JP2000042937A - Torque wrench - Google Patents

Abstract

PROBLEM TO BE SOLVED: To visually confirm fastening of a screw jointed with a preset torque at fastening work time by providing a visual display interlocking with a toggle link and having a display body projecting to the outside surface of a handle member, on the outside of a torque wrench handle member. SOLUTION: In performing fastening work of a fastening object screw by using a torque wrench main body having a visual display 2, when the fastening object screw reaches a prescribed fastening torque, a head member 4 rotates in the anticlockwise direction. Rotation of the head member 4 rotates a suppressing link 18 in the anticlockwise direction to release pressing force of the coil spring extension part 16A, so that a display body 17 projects outside a cover 20 from the opening part 21 together with the coil spring extension part 16A for springing up the coil spring extension part 16A. Fastening force of the fastening object screw can be confirmed to have reached a prescribed torque by visually observing this projecting situation to thereby prevent excessive torque fastening or a fastening accident of the fastening object screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque wrench used for fastening a screw or the like, and more particularly, to a display body projecting from the torque wrench when the fastening torque reaches a predetermined set value during a screw fastening operation. The present invention relates to a torque wrench provided so as to visually confirm completion of screw fastening.

[0002]

2. Description of the Related Art A general configuration of a conventional torque wrench used to fasten a screw to be fastened at a predetermined set torque value includes a head member of the torque wrench and a handle member which supports the head member. A toggle link mechanism is interposed therebetween, and when the fastening torque of the screw to be fastened reaches a predetermined fastening torque, the toggle link mechanism operates to generate an operation impact sound (click), and this operation impact sound is generated. The fastening operator knows that the fastening screw has been fastened at the set torque value of the torque wrench.

In a relatively quiet environment where the screw fastening work site using the torque wrench has little noise, the fastening worker can easily detect the operation impact sound of the toggle link mechanism. At work sites where the ambient noise is severe, such as when the work site is screwing railroad rails to piles, it is often difficult to check the operation impact sound of the toggle link mechanism. There has been a problem that excessive fastening torque force easily causes bolt breakage and loosening due to depression of the seat surface.

[0004] Therefore, during the fastening operation of the screw using the torque wrench, the present applicant has a switch interlocked with the operation of the toggle link mechanism built in the torque wrench and a display of the fastening information (alarm) activated by the function of the switch. Various applications have already been filed concerning a screw fastening confirmation system that includes means and can electrically and visually confirm the fastening status of a screw to be fastened.

[0005]

However, in such a screw fastening confirmation system and the like, a power supply is required because the mechanical operation of the toggle link mechanism must be converted into an electrical operation. Therefore, it is difficult to supply a power, particularly at an outdoor screw fastening site, and it has been impossible to use the screw fastening confirmation system using the power as described above.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and when a predetermined set torque value is reached during the fastening operation of a screw to be fastened using a torque wrench, the torque wrench of the torque wrench is interlocked with the operation of a toggle link mechanism. On the outside, a torque wrench is provided with a display body that is mechanically projected without using electric energy such as a commercial power supply and a battery,
When the fastening torque of the screw to be fastened by the torque wrench reaches the set torque value, the display body protrudes by a mechanical operation, and with the protrusion of the display body, the fastening operator fastens the fastening force of the screw at the set torque value. The purpose is to develop a torque wrench that allows the user to visually confirm the fact.

[0007]

In order to achieve the above object, according to a first aspect of the present invention, there is provided a head member rotatably supported on a handle member of a torque wrench via a head pin. In a torque wrench having a toggle link mechanism interposed between a tail end of a head member and a thruster supported so as to be axially displaceable inside the handle member, a visual indication is provided outside the torque wrench handle member. A visual indicator which stands up (projects) on the outer surface of the handle member by using the restoring force of a spring.
And a restraining link that restrains the restoring force of the spring to restrain the display body from rising. The head member is engaged with the restraining link so that when the screw to be fastened is fastened. And a torque wrench provided with an operating pin for moving the restraining link in the spring restraining force restraining direction or the non-restraining direction by the operation of the head member.

[0008] According to a second aspect of the present invention, in addition to the first aspect, the display is a torque wrench formed of a light-emitting body such as a light collector or a light storage.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings.

In this embodiment, as shown in FIG. 1, a torque wrench having a visual indicator 2 attached to a torque wrench main body 1 is constituted by a well-known preset type torque wrench. Since it does not substantially change, its outline will be described. Reference numeral 3 denotes a cylindrical handle member.
A head member 4, a part of which is housed inside the handle member 3, is pivotally supported by a head pin 5 at the front end of the handle member 3. Further, a thruster 6 is accommodated inside the handle member 3 so as to be movable in the axial direction of the handle member 3.

The thruster 6 and the head member 4 are connected by a toggle link 7, and the thruster 6 is connected to a spring 8 provided inside the handle member 3.
Is pressed in the direction of the head member 4. Reference numeral 9 denotes an adjusting screw for adjusting a compressive load for pressing the spring 8 in the direction of the thruster 6, and reference numeral 10 denotes an operating pin implanted and supported by the head member 4.

The above is the configuration of the torque wrench main body.
Next, the structure of the visual indicator mounted and maintained on the handle member 3 of the torque wrench body 1 will be described.

Reference numeral 11 denotes a substrate of the visual indicator 2. On the upper surface of the substrate 11, a column 12 which stands upright with respect to the upper surface is fixed, and has a substantially U-shaped side surface. The spring receiving frame 13 is fixed by mounting screws 14. The spring support frame 13 has the support 1
A support shaft 15 having a horizontal shaft center in a direction orthogonal to the second shaft center direction is mounted, and a coil spring 16 is wound and supported on the support shaft 15.

One end of the coil spring 16 has a three-dimensional display 17 mounted on the tip of an extension 16A extending away from the support shaft 15, and the other end 16B of the coil spring 16 has a spring receiver. It is locked to the frame 13.
Reference numeral 18 denotes a restraining link formed in a substantially L-shape in a plane. The center of the restraining link is rotatably supported by a support 12 standing on a substrate 11. Is formed in a U-shaped notch 19 in which the upper end of the operating pin 10 is locked.

The other end 18B of the restraining link 18 is formed as a spring holding portion for pushing down the extension 16A of the coil spring 16 against its elastic force.

Reference numeral 20 denotes a cover of the visual indicator 2. The cover 20 has an extension 16A of the coil spring 16 provided thereon.
In addition, an opening 21 for allowing the display 17 to protrude and retract from the outside and inside of the cover 20 is formed.

The operation of the present embodiment has been described above. Next, the operation will be described. The tightening operation of the screw to be fastened is performed by using the torque wrench main body 1 provided with the visual display 2. When a predetermined tightening torque value is reached, the toggle link 7 operates, and the head member 4 rotates about the head pin 5 in the handle member 3 in the counterclockwise direction in FIG. The rotation of the head member 4 is transmitted to the restraining link 18 in the visual indicator 2 via the operating pin 10, and the restraining link 18 rotates counterclockwise about the support 12 in FIG.

By turning the restraining link 18 counterclockwise in this manner (see FIG. 5), the pressing force of the coil spring extension 16A by the other end 18B of the restraining link 18 is released. The coil spring extension 16
A is the elastic restoring force of itself, and jumps up as shown in FIG. 6, so that the display body 17 attached to the tip of the coil spring extension 16A and the cover 2 together with the coil spring extension 16A.
The cover 20 protrudes from the opening 21 provided outside the cover 20 to the outside. Therefore, the screw fastening operator can visually confirm that the fastening force of the screw to be fastened by the torque wrench main body 1 has reached a predetermined torque value by visually observing the projecting state of the display body 17 to the outside of the cover.

As described above, the torque wrench of the present embodiment is provided with the visual indicator whose display is mechanically projected outside the torque wrench main body 1 in association with the operation of the toggle link. Even if the operation sound or the impact sound of the toggle link mechanism in the torque wrench is lost during the screw fastening operation, the screw to be fastened is already fastened with the predetermined fastening torque value by the projecting action of the display body 17. Can be easily and reliably visually confirmed.

If the display 17 is formed of a light collector or a light accumulator that collects external light, the projecting state of the display can be easily checked even at the work site of screw fastening in a dark place such as at night. can do.

[0021]

As described above, according to the torque wrench of the present invention, it is difficult to confirm the operation sound of the toggle link, the impact sound, and the like, even in the case of a screw tightening work site where noise is intense.
By visually observing the state of protrusion of the display body, it is possible to visually confirm whether or not the screw has been tightened at a predetermined set torque value. It is possible to prevent a fastening accident (miss) from occurring.

According to the torque wrench of the present invention,
Since the display operation by the display is performed by a mechanical operation related to the operation of the toggle link, there is no need to use a power supply such as a commercial power supply or a battery, and therefore, a work site where power supply is difficult or impossible. Can be used effectively in Further, according to the torque wrench according to the second aspect of the present invention, even at the work site in a dark place such as at night, it is possible to reliably visually confirm the completion of the fastening of the screw to be fastened by the projecting operation of the display body. .

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view showing an embodiment of a torque wrench according to the present invention.

FIG. 2 is a partially cutaway plan view showing a toggle link operation of the torque wrench.

FIG. 3 is a plan view of a visual display according to the present invention.

FIG. 4 is a side view of the visual display of the present invention.

FIG. 5 is an operation explanatory plan view of the visual display device according to the present invention.

FIG. 6 is a side view for explaining the operation of the visual display of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Torque wrench main body 2 ... Visual display 3 ... Handle member 4 ... Head member 5 ... Head pin 6 ... Thruster 7 ... Toggle link 8 ... Spring 9 ... Adjustment screw 10 ... Operating pin 11 ... Substrate 12 ... Strut 13 ... Spring receiving frame DESCRIPTION OF SYMBOLS 14 ... Mounting screw 15 ... Support shaft 16 ... Coil spring 17 ... Display body 18 ... Suppression link 19 ... Notch 20 ... Cover 21 ... Opening

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[Procedure amendment]

[Submission date] May 24, 1999 (1999.5.2
4)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

In order to achieve the above object, according to a first aspect of the present invention, there is provided a head member rotatably supported on a handle member of a torque wrench via a head pin. In a torque wrench having a toggle link mechanism interposed between a tail end of a head member and a thruster supported so as to be axially displaceable inside the handle member, a visual indication is provided outside the torque wrench handle member. Wherein the visual indicator is a torque wrench.
Of the display body which is erected (protrude) with respect to the outer surface of the handle member by utilizing the resiliency of the interlocking vital spring operation of the toggle link, the standing of deterrence to display body a restoring force of the spring The head member has a toggle link mechanism at the time of fastening the screw to be fastened .
An operation pin for rotating the inhibiting link in relation to the operation of the head member accompanying the operation , the toggle link machine
The restoring force of the spring is released
It is a torque wrench that raises the display body outside the handle member of the torque wrench.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

[0021]

As described above, according to the torque wrench of the present invention, the screw tightening torque is set to the set torque value of the torque wrench.
The display body stands outside the handle member of the torque wrench
To be operated, the screw tightener must
Is the position of the display object extremely easy while performing
It can be surely confirmed visually. Therefore, even in the case of a screw tightening work site or the like where the operation sound of the toggle link or the impact sound is difficult to confirm, the screw is tightened at a predetermined set torque value by visually observing the state of protrusion of the display body. It is possible to know the situation of whether or not it is extremely easy and surely, whereby it is possible to prevent a fastening accident (miss) due to excessive torque fastening of the fastened screw or insufficient fastening torque.

Claims (2)

[Claims] A head member rotatably supported by a handle member of a torque wrench via a head pin, and a tail end of the head member and an axially displaceable support inside the handle member. A torque wrench having a toggle link mechanism interposed between the thruster and a thruster, wherein a visual indicator is provided outside the torque wrench handle member, and the visual indicator reduces a restoring force of a spring. The display device has a display body that stands up (projects) with respect to the outer surface of the handle member, and has a restraining link that suppresses the restoring force of the spring to prevent the display body from standing up. An operating pin for engaging with the restraining link and moving the restraining link in the restoring force suppressing direction of the spring or in the non-inhibiting direction by the operation of the head member at the time of fastening the fastened screw. A torque wrench characterized by being provided. 2. The torque wrench according to claim 1, wherein the display body is formed of a light emitting body including a light collecting body, a light storage body, and the like.