Patent Description:
An implant denotes a replacement for restoring lost human tissue. In the field of dentistry, the implant in general denotes a replacement that is used to restore the original function of a tooth by implanting and adhering a fixture in an alveolar bone from which a root of a natural tooth has been lost, connecting an abutment to the top of the fixture, and fixing a crown on the abutment.

As such an implant for a dental implant procedure, the most common is a screw-type, in which an abutment and a fixture are fastened together by means of clamping force of a screw. This screw-type implant is composed of a fixture, an abutment, and a prosthesis.

In the procedure for the screw-type implant, in a conventional method, fastening or unfastening of the fixture and the abutment with the screw is performed by using both a separate hand driver and a conventional torque wrench for implant procedures that can firmly tighten a screw with a specific torque.

When fastening or unfastening with a screw using the conventional torque wrench, the torque wrench can be used only after a male screw is engaged to a corresponding female screw. In particular, when the male screw is tightened with the torque wrench in a state in which the male screw and the female screw are not engaged or are not fully engaged, there is a problem in that the torque wrench may not rotate properly and fail to fasten the screws. Due to this problem, when fastening with a screw, the screw has to be first tightened to a certain degree with the separate hand driver rather than the torque wrench, and then firmly tightened again with the torque wrench to prevent the screw from being loosened due to continuously applied masticatory pressure. Likewise, when loosening the firmly tightened screw, the screw has to be loosened with the torque wrench to a certain degree, and then finally the hand driver has to be used again for complete removal, which is a cumbersome process.

During a dental implant procedure, when a fastening site where an abutment and a fixture are fastened is located deep inside the oral cavity, an operator first has to tighten a screw to a certain degree with the hand driver in one hand while opening a patient's mouth with the other hand, and then the hand driver has to be replaced with the torque wrench to firmly tighten the screw with a high torque. In particular, in the case of a patient whose mouth is hard to open, it may not easy to accurately position and tighten the hand driver directly on the fastening site in the oral cavity. In some cases, the operator may accidentally drop the driver in the oral cavity.

Document <CIT> shows a torque wrench for installing dental prosthesis, the torque wrench comprising a ratchet shaft within a tubular torque transmitting shaft.

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an objective of the present invention is to provide a torque wrench, wherein only a single torque wrench according to the present invention is necessary to first tighten a screw and finally firmly fasten the screw with a desired force or to first loosen the screw and finally completely remove the screw, even without the use of a separate hand driver, thereby making it possible to reduce discomfort that a patient has to open his/her mouth excessively during a procedure, or that an operator needs to use his/her hand to tighten the screw at a site where access is difficult.

Another objective of the present invention is to provide a torque wrench that is configured to enable a screw to be efficiently fastened and removed with only a single torque wrench, thereby enabling a more precise and stable procedure, as well as shortening a procedure time.

Still another objective of the present invention is to provide a torque wrench capable of eliminating cumbersome operation of having to provide a hand driver and a torque wrench at the same time and having to exchange the driver for the wrench during a procedure of fastening or removing a screw.

Still another objective of the present invention is to provide a torque wrench that does not require the use of a hand driver, thereby preventing the problem that a patient may swallow the hand driver.

In order to accomplish the above objective, according to one aspect of the present invention, there is provided a torque wrench for an implant procedure, the torque wrench comprising: a first body part having a predetermined length, and including a hollow portion formed in a longitudinal direction and a head portion in which a fastening hole is formed at an end thereof to which a torque wrench driver bit is coupled; a rotor having a first gear provided at an upper end of the rotor, the rotor being inserted into a fastening hole formed in the head portion, the rotor having a plurality of ratchet grooves formed in an outer surface thereof; a first shaft including a ratchet protrusion formed at one end thereof and configured to be inserted into the hollow portion of the first body such that the ratchet protrusion is coupled to the ratchet grooves to enable one-way torque transmission; at least one second body part having a predetermined length, provided at the upper side of the first body part, and including a coupling portion formed in a longitudinal direction thereof; and a second shaft rotatably coupled to the coupling portion of the second body part, including a second gear provided at one end thereof and a knob provided at the other end thereof, and configured such that, in response to rotation of the knob, the second shaft transmits torque to the rotor and to the torque wrench driver bit through the first gear engaged with the second gear.

Preferably, the first gear may be rotatably provided at an upper side of the torque wrench driver bit or at one side of the head portion of the first body part.

Most preferably, the torque wrench may further include a bar-shaped torque gauge provided at one side of the first body part.

Preferably, the torque wrench may further include a protective cover protecting a portion where the first gear and the second gear are engaged with each other from being exposed externally.

According to the present invention, the following effects are provided.

First, it is possible to first tighten the screw and finally firmly fasten the screw or to loosen the screw and completely remove the screw by using only a single torque wrench according to the present invention, even without the use of a separate hand driver. This makes it possible to prevent the problem that an operator may accidentally drop the driver and a patient may swallow the driver during a procedure.

Second, the present invention is configured to enable a screw to be efficiently fastened and removed with only a single torque wrench, thereby enabling a more precise and stable procedure, as well as to shortening a procedure time.

Third, it is possible to eliminate cumbersome operation of having to provide a hand driver and a torque wrench at the same time and having to exchange the driver for the wrench during a procedure of fastening or removing a screw.

Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

<FIG> is a perspective view illustrating a torque wrench according to an embodiment of the present invention, and <FIG> is an exploded perspective view illustrating the torque wrench according to the embodiment of the present invention. Referring to <FIG> and <FIG>, a torque wrench for an implant procedure according to an embodiment of the present invention includes: a first body part <NUM> having a predetermined length, and including a head portion <NUM> in which a fastening hole <NUM> is formed at an end thereof to allow a torque wrench driver bit <NUM> to be detachably coupled thereto; at least one second body part <NUM> having a predetermined length, provided at one side of the first body part <NUM>, and including a coupling portion formed in a longitudinal direction thereof; and a second shaft <NUM> rotatably coupled to the coupling portion of the second body part <NUM>, including a second gear <NUM> provided at one end thereof and a knob <NUM> provided at the other end thereof, and configured such that, in response to rotation of the knob <NUM>, the second shaft transmits torque to the torque wrench driver bit <NUM> through the first gear <NUM> engaged with the second gear <NUM>.

As illustrated in <FIG>, the first body part <NUM> includes the head portion <NUM> in which the fastening hole <NUM> is formed at one end thereof, and the fastening hole <NUM> of the head portion <NUM> allows the torque wrench driver bit <NUM> to be detachably coupled thereto. The first body part <NUM> may be configured such that the torque wrench driver bit is rotatable only in one direction by the operation of rotation direction control knobs <NUM> and <NUM>.

The at least one second body part <NUM> is provided at one side of the first body part <NUM> at a predetermined length along a longitudinal direction of the first body part <NUM>, with the coupling portion formed in the longitudinal direction thereof. Here, the coupling portion may be implemented in any form to which the second shaft can be rotatably coupled, preferably in the form of a hollow portion, and may be configured such that one side between opposite ends thereof is open externally.

The second shaft <NUM> is coupled to the coupling portion of the second body part <NUM>, and is configured such that, in response to rotation of the knob <NUM> provided at the other end thereof, the second shaft transmits torque to the torque wrench driver bit <NUM> fastened to the fastening hole <NUM>, through the second gear <NUM> formed at the end of the second shaft <NUM> and the first gear <NUM> engaged with the second gear <NUM>. Preferably, the first gear <NUM> is a first bevel gear, and the second gear <NUM> is a second bevel gear. In some cases, as illustrated in <FIG>, the first and second gears may be implemented as worm gears. Meanwhile, <FIG> and <FIG> illustrate that the first gear <NUM> is formed at an upper end of the torque wrench driver bit <NUM>, but the present invention is not limited thereto. Therefore, it should be interpreted as a concept including a gear with arbitrary position and structure, the gear being capable of transmitting torque to the torque wrench driver bit <NUM> by engagement with the second gear <NUM>. For example, there may be provided a rotor integrally coupled to the head portion of the first body part <NUM> so as to be rotatable, and including a first gear formed at an upper end thereof.

A hollow portion is further formed in the first body part <NUM> in the longitudinal direction thereof, and the first shaft <NUM> formed such that a ratchet protrusion <NUM> protrudes at one end thereof is inserted into the hollow portion of the first body part <NUM>, and the ratchet protrusion <NUM> is coupled to the torque wrench driver bit <NUM> so as to transmit torque thereto in one direction.

That is, as illustrated in <FIG>, a plurality of ratchet grooves <NUM> are formed in an outer surface of the torque wrench driver bit <NUM>, so that the ratchet protrusion <NUM> protruding at one end of the first shaft <NUM> may be coupled to the ratchet grooves <NUM> to enable one-way torque transmission.

Preferably, the structure and shape of the torque wrench driver bit <NUM> and the fastening hole <NUM> may also be variously modified.

More preferably, the other end of the first shaft <NUM> is provided with the rotation direction control knob <NUM> that can determine the rotation direction of the torque wrench, and the other end of the second shaft <NUM> is provided with the knob <NUM>. In some cases, the provision of the rotation direction control knob <NUM> that can determine the rotation direction of the torque wrench may be eliminated. To change the rotation direction of the torque wrench in the absence of the rotation direction control knob <NUM>, the torque wrench driver bit fastened to the fastening hole of the torque wrench can be fastened in the reverse direction and then rotated. Therefore, when fastening a screw using the torque wrench according to the present invention, the knob <NUM> is rotated to tighten the screw to a certain degree through the torque wrench driver bit, and then the rotation direction control knob <NUM> or the first body part <NUM> is rotated to rotate the torque wrench driver bit, thereby firmly fastening the screw. Furthermore, when removing the fastened screw, the rotation direction control knob <NUM> or the first body part <NUM> is rotated to release firm fastening, and then the knob <NUM> is rotated to completely remove the screw. Therefore, it is possible to first tighten the screw and finally firmly fasten the screw or to loosen the screw and completely remove the screw by using only a single torque wrench according to the present invention, even without the use of a separate hand driver tool.

Furthermore, a torque wrench for an implant procedure according to another embodiment of the present invention may be configured such that the above-described torque wrench driver bit <NUM> is integrally provided with the head portion <NUM> of the first body part <NUM>.

<FIG> is a perspective view illustrating a torque wrench according to another embodiment of the present invention, and <FIG> is an exploded perspective view illustrating the torque wrench according to the embodiment of the present invention. Referring to <FIG> and <FIG>, a first body part <NUM> includes a head portion <NUM> in which a fastening hole <NUM> is formed at one end thereof, a rotor <NUM> is integrally coupled to the fastening hole <NUM> of the head portion <NUM> so as to be rotatable, and a plurality of ratchet grooves <NUM> is formed in an outer surface of the rotor. Furthermore, a first gear is formed at an upper end of the rotor.

Furthermore, at least one second body part <NUM> is provided at one side of the first body part <NUM> at a predetermined length, and includes a coupling portion formed in a longitudinal direction thereof and to which a second shaft <NUM> is coupled. Preferably, the coupling portion may be in the form of a hollow portion. In <FIG> and <FIG>, two second body parts <NUM> are configured such that respective hollow portions thereof are arranged along longitudinal directions thereof, but the present invention is not limited thereto. Therefore, it should be interpreted as a concept including all forms as long as the second shaft can be coupled to the coupling portion of the second body part so as to be rotatable, regardless of the number, length and structure of the second body part.

The second shaft <NUM> is rotatably coupled to the coupling portion of the second body part <NUM>, and is configured such that, in response to rotation of a knob <NUM> provided at the other end thereof, the second shaft transmits torque to the rotor <NUM> and/or a torque wrench driver bit <NUM> fastened to the fastening hole <NUM>, through a second gear <NUM> formed at one end of the second shaft <NUM> and the first gear <NUM> engaged with the second gear <NUM>. The rotor <NUM> may be rotatably coupled to the fastening hole <NUM> by a fixing piece <NUM>. Preferably, the first gear <NUM> is formed at the upper end of the rotor <NUM>, and the torque wrench driver bit <NUM> is fitted to the rotor <NUM>. The first gear <NUM> is coupled to the second gear to transmit torque to the torque wrench driver bit <NUM>. <FIG> and <FIG> illustrate a structure in which torque is transmitted to the torque wrench driver bit <NUM> via the rotor <NUM>. However, the present invention is not limited thereto. Therefore, it should be apparent for those skilled in the art that the first gear <NUM> can be modified and applied to the head portion <NUM> of the first body part <NUM> in various shapes and/or structures.

Referring to <FIG> and <FIG>, the present invention further includes a protective cover <NUM> protecting a portion where the first gear <NUM> and the second gear <NUM> are engaged with each other from being exposed externally. This is to prevent foreign substances or the like from being introduced into the gap between the gears during the procedure, resulting in malfunction or danger. The present invention further includes a shaft cover <NUM> provided at an upper side of the second body part <NUM> to prevent the second shaft <NUM> from being exposed externally.

Furthermore, as illustrated in <FIG>, the present invention may further include bar-shaped torque gauges <NUM> and <NUM> provided at one sides of the first body parts <NUM> and <NUM>, respectively. In some cases, the bar-shaped torque gauges may be implemented in a curved shape.

Claim 1:
A torque wrench for an implant procedure, the torque wrench comprising:
a first body part (<NUM>, <NUM>) having a predetermined length, and including a hollow portion formed in a longitudinal direction and a head portion (<NUM>, <NUM>) in which a fastening hole (<NUM>) is formed at an end thereof to which a torque wrench driver bit (<NUM>, <NUM>) is coupled;
a rotor (<NUM>, <NUM>) having a first gear (<NUM>, <NUM>) provided at an upper end of the rotor, the rotor being inserted into a fastening hole (<NUM>, <NUM>) formed in the head portion (<NUM>, <NUM>),
the rotor having a plurality of ratchet grooves (<NUM>, <NUM>) formed in an outer surface thereof;
a first shaft (<NUM>, <NUM>) including a ratchet protrusion (<NUM>) formed at one end thereof and configured to be inserted into the hollow portion of the first body (<NUM>, <NUM>) such that the ratchet protrusion (<NUM>) is coupled to the ratchet grooves (<NUM>, <NUM>) to enable one-way torque transmission;
at least one second body part (<NUM>, <NUM>) having a predetermined length, provided at the upper side of the first body part (<NUM>, <NUM>), and including a coupling portion formed in a longitudinal direction thereof; and
a second shaft (<NUM>, <NUM>) rotatably coupled to the coupling portion of the second body part (<NUM>, <NUM>), including a second gear (<NUM>, <NUM>) provided at one end thereof and a knob (<NUM>, <NUM>) provided at the other end thereof, and configured such that, in response to rotation of the knob (<NUM>, <NUM>), the second shaft (<NUM>, <NUM>) transmits torque to the rotor and to the torque wrench driver bit (<NUM>, <NUM>) through the first gear engaged (<NUM>, <NUM>) with the second gear (<NUM>, <NUM>).