Patent Description:
There are various tools such as box-ended wrenches, open-ended wrenches, torque-adjustable wrenches, Allen keys, socket wrenches and related components. Pressing or printing is often used to provide a tool with an inscription to show a trademark, an aesthetic pattern or the size of the tool.

The use of the above-mentioned processes to make the inscription is not without any problem particularly where the inscription is used to show the size of the tool. For example, a user may have to wipe grease from the tool to read the inscription to know the size of the tool for the inscription is often covered entirely or partially by grease. Moreover, the user may have to flip the tool over to read the inscription since the inscription is often provided on a lower face of the tool in an operative position.

<CIT> discloses a tool-identifying system in which a color chart shows a range of ten colors and each color indicates a particular numeral. A sequence of indicated numerals represents the value of the size of a tool, in fractional inch or metric size. However, a user has to memorize the correspondence of the colors to the numerals. The user will experience troubles in picking bits of the right sizes might if he or she forgets the correspondence. Accordingly, the user may bring bits of wrong sizes to a working site and fail a task. Alternatively, the user may be forced to bring bits of all sizes to the working site, and this is quite a burden. In operation, the user may pick bits of wrong sizes before getting the bit of the right size, and this is a waste of time.

Document <CIT> discloses an adjustable wrench including a handle, a jaw formed on the handle, another jaw movably connected to the handle, a scale in fractional inch, and another scale in metric size. Each scale provides the correspondence of the value of each size to an actual with of a gap between the jaws. However, the scales could be covered with grease or steins.

Document <CIT> discloses a wrench according to the preamble of claim <NUM> with comprising a handle and a head attached to the handle, wherein the head includes a body and a worm gear, said body comprising a stationary jaw and a movable jaw, wherein a distance between the jaws is adjustable and lockable, wherein a triangular pointer is formed on a side of the movable jaw, and wherein multiple numbers and lines are indicated on a side of the body, wherein, when the distance between the jaws is set, the pointer points at the number corresponding to the distance between the jaws.

From document <CIT>, a reversible monkey wrench is known, which includes a handle and a head attached to the handle, wherein the head includes a body and a worm gear, said body comprising a stationary jaw and a movable jaw, wherein a distance between the jaws is adjustable and lockable, wherein a pointer is provided on a side of the movable jaw, and wherein multiple numbers and lines are indicated on a side of the body, wherein, when the distance between the jaws is set, the pointer points at the number and line corresponding to the distance between the jaws.

Document <CIT> shows another conventional wrench, comprising a handle and a head attached to the handle, wherein the head includes a body and a worm gear, said body comprising a stationary jaw and a movable jaw, wherein a distance between the jaws is adjustable, wherein a pointer is formed on a side of the movable jaw, wherein multiple numbers and lines are indicated on a side of the body, wherein, when the distance between the jaws is set, the pointer points at the number and line corresponding to the distance between the jaws, and wherein the wrench is further equipped with a device for warning, if a value of torque exceeds a maximum value.

Moreover, no wrench has been provided with anything to let a user know an adequate value of torque to be imposed on a workpiece such as a nut and a threaded bolt without causing damages to the workpiece. Hence, the user might not exert an inadequate value of torque to engage a nut with a threaded bolt so that the nut could easily be disengaged from the threaded bolt because of vibration.

The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.

It is the primary objective of the present invention to provide a torque-adjustable wrench using colors for identification.

To achieve the foregoing objective, a torque-adjustable wrench according to claim <NUM> is provided, which includes multiple color marks and a pointer in addition to a body and a movable jaw. The body includes a stationary jaw extending from a front end. The movable jaw is movably connected to the front end of the body so that a distance between the jaws is adjustable. The color marks are formed on a side of the body. Each of the color marks is in a color corresponding to a size of a workpiece. The pointer is formed on a side of the movable jaw. The distance between the jaws is set to be a value corresponding to the size of the workpiece when the pointer is aligned with one of the color marks.

Other objectives, advantages and features of the present invention will be apparent from the following description referring to the attached drawings.

The present invention will be described via detailed illustration of two embodiments referring to the drawings wherein:.

Referring to <FIG> and <FIG>, a torque-adjustable wrench <NUM> consists of a handle <NUM> and a bit <NUM> according to a first embodiment of the present invention. The bit <NUM> includes a body <NUM>, four color marks <NUM> through <NUM>, a worm, a movable jaw <NUM> and a pointer <NUM>.

The body <NUM> that is formed with adequate rigidity and hardness includes a front end <NUM> and a rear end <NUM>. An insert <NUM> extends from the rear end <NUM>. The insert <NUM> is formed with a hole <NUM> to receive a ball <NUM> and a spring <NUM> that is compressed between the ball <NUM> and a closed end of the hole <NUM>. The spring <NUM> presses a first portion of the ball <NUM> so that a second portion of the ball <NUM> sticks from the insert <NUM>. The hole <NUM> is made with a reduced open end to keep the first portion of the ball <NUM> in the hole <NUM>. The spring <NUM> is further compressed by the first portion of the ball <NUM> as the second portion of the ball <NUM> is located in the hole <NUM>.

A stationary jaw <NUM> extends from the front end <NUM>. The stationary jaw <NUM> and the front end <NUM> are made in one piece. The stationary jaw <NUM> is formed with a contact face <NUM>.

The front end <NUM> is formed with a groove <NUM>. The groove <NUM> consists of a cylindrical space <NUM> and a slot <NUM>, i.e., the cylindrical space <NUM> and the slot <NUM> are in communication with each other. The groove <NUM> extends perpendicular to a plane in which the contact face <NUM> lies. The cylindrical space <NUM> extends throughout the body <NUM>, i.e., the cylindrical space <NUM> includes two open ends. The slot <NUM> extends parallel to the cylindrical space <NUM>.

The movable jaw <NUM> that is formed with adequate rigidity and hardness includes a connective portion <NUM> extending from a rear end and a rack <NUM> extending along the connective portion <NUM>. Valleys <NUM> and teeth <NUM> are alternately arranged along a face of the rack <NUM>. The rack <NUM> is movable along the cylindrical space <NUM> while the connective portion <NUM> is movable along the slot <NUM> so that the movable jaw <NUM> is movable relative to the stationary jaw <NUM> along the front end <NUM>. The movable jaw <NUM> includes a contact face <NUM> pointed at the contact face <NUM> of the stationary jaw <NUM>. The rack <NUM> is formed with a diameter larger than the breadth of the slot <NUM> so that rack <NUM> cannot be moved from the cylindrical space <NUM> via the slot <NUM>. Thus, the movable jaw <NUM> is kept movable on the body <NUM>. Moreover, the movable jaw <NUM> is formed with two opposite sides <NUM> and <NUM> (<FIG>).

Referring to <FIG> and <FIG>, the body <NUM> includes two sides <NUM> and <NUM>. The body <NUM> includes a bore <NUM> and an opening <NUM>. The opening <NUM> includes an open end in the side <NUM> and another open end in the side <NUM>. The opening <NUM> is located between two sections of the bore <NUM>. The opening <NUM> is in communication with the cylindrical space <NUM>.

The worm includes an axle <NUM>, a cylinder <NUM> and a helical portion <NUM>. The cylinder <NUM> is inserted in the opening <NUM>. The axle <NUM> is inserted in the bore <NUM>. The axle <NUM> includes a section fitted in the cylinder <NUM> so that the axle <NUM> and the cylinder <NUM> are rotatable together. The helical portion <NUM> extends on the cylinder <NUM>. The helical portion <NUM> is engaged with some of the teeth <NUM> that are located in the opening <NUM>.

The color marks <NUM> to <NUM> are located on the side <NUM> of the body <NUM>. The color marks <NUM> to <NUM> are in different colors corresponding to various sizes of workpieces to be rotated by the torque-adjustable wrench <NUM>. The workpieces are nuts or threaded bolts for example.

The color mark <NUM> includes a colored layer 24A located in a recess 24B made in the side <NUM> of the body <NUM>. The color mark <NUM> includes a colored layer 25A inserted in a recess 25B made in the side <NUM> of the body <NUM>. The color mark <NUM> includes a colored layer 26A located in a recess 26B made in the side <NUM> of the body <NUM>. The color mark <NUM> includes a colored layer 27A inserted in a recess 27B made in the side <NUM> of the body <NUM>. The colored layers 24A, 25A, 26A and 27A are in different colors. Each of the recesses 24B, 25B, 26B and 27B includes a first portion in the form of a narrow groove and a second portion in the form of a circular bore. Thus, each of the color marks <NUM> to <NUM> includes a first portion in the form of a line corresponding to the narrow groove and a second portion in the form of a circle corresponding to the circular bore.

The color marks <NUM> to <NUM> are given as an example. There can be any other proper number color marks, or the color marks <NUM> to <NUM> can be in any other proper shape.

The pointer <NUM> is located on the side <NUM> of the movable jaw <NUM> corresponding to the color marks <NUM> through <NUM>. The pointer <NUM> includes a colored layer <NUM> located in a recess <NUM> made in the side <NUM> of the movable jaw <NUM>. The recess <NUM> is in the form of an equilateral or isosceles triangle, with a corner pointed at the front end <NUM> of the bit <NUM>. However, the pointer <NUM> can be in any other proper shape.

The pointer <NUM> is aligned with one of the color marks <NUM> to <NUM> so that the distance between the contact faces <NUM> and <NUM> is set at a value corresponding to one of the sizes of the workpieces. Thus, the adjustment of the value of the distance between the contact faces <NUM> and <NUM> is easy, without having to memorize, calculate or experience a trial-and-error process.

As follows, a table is given to illustrate a relationship between the color marks, the sizes of the workpieces (mm) and proper values of torque (Nm) to be exerted on the workpieces.

In use, the helical portion <NUM> is rotated to translate the rack <NUM> due to the engagement of some of the teeth <NUM> with the helical portion <NUM>. The movable jaw <NUM> is translated because the movable jaw <NUM>, the connective portion <NUM> and the rack <NUM> are made in one piece. Thus, the distance of the movable jaw <NUM> from the stationary jaw <NUM> is adjusted.

Referring to <FIG>, the distance between the contact faces <NUM> and <NUM> is D1 when the pointer <NUM> is aligned with the color mark <NUM>. D1 is <NUM> for example.

Referring to <FIG>, the distance between the contact faces <NUM> and <NUM> is D2 when the pointer <NUM> is aligned with the color mark <NUM>. D2 is <NUM> for example.

Referring to <FIG>, the distance between the contact faces <NUM> and <NUM> is D3 when the pointer <NUM> is aligned with the color mark <NUM>. D3 is <NUM> for example.

Referring to <FIG>, the distance between the contact faces <NUM> and <NUM> is D4 when the pointer <NUM> is aligned with the color mark <NUM>. D4 is <NUM> for example.

Referring to <FIG> and <FIG>, the handle <NUM> includes a shank <NUM>, a joint <NUM> formed at a front end of the shank <NUM>, and a grip <NUM> formed at a rear end of the shank <NUM>. A collar <NUM> is located on the shank <NUM>.

The insert <NUM> is inserted in the joint <NUM>. The rear end <NUM> of the bit <NUM> avoids excessive insertion of the insert <NUM> in the joint <NUM>. The ball <NUM>, which is located on the insert <NUM>, abuts against a first portion of the button <NUM> inserted in the joint <NUM> so that a second portion of the button <NUM> extends from the joint <NUM>. The button <NUM> can be pushed by the second portion so that the ball <NUM> is completely inserted in the insert <NUM> by the first portion of the button <NUM>. Thus, the insert <NUM> can be disengaged from the joint <NUM>.

A torque-indicating unit <NUM> includes a frame <NUM>, four colored regions <NUM>, <NUM>, <NUM> and <NUM>, and a lens <NUM>. The frame <NUM> is formed on the collar <NUM>. The colored regions <NUM>, <NUM>, <NUM> and <NUM> are located in the frame <NUM>. The colored regions <NUM>, <NUM>, <NUM> and <NUM> are given corresponding to the color marks <NUM>, <NUM>, <NUM> and <NUM>. The colored region <NUM> carries a number 575A that represents a first value of torque. The colored region <NUM> carries a first number 576A that represents a second value of torque. The four colored region <NUM> carries a number 577A that represents a third value of torque. The colored region <NUM> carries a number 578A that represents a fourth value of torque. The lens <NUM> is supported on the frame <NUM> so that the lens <NUM> extends over the colored regions <NUM>, <NUM>, <NUM> and <NUM>. The frame <NUM> is formed with a pointed portion <NUM>. A unit of torque <NUM> is printed on the frame <NUM>, near the pointed portion <NUM>. The unit of torque <NUM> is "Nm" for example.

The handle <NUM> is equipped with a torque-adjusting mechanism operable to adjust a maximum value of torque to be exerted on a workpiece via the torque-adjustable wrench <NUM>. The torque-adjusting mechanism includes a scale unit <NUM> including a lens <NUM> and a scale ring <NUM>. The scale ring <NUM> is rotated relative to the pointed portion <NUM> when the torque-adjusting mechanism is operated. Thus, the pointed portion <NUM> is pointed at a value of torque shown on the scale ring <NUM>. The lens <NUM> protectively covers the scale ring <NUM>.

Referring to <FIG>, for example, the torque-adjustable wrench <NUM> and an open-ended wrench <NUM> are used on an air conditioner <NUM>. In specific, the wrenches <NUM> and <NUM> are used together to connect a pipe <NUM> of the air conditioner <NUM> to another pipe <NUM>. To this end, a joint <NUM> is rotationally supported on the pipe <NUM>, and the pipe <NUM> includes a threaded section <NUM> and a nut <NUM>.

The open-ended wrench <NUM> includes a handle <NUM>, a head <NUM> formed at an end of the handle <NUM>, and two stationary jaws <NUM> extending from the head <NUM>. Each of the stationary jaws <NUM> includes a contact face <NUM> so that the contact faces <NUM> are pointed at each other. The distance between the contact faces <NUM> is constant.

The joint <NUM> includes six facets <NUM>. At least one of the facets <NUM> is provided with a colored layer <NUM>. The colored layer <NUM> is identical or similar to the colored layer 24A, 25A, 26A or 27A. According to the color of the colored layer <NUM>, the helical portion <NUM> is rotated to translate the movable jaw <NUM> to align the pointer <NUM> with the colored layer 24A, 25A, 26A or 27A of which the color is identical or similar to the color of the colored layer <NUM>. Thus, the distance between the contact faces <NUM> and <NUM> is easily set at D1, D2, D3 or D4 corresponding to the size of the joint <NUM>. Thus, the torque-adjustable wrench <NUM> can be used to rotate the joint <NUM>.

Moreover, the colored layer <NUM> is identical or similar to the colored region <NUM>, <NUM>, <NUM> or <NUM>. According to the number 575A, 576A, 577A or 578A, the torque-adjusting mechanism is used to set the maximum value of torque that can be transferred through the handle <NUM>. To this end, the scale ring <NUM> is rotated about the shank <NUM> to align a desired value with the pointed portion <NUM> of the frame <NUM>.

The jaws <NUM> of the open-ended wrench <NUM> are engaged with only the nut <NUM> made in a size. The jaws <NUM> and <NUM> of the torque-adjustable wrench <NUM> are engaged with the joint <NUM>. Then, the torque-adjustable wrench <NUM> is used to rotate the joint <NUM> on the threaded section <NUM> of the pipe <NUM> while the open-ended wrench <NUM> is used to keep the pipe <NUM> in position.

As described above, the torque-adjustable wrench <NUM> exhibits several advantages as follows:.

Firstly, the bit <NUM> is detachable from the handle <NUM> to allow another bit to be used with the handle <NUM>. Thus, the torque-adjustable wrench <NUM> can be used to rotate a wide range of workpieces.

Secondly, there is no need to memorize or calculate the relation of the size of a workpiece to the distance between the contact face <NUM> and <NUM> since the colored layer <NUM> is identical or similar to the color of the colored layer 24A, 25A, 26A or 27A. All it takes is to align the color mark <NUM>, <NUM>, <NUM> or <NUM> to the pointer <NUM>, and the distance between the contact faces <NUM> and <NUM> is substantially identical to the size of the workpiece.

Thirdly, there is no need to memorize or calculate a proper value of torque to be exerted on a workpiece corresponding to the size of the workpiece because the color mark <NUM>, <NUM>, <NUM> or <NUM> clearly points out that proper value of torque. All it takes is to read the value on the color mark <NUM>, <NUM>, <NUM> or <NUM> and accordingly use the torque-adjusting mechanism to set the proper value of torque.

Referring to <FIG>, there is shown a bit <NUM>' according to a second embodiment of the present invention. The bit <NUM>' is like the bit <NUM> except for two things. Firstly, additional color marks <NUM>, <NUM>, <NUM> and <NUM> are provided on the side <NUM> of the bit <NUM>'. That is, the bit <NUM>' includes two groups of color marks <NUM>, <NUM>, <NUM> and <NUM>. Secondly, an additional pointer <NUM> is provided on the side <NUM> of the movable jaw <NUM> of the bit <NUM>'. That is, the bit <NUM>' includes two pointers <NUM>.

Claim 1:
A torque-adjustable wrench (<NUM>), comprising:
a handle (<NUM>); and
a bit (<NUM>, <NUM>') attached to the handle (<NUM>), the bit (<NUM>, <NUM>') including a worm and
further comprising:
a body (<NUM>) comprising a front end (<NUM>) and a stationary jaw (<NUM>) extending from the front end (<NUM>);
a movable jaw (<NUM>) movably connected to the front end (<NUM>) of the body (<NUM>) so that a distance between the jaws (<NUM>, <NUM>) is adjustable; and
a pointer (<NUM>) formed on a side (<NUM>) of the movable jaw (<NUM>),
characterized in that
the handle (<NUM>) is equipped with a torque-adjusting mechanism operable to adjust a maximum value of torque to be exerted on a workpiece;
multiple color marks (<NUM>, <NUM>, <NUM>, <NUM>) are formed on a side of the body (<NUM>), wherein each of the color marks (<NUM>, <NUM>, <NUM>, <NUM>) is in a different color and corresponds to one of various sizes of a workpiece, wherein the distance between the jaws (<NUM>, <NUM>) is set to be a value corresponding to the size of the workpiece when the pointer (<NUM>) is aligned with one of the color marks (<NUM>, <NUM>, <NUM>, <NUM>); wherein each color mark (<NUM>, <NUM>, <NUM>, <NUM>) further corresponds to a colored region (<NUM>, <NUM>, <NUM>, <NUM>) of a torque-indicating unit (<NUM>) on the handle (<NUM>), each colored region (<NUM>, <NUM>, <NUM>, <NUM>) carrying a number (575A, 576A, 577A, 578A) that represents a corresponding maximum value of torque.