WO2014089883A1

WO2014089883A1 - Torque wrench

Info

Publication number: WO2014089883A1
Application number: PCT/CN2012/087492
Authority: WO
Inventors: 宝合.史蒂夫
Original assignee: 宝合扭力工具（上海）有限公司
Priority date: 2012-12-14
Filing date: 2012-12-26
Publication date: 2014-06-19
Also published as: CN103448010B; CN103448010A

Abstract

A torque wrench comprises a wrench head (1) and a wrench body (2). The wrench head (1) is arranged at the upper end of the wrench body (2). An elastic component (3), a release mechanism (4), and a torque resistance lever (5) are sequentially arranged in the wrench body (2) along the axial direction of the wrench body (2) from bottom to top. The elastic component (3) is connected with the release mechanism (4), the release mechanism (4) is connected with the torque resistance lever (5), the front end of the torque resistance lever (5) is connected with the wrench head (1), and the torque resistance lever (5) is connected with the upper end of the wrench body (1). By the aid of a large-diameter bearing wheel without a support and a rolling surface, an unnecessary side load on a force spring, due to the eccentric compression of an existing bearing wheel, can be reduced, and an extension stroke for an impulsive signal can be provided under the condition that the yield strength of a compression spring is not being surpassed.

Description

Description of the book

Technical field

The invention relates to the field of wrench manufacturing, in particular to a torque wrench. Background technique

Two standard types of manual torque wrenches are specified by the International Standard IS06789 International Organization for Standardization. Type 2 torque wrench is one of the standards. This type of wrench presets a predetermined torque value before use and provides various types of signals when the preset value is reached.

The present invention is applied to IS06789, ASME B107.14 of the United States, and Type 2 grade torque tools described by similar standards in other countries. The signal method of Type 2 wrench varies between grade and manufacturer, but the most common method is to provide a The instantaneous release of torque resistance, sometimes referred to as impulse, is often accompanied by clicks or clicks, especially in the widest range of wrench operations. In fact, this method is very common. Most types of setting wrenches are called “click wrenches”, even if the “click” is not necessarily the primary signaling mechanism. Other types of signal wrenches use other methods to signal, such as a click or click, a motor vibration or an audible click from a spring disk. The main disadvantage of most signal wrenches is that they often do not hear audible signals in the noisy environment of frequent industrial or car repairs. It was found that "rush" or "release" is the best display for determining the type 2 torque tool to achieve the proper torque. Therefore, if the setting tool and the above-mentioned human perception of the signal are widely used, the improvement in the release function can obviously make the tool better used and the result of ending the use can easily meet the demand and be trusted.

Type 2 Setting the calibration durability of the torque wrench is another area to consider. Use in many designs can easily lead to deterioration in accuracy. Wear or variation of components resulting from friction in the release mechanism used to prevent torque loading and release at predetermined torque values are two of the most common factors affecting accuracy.

In order to provide the most reliable and accurate torque calibration and signal, the set wrench must minimize friction in the release mechanism during the product's constant resistance to service life.

There are two ways to rub as little as possible. Since the release mechanism is often used when it is released, It must be moved along the axial direction of the wrench body, so that the area where the friction is mainly reduced is a linear stroke. The first method is to use a coating, such as Teflon or other coating, on the release mechanism to significantly reduce the axial friction of the linear support surface of the sliding surface of the release mechanism. These coatings are worn away after repeated use and frictional changes to affect torque accuracy. Unfortunately, this change is evident before the torque wrench reaches the end of its useful life.

The second method is to provide a linear rolling bearing to reduce the axial friction between the release mechanism and the wrench body. The existing linear bearing technology for torque wrench design mainly includes two types.

One type is to use a plurality of ball bearings in a cage, and when the start is completed, the accessory spring resets the ball bearings. This ball bearing design must use a small enough bearing to form a mechanism design. Since it is not possible to fit the configuration perfectly, the contact inside the wrench is limited to the ball provided at each end of the combination, and the line bearing system is easily inclined at an angle with respect to the direction of the stroke. Thus, an infinite pressure is created in the bearing contact area until sufficient deformation is produced to create a sufficient contact area to withstand the applied load. This deformation changes the initial alignment of the torque wrench and the rolling resistance of the wire bearing system. Therefore, it is necessary to design a large load supporting contact surface for blocking deformation.

The second type uses a load roller bearing to provide more load contact areas to prevent deformation. A complex support body is used in the prior art and a rolling surface of a wheel is provided by additional technical features for maintaining the position and positioning of the roller. This complex support body and additional roller surfaces add unnecessary production costs and limit the size of the rollers and surface contact areas for load support. It also adds errors due to the intentional or unintentional integration of manufacturing tolerances and leverage into the design. The intentional integration of the leverage factor to reduce the spring force can cause multiple reactions due to minor dimensional changes due to normal wear or other changes. Except for the axis of the roller located at the center position along the elastic axis position as the rotation axis of the connecting link, any installation will generate additional friction due to the eccentric compression of the roller with respect to the elastic shaft and generate a resilient side to the inner wall of the wrench body. Pressure.

Another factor that affects accuracy is the change in the compression spring that is used to provide the necessary torque resistance. Each compression stroke of the compression spring provides a defined amount of force. If the free length of the spring changes after the calibration process, the total amount of force generated will change and the accuracy of the torque will change. The most common reason for the change in the free length of the compression spring is that the spring becomes shorter due to excessive compression. This excessive compression causes the pressure to exceed the yield strength of the elastic material, and when the load is removed, the spring cannot be returned to its original length. Excessive compression can occur in some methods, including adjusting the wrench to a maximum setting that exceeds its design or because the improper design causes the spring to be compressed to More than its working limit. Torque wrenches have some practical limitations on physical dimensions for user manipulation, and designers tend to expand the design of compression springs to produce products that meet the requirements. If the wrench calibration does not exceed the maximum setting, the outer diameter of the spring, the density of the spring material, the strength of the spring material, the length of the spring, the total number of spirals, and the spring operating pressure are decisive factors for the spring performance.

As described above, the generation of the wrench signal requires a long release stroke but the linear bearing signal release mechanism moves in a linear direction along the axial direction of the wrench. This mechanism creates an amount that must be generated along the spring that exceeds this setting. This extra pressure increases the pressure of the unwanted spring material. The prior art uses an additional lever mechanism in the wrench body to supplement this longer release formation but necessarily creates unwanted appendages in the wrench body and can create undesirable additional costs. Summary of the invention

In view of the above existing problems, a torque wrench is now provided. The object of the present invention is to use a large diameter bearing wheel without a supporting body and a rolling surface for reducing unnecessary eccentric compression of the bearing wheel. The side load of the force spring and the extension stroke that provides a momentum signal without exceeding the yield strength of the compression spring.

The specific technical solutions are as follows:

A torque wrench includes a wrench member and a wrench body, wherein the wrench member is disposed at an upper end of the wrench body, wherein an axial direction of the wrench body in the wrench body is from below An elastic member, a release mechanism and a torque resistance lever are sequentially disposed, the elastic member being coupled to the release mechanism, the release mechanism being coupled to the torque resistance lever, a front end of the torque resistance lever and the wrench member The torque resistance lever is coupled to the upper end of the wrench body.

The above-described torque wrench, wherein the release mechanism includes a guide plate, a cam follower and a bearing wheel, the guide plate is disposed at an upper end of the elastic member, and the cam follower is disposed at the guide plate and the bearing wheel The bearing wheel is coupled to the torque resistance lever by a pivotal connection member.

In the above torque wrench, the bearing wheel is adapted to an inner diameter of the wrench body, and an outer surface of the bearing wheel and an inner wall of the wrench body are in contact with each other.

The above-mentioned torque wrench, wherein the bottom end of the torque resistance lever includes a first inclined surface structure, the top end of the first inclined surface structure is a protruding structure, and a notch is included on an outer diameter of the bearing wheel, the concave Port and the protruding structure Suitably, the torque resistance lever is coupled to the recess by the pivotal connection member.

In the above torque wrench, wherein one side of the bearing wheel with respect to the recess is a second inclined surface structure, and the second inclined surface structure is adapted to the first inclined surface structure.

The above-mentioned torque wrench, wherein a portion of the bearing wheel connected to the cam follower is provided with a reset cam surface, and the reset cam surface is a groove or a planar structure.

In the above torque wrench, wherein the cam follower is spherical, the cam is mounted in the guide plate in an axially aligned manner with the guide plate, and the cam follower rolls on the guide plate.

The above-mentioned torque wrench, wherein the pivotal connecting member has one or more plates forming a pivoting structure, one end of the pivotal connecting member is located on a center line of the bearing wheel, and the other of the pivotal connecting members One end is mounted at the bottom end of the torque resistance link.

In the above torque wrench, the torque resistance lever is coupled to the upper end of the wrench body by a cylindrical pin. The above-mentioned torque wrench, wherein the torque resistance lever is provided with a calibration screw near one end of the bearing wheel. The beneficial effects of the above technical solutions are:

1. The signal release stroke can be provided by the wrench body, linear bearing, torque resistance lever and connection design by 43% to 120% larger than the prior art.

2. The long release stroke and rapid acceleration of the lever produce a more perceptible signal to indicate that a predetermined torque value has been reached.

3. Achieve low friction rolling and linear bearing while saving cost and provide a large rolling contact surface.

4. The large rolling contact surface prevents dents in the wrench body from changing the direction of the force member and thereby changing the torque accuracy.

5. The large rolling contact surface creates less resistance to rolling and lower friction, thereby providing more continuous torque accuracy over multiple starts.

6. No additional accessory springs or continuous tracks of the ball used in other rolling linear bearing systems are required, by which the bearing wheel is repositioned and the linear bearing action automatically resets for the next start.

7. A simple integral cam follower is aligned with the force vector axis and does not adversely affect the movement of the bearing wheel. Force.

8. The cam follower mates with the rounded surface of the linear force guide to ensure shaft alignment and rolling to avoid drag effects on the rolling motion.

9. The notched portion of the bearing wheel includes a sufficiently short joint design that produces a quick release action that readily senses the release signal, extends the torque resistance arm stroke, and shortens the stroke of the linear bearing action.

10. The torque resistance arm and the notched portion of the bearing wheel move the bearing wheel in the direction of rotation to achieve the rolling required to complete the linear movement.

11. The torque resistance arm and the notched portion of the bearing wheel move the bearing wheel in a rotational direction to achieve the rolling required to complete the linear movement.

12. The inclusion of a matching bearing surface in the wrench body and on the bearing wheel ensures accurate positioning of the bearing wheel within the wrench body without the need for an additional bearing body. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

1 is a schematic structural view of a torque wrench of the present invention.

2 is a side view of a torque wrench of the present invention.

3 is a schematic view showing the structure of a torque wrench of the present invention in a state in which a release signal is issued.

Fig. 4 is a schematic enlarged view showing the release mechanism shown in Fig. 2.

Fig. 5 is an enlarged schematic view showing the release mechanism shown in Fig. 3.

Figure 6 is a plan view of the wrench body in the present invention.

Figure 7 is a cross-sectional view of a bearing wheel in the present invention. detailed description

The invention is further described below in conjunction with the drawings and specific embodiments, but is not to be construed as limiting. As shown in FIG. 1 to FIG. 7 , a torque wrench includes a wrench member 1 and a wrench body 2 , wherein an elastic member 3 is sequentially disposed in the wrench body 2 along a linear axial direction of the wrench body 2 . The release mechanism 4 and the torque resistance lever 5 are connected to a release mechanism 4 (indicated by the frame in the drawing), and the release mechanism 4 is coupled to the wrench body 2 via a torque resistance lever 5.

In one embodiment of the invention, the release mechanism 4 includes a guide 40, a cam follower 41 and a bearing wheel 42, wherein the guide 40 is disposed at the upper end of the resilient member 3, and the cam follower 41 is disposed on the guide 40 and the bearing Between the wheels 42; the bearing wheel 42 is connected to the torque resistance lever 5 via a pivotal connection member 43.

In practice, a force vector is applied to the bearing wheel 42 through the guide plate 40 and the cam follower 41 through the guide member 40 and the cam follower 41 in the linear axial direction of the wrench body 2 through the elastic member 3, and the torque resistance through the connection The lever 5 achieves the torque to control the torque wrench. When a torque is applied to the torque resistance lever 5 through the wrench member 1, a component force perpendicular to the force vector is generated by the pivotal connecting member 43 and a torque resistance is generated, which is pivoted by the torque resistance lever 5 When the connecting member 43 applies a force, when the component force perpendicular to the force vector is greater than the force vector, the pivotal connecting member 43 accelerates and acts on the torque resistance lever 5, and the movement of the torque resistance lever 5 makes the wrench body 2 The torque resistance suddenly decreases, producing a release signal. When the applied force reaches a certain ratio with the wrench, the torque resistance lever begins to tap the torque body 2 to produce an audible "click" sound.

In one embodiment of the present invention, the bearing wheel 42 is in contact with the inner wall of the wrench body 2, specifically, the bearing wheel 42 is sufficiently thick and the bearing wheel 42 has a bearing wheel surface, the surface of the bearing wheel 42 and the wrench body 2 The inner surface is in full contact, so that the bearing wheel 42 and the wrench body 2 can be prevented from being deformed while being subjected to high load and having low rolling resistance. In addition, the close cooperation of the wrench body 2 with the bearing wheel 42 ensures the correct positioning of the bearing wheel 42 in the wrench body 2.

In one embodiment of the present invention, the bottom end of the torque resistance lever 5 includes a first bevel structure 50, the top end of which is a protruding structure 51, and includes a notch 420 on the outer diameter of the bearing wheel 42, the notch 420 In conjunction with the protruding structure 51, which is confined in the recess 420, the torque resistance lever 5 is connected at the recess 420 by a pivotal connection member 43.

In one embodiment of the invention, as shown in FIG. 5, one side of the bearing wheel 42 relative to the recess 420 is a second beveled structure 44 that is adapted to the first beveled structure 50. When the applied torque reaches a certain value, the bearing wheel 42 can be moved to a maximum stroke, and the torque resistance lever 5 is adjusted to be unaffected by the bearing wheel 42. The limit of scrolling.

In implementation, the pivotal movement of the torque resistance lever 5 and the pivotal coupling member 43 causes the bearing wheel 42 to move along the axis of the torque wrench and away from the pivotal joint. The torque resistance lever 5 is restrained in the rolling stroke of the bearing wheel 42, the stroke limit being such that the torque resistance lever is automatically reset after the load is released.

In one embodiment of the invention, the portion of the bearing wheel 42 that is coupled to the cam follower 41 is provided with a reset cam surface 421 that is a recess through which the cam is cammed The follower 41 is positioned therein, by which the torque resistance lever 5 can be automatically reset without the need for an attached spring or other mechanism to assist in achieving the reset.

In one embodiment of the invention, the cam follower 41 is spherical, and each face on the centerline of the ball has an equal thickness, the cam follower 41 is mounted in the guide 40, and the cam is The movable member 41 has a matching with the guide 40, which is axially aligned with the guide 40, which is placed in the axial direction of the elastic member 3, and the cam follower 41 rolls in the guide 40.

In one embodiment of the invention, the pivotal connection member 43 has one or more plates forming a pivoting structure, one end of the pivotal connection member 41 being located on the centerline of the bearing wheel 42, the other end of the pivotal connection member 41 Installed at the bottom end of the torque resistance link 5.

In one embodiment of the invention, the torque resistance lever 5 is coupled to the wrench body 2 by a cylindrical pin 6. In one embodiment of the invention, the torque resistance lever 5 is provided with a calibration screw 7 near one end of the bearing wheel 2, and the torque resistance lever 5 is offset from the force vector generated by the elastic member 3 by a certain angle by the adjustment of the calibration screw 7.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the scope of the claims of the present invention. Therefore, equivalent structural changes made by using the specification and the description of the present invention are included in the scope of the present invention. .

Claims

Claim

A torque wrench comprising a wrench member and a wrench body, the wrench member being disposed at an upper end of the wrench body, wherein an axial direction of the wrench body is in the wrench body An elastic member, a release mechanism and a torque resistance lever are sequentially disposed from the lower side, the elastic member is coupled to the release mechanism, and the release mechanism is coupled to the torque resistance lever, and the front end of the torque resistance lever is A wrench member is coupled and the torque resistance lever is coupled to the upper end of the wrench body.

The torque wrench according to claim 1, wherein the release mechanism comprises a guide plate, a cam follower and a bearing wheel, the guide plate is disposed at an upper end of the elastic member, and the cam follower is disposed Between the guide plate and the bearing wheel; the bearing wheel is coupled to the torque resistance lever by a pivotal connection member.

The torque wrench according to claim 2, wherein the bearing wheel is adapted to an inner diameter of the wrench body, and an outer surface of the bearing wheel and an inner wall of the wrench body are in contact with each other.

The torque wrench according to claim 2, wherein the bottom end of the torque resistance lever comprises a first inclined surface structure, and the top end of the first inclined surface structure is a protruding structure outside the bearing wheel The notch includes a notch that is adapted to the protruding structure, and the torque resistance lever is coupled to the recess by the pivotal connection member.

The torque wrench according to claim 4, wherein one side of the bearing wheel with respect to the recess is a second inclined surface structure, and the second inclined surface structure is suitable for the first inclined surface structure Match.

The torque wrench according to claim 2, wherein a portion of the bearing wheel connected to the cam follower is provided with a reset cam surface, and the surface of the reset cam is a groove or a Plane structure.

The torque wrench according to claim 2, wherein the cam follower is spherical, and the cam is mounted in the guide plate in an axially aligned manner with the guide plate, the cam is The moving member rolls on the guide.

The torque wrench according to claim 2, wherein the pivotal connecting member has one or more plates forming a pivoting structure, and one end of the pivotal connecting member is located at a center line of the bearing wheel The other end of the pivotal connection member is mounted at a bottom end of the torque resistance link.

The torque wrench according to claim 1, wherein the torque resistance lever is coupled to an upper end of the wrench body by a cylindrical pin.

The torque wrench according to claim 2, wherein the torque resistance lever is provided with a calibration screw near one end of the bearing wheel.