of the manipulator ring60. Therefore, in the state where the socket80is attached to the shank section40of the adapter10, the manipulator ring60does not move even if the user comes in contact with an obstacle or the impact wrench vibrates, so that the socket80is prevented from being unintentionally detached from the adapter10. In addition, the increased resistance is applied only at the starting point, and the subsequent operation for sliding the manipulator ring60can be performed with only a small power, so that the user can handle the manipulator ring60with one hand. Therefore, even when the impact wrench is used at a high altitude, the user can safely attach the socket80to and detach the socket80from the adapter10.

The above description is for the purpose of explaining the present invention, and should not be construed as limiting the scope of the invention described in the claims. In addition, each part of the present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made within the technical scope described in the claims.

In the above embodiment, the user operates to push the manipulator ring60toward the distal end side of the adapter10to unlock the ball lock mechanism50. However, the ball locking mechanism50can be unlocked by pulling the manipulator ring60toward the impact wrench side of the adapter10. In this case, the starting resistance imparting means70can be configured to provide a starting resistance when the manipulator ring60moves toward the impact wrench side of the adapter10

EXPLANATION OF REFERENCE NUMBERS

10Socket adapter11Main body20Cylinder section21Engagement hole30Trunk section33Groove40Shank section50Ball locking mechanism51Ball70Starting resistance imparting means71Spring ring80Socket90Insertion square