Patent Application
20090255386
1. Field of the Invention
The present invention relates to a wrench, and more particularly to a torque socket.
2. Description of the Prior Art
A conventional socket is normally mounted on a power tool or wrench to screw or unscrew a fastener, and the screwing or unscrewing force is manually controlled by the user. Too large force will cause damage to the fastener, and too small force may cause looseness of the fastener.
To solve the abovementioned drawbacks, normally, the socket is structurally designed to have a predetermined value which prevents the inappropriate force caused deadlock or looseness of the fastener.
For example, GB Patent No. 856136 discloses torque limiting wrench which comprises three smaller balls abutted against the lower end of a larger ball, an elastic member vertically pressing against the larger ball, and a cylindrical housing defined with slots for receiving the smaller balls. These parts cooperate with one another to screw and unscrew a fastener. However, the cylindrical housing is brought into contact with the smaller balls by smooth arc surfaces, in other words, there is no ratchet structure in the cylindrical housing, so that when the torque wrench is operated, it is too difficult to detect if the toque applied to the fastener by the torque wrench has reached the predetermined value, thus needing improvement. In addition, the torque wrench needs to be defined with multiple holes to cooperate with the respective elements, such as the larger ball, the three smaller balls, the elastic member, etc. Furthermore, the respective elements need to be produced independently, and it also requires holding spaces to be formed to hold the elements, so the production difficulty and cost are increased.
Further, U.S. Pat. No. 3,693,381 discloses torque responsive clutch which comprises a larger central ball under a predetermined spring pressure, three smaller balls abutted against the lower end of the larger central ball, and a hosing with six identical recesses. With these parts, the output torque of the wrench can be detected in time during the operation of the torque clutch. However, such a conventional torque responsive clutch also has the above drawbacks of difficult to detect if the toque applied to the fastener by the torque wrench has reached a predetermined value, complicated machining procedure, and high production difficulty and cost.
GB Patent No. 2180476 discloses quick change adapter with a torque limiter for a tapping chuck which comprises a tap holder, a driving element, a casing and an inner toque means. These parts cooperate with one another to allow the fastener to be appropriately screwed or unscrewed. However, the torque means includes plural pairs of balls that cooperate with a plain washer and plural Belleville type springs, the torque limiter need to be defined with multiple holes to cooperate with the respective elements, thus increasing assembly difficulty and the production cost.
In addition, U.S. Pat. No. 4,063,474 discloses torque limiting screwdriver which essentially comprises a sliding sleeve, a torque adjusting rod and a torque adjusting means therein. The torque adjusting means includes plural balls, a clutch and plural springs. Since the configuration is complicated, multiple holes need to be defined to cooperate with the respective elements, and the respective elements need to be produced independently, and it also requires holding spaces to be formed to hold the elements, the production difficulty and cost of the torque socket are greatly increased. Further, it is also too difficult to detect if the torque applied to the fastener by the torque wrench has reached a predetermined value, so improvement is also needed.
Finally, U.S. Pat. No. 4,272,973 discloses socket joint for torque wrench which is orderly provided with a first engaging element, a second engaging element to be engaged with the first engaging element, a spring pressing against the second engaging element and an adjusting bolt pressing against the spring in a housing. When the toque joint is in use, once the force applied by the spring to the second engaging element is insufficient, idle rotation of the second engaging element will be caused, and the torque joint will become ineffective.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.
The primary objective of the present invention is to provide a torque socket, which utilizes an inner ratchet structure to produce a sound when the torque has reached a predetermined value, allowing the user to easily detect that the torque applied by the torque wrench to the fastener has reached the predetermined value.
The secondary objective of the present invention is to provide a torque socket which is simple in structure, thus reducing the production and assembly cost.
Hence, in order to achieve the above objectives, a torque socket in accordance with the present invention comprises an inner socket and an outer socket. The inner socket is interiorly provided with an axially movable positioning ball, a spring and a radially movable loading ball, the positioning ball and the loading ball are pushed against each other, and the loading ball is allowed to partially protrude out of the inner socket.
The outer socket axially includes a holding groove in one end thereof, the holding groove of the outer socket is formed with a ratchet surface on an inner periphery thereof, on the ratchet surface is equidistantly provided plural annularly-arranged teeth, the respective teeth include two side surfaces, and a resisting surface connected between the two side surfaces, between two opposite side surfaces of each two neighboring teeth is formed a U-shaped engaging recess with respect to the ratchet surface, the outer socket is allowed to be pivotally engaged on the inner socket, when the loading ball is engaged into the one of the engaging recesses, the outer socket and the inner socket will be fixed relative to each other, when the loading ball is pushed against by one of the resisting surfaces of the teeth, the outer socket and the inner socket are allowed to pivot relative to each other.
By such arrangements, during a pivoting process of the inner socket and outer socket, the loading ball will move into and out of the inner socket due to its position changes with respect to the engaging recesses and the teeth, and when the loading ball passes over the teeth and engages into the engaging recess, a sound will be produced.
The present invention will be clearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention.
Referring to
The inner socket 20 axially includes a recess 21 and a first assembling portion 22 in two opposite ends thereof. The inner socket 20 is radially defined with a through hole 23 in communication with the recess 21. Further, the inner socket 20 is formed with a flange 24 radially extending outwards from a middle portion thereof. In addition, between the recess 21 and the first assembling portion 22 is axially defined a threaded adjusting hole 25. A positioning ball 41, a first stopper 42, a spring 43 and a second stopper 44 are orderly disposed in the recess 21 and abutted against one another. The first assembling portion 22 is an inner tetragonal or hexagonal groove for engaging with a tool head D (as shown in
The outer socket 30 axially includes a holding groove 31 and a second assembling portion 32 at two ends thereof. The second assembling portion 32 is provided for engaging with hand tools such as a wrench A or a gripping handle B (as shown in
By such arrangements, during the pivoting process of the inner socket 20 and outer socket 30, the loading ball 45 will move into and out of the inner socket 20 due to its position changes with respect to the engaging recesses 35 and the teeth 33, and when the loading ball 45 passes over the teeth 33 and engages into the engaging recess 35, a sound will be produced.
The aforementioned is the key technology and the summary of the positional and structural relationship of the respective components of the preferred embodiment in accordance with the present invention.
For a better understanding of the present invention, its operation and function, reference should be made to
When the torque applied to the torque socket during operation is lower than the value preset by the user, the torque socket can be used to screw or unscrew the fastener due to secure engagement between the loading ball 45 and one of the engaging recesses 35 of the outer socket 30.
When the torque applied to the torque socket during operation is greater than the value preset by the user, the outer socket 30 can be rotated in a clockwise direction to allow the loading ball 45 to retract into the through hole 23 of the inner socket 20 along the first side surface 331 and the resisting surface 333 of one of the teeth 33 of the outer socket 30. At this moment, the loading ball 45 will push the positioning ball 41 to ascend a certain distance. Upon ascending, the positioning ball 41 will compress the spring 43. After that, the outer socket 30 is continuously rotated, so that when the engaging recess 35 of the outer socket 30 is aligned with the loading ball 45, the loading ball 45 will be biased toward the corresponding engaging recess 35 from the resisting surface 333 of the tooth 33 by the elastic force of the spring 43 and quickly engaged into the engaging recess 35, that is to say, the loading ball 45 is restricted in the space defined by the second side surface 332 of one of the teeth 33, the first side surface 331 of the neighboring tooth 33 and the ratchet surface 311 of the outer socket 30. Therefore, while the loading ball 45 quickly touches the second side surface 332 of the one of the teeth 33, the first side surface 331 of the neighboring tooth 33 and the ratchet surface 311 of the outer socket 30, the sound will thus be produced. As a result of this, when the torque achieves the predetermined value during the operation of the toque socket, the sound will be produced to warn the user that the torque applied to the fastener by the toque wrench has reached the predetermined value.
The torque socket in accordance with the present essentially comprises an outer socket, an inner socket, a spring, a positioning ball and a loading ball, so that the present invention is simple in structure. Especially, only one set of a positioning ball and a loading ball is needed, so the present invention is more convenient to assemble.
Referring to
Referring to
Referring to
While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 097113531 | Apr 2008 | TW | national |
