TWI614094B - Automatic screwdriver that can adjust dynamic load accuracy - Google Patents

Description

Automatic screwdriver that can adjust dynamic load accuracy

The present invention relates to the art of a planar bearing for an automatic screwdriver construction, and more particularly to an automatic driver that can adjust the dynamic load accuracy.

According to the error of the automatic actuator (including electric and pneumatic type), it is generally generated by the sum of the maximum tensile stress and the maximum friction minus the minimum tensile stress, and then after the rotation, it is called Torque error value, commonly known as torque accuracy.

Generally, the electric screwdriver can only select the torque error value in the torque of large, medium and small torque. Generally, the maximum torque is selected as the standard of the error value, but the accuracy error of the medium and low torque will be large, especially when the torque is low. The error is the biggest.

However, the average operator uses medium or low torque as the standard of use of the tool, and rarely uses the maximum torque as the maximum error value, because the maximum torque will reduce the life of the tool, so the design does not meet the actual use. Often the actual error value will be greater than the reference error value written in the catalog. Occasionally, the locking screw used on the aircraft, car or other items will be found to cause slipping or locking, which may lead to accidents.

The main object of the present invention is to provide an automatic screwdriver capable of adjusting the dynamic load accuracy. By dispersing more than one single or composite dynamic bearing installed in the automatic screwdriver, the internal structure such as the clutch can be controlled during the operation of the automatic screwdriver. Force can use the fulcrum fulcrum Displacement to eliminate the torque error caused by friction and provide the best torque accuracy under the range of full torque (ie different torque values).

Another object of the present invention is to provide an adjustable dynamic load accuracy By using a preloading force of a screw or a nut to generate a Tensile stress, the gear gap can be minimized, the Tension loss is reduced, and the overall stiffness is enhanced. In addition, the strength of the elbow gear can be increased, and the large torque can be achieved in a small space, so that the size of the elbow becomes small, and when the small space is locked, the locking screw can be locked, which is not achieved by the automatic screwdriver of the general elbow.

In order to achieve the above objectives, the technical solution adopted in this case is distributed within the automatic screwdriver. Providing at least one set of dynamic bearings, the dynamic bearing comprising: at least one layer of flat warrior of unlimited thickness, and at least two or more unrestricted number of surrounding steel balls of high and low differential fulcrum; the dynamic bearing It is a kind of bearing with composite design. It is more than one plane bearing. The force of each load (such as total load tension and total load pressure) is calculated by force. The deformation amount δ of the material is used, and the deformation amount of the material is utilized. To calculate the load force of the large, medium and small full torque range (such as total load tension, total load pressure), so that when there is small torque, there is a small torque friction error value, medium torque, medium torque torque error value, high torque The value of the frictional error with high torque can be made more accurate by eliminating the torque error value of all torques.

The high and low differential fulcrum structures in the above dynamic bearings can be sized differently. The steel ball is reached.

The high and low difference fulcrum structure in the above dynamic bearing can be adopted in the plane Huashi relative The contact faces of the steel balls are set to have different depths of curvature and the track is achieved.

The high and low difference fulcrum structure in the above dynamic bearing can be adopted in the plane Huashi relative The contact faces of the steel balls are set to track with different radius of rotation.

The high and low fulcrum fulcrum structure in the above dynamic bearing can be obtained by using a track with different rotation radii on the contact surface of the plane slab relative to the steel ball, and setting steel balls with different diameters.

The high and low differential fulcrum structure in the above dynamic bearing can be achieved by providing a support ring smaller than the diameter of the steel ball around the inner edge of the steel ball.

The difference bearing fulcrum of the above dynamic bearing can be achieved by providing a support seat rotating ring around the outer edge of the steel ball.

The preset deformation amount of the above dynamic bearing includes a radial deformation amount and an axial deformation amount.

The dynamic bearing includes a pre-locking structure for resisting axial deformation, and the shaft of the dynamic bearing is coupled with two bearings by a screw or nut screw.

The invention changes the fixed friction force into a variable friction force, and uses different friction coefficients to fight against different torque states, thereby making the automatic screwdriver tool torque precision more precise, and the advantages are as follows: 1. Torque error value When it becomes smaller, the torque error value CMK increases by about one to two units before the decimal point, and the larger the value, the better. 2. The influence of temperature on the automatic screwdriver becomes smaller. Because the friction is reduced, the influence of temperature and force on the automatic screwdriver becomes smaller, and the use of the automatic screwdriver with high speed and high cycle can not cause too high error. value. 3, the lubrication effect is better, the relative life of the automatic screwdriver is longer. 4. For the automatic screwdriver when the hard torque and the soft torque are locked, the error value will become smaller. 5. Due to the reduced friction, the automatic screwdriver can operate in low temperature or high temperature working environment.

a, c, e‧‧‧ plane Huasi

b, d, f‧‧ fulcrum

F1~f6‧‧‧ steel ball

A~H‧‧‧ dynamic bearing

1‧‧‧Clutch

2‧‧‧Connected shaft

3‧‧‧screws (or nuts)

4‧‧‧Support ring adjustment rotation ring

5‧‧‧Support seat adjustment rotating ring

6‧‧‧ bearing fixed support

The first figure is a linear diagram of the principle of frictional force applied in the application of the invention; the second figure (a) is a schematic diagram of the bearing force (small torque) of the application of the invention; the second figure (b) is a schematic diagram of the force of a general planar bearing ( The second figure (c) is a schematic diagram of the dynamic bearing according to the principle of the second figure (a) of the present invention; and the third figure (a) is a schematic diagram of the bearing force (middle torque) of the application of the present invention; Figure 3 (b) is a schematic diagram of the force of a general planar bearing (2); the third diagram (c) is a schematic diagram of the dynamic bearing according to the principle of the third diagram (a) of the present invention (2); the fourth diagram (a) is the invention Schematic diagram of the applied bearing force (high torque); the fourth figure (b) is the general plane bearing force diagram (3); the fourth figure (c) is the dynamic bearing diagram of the invention according to the fourth figure (a) principle (3) The fifth figure is a schematic diagram of the partial structure of the dynamic bearing according to the fourth figure (a) of the present invention; the sixth figure is a schematic diagram of the difference between the use of the steel ball of the dynamic bearing and the general planar bearing of the present invention; Schematic diagram of the steel ball arrangement of the dynamic bearing of the invention (1); seventh diagram (b) is a schematic diagram of the steel ball arrangement of the dynamic bearing of the present invention (2); seventh figure (c) The schematic diagram of the steel ball of the dynamic bearing of the present invention is provided (3); the eighth figure (a) is a schematic diagram of the principle of applying the Hertz contact in the present invention; and the eighth figure (b) is the force of the clutch according to the principle of the eighth figure (a). Schematic diagram (1); the ninth diagram is a schematic diagram of the invention applicable to the automatic vertical screwdriver structure; the tenth diagram is a schematic diagram of the invention applicable to another elbow type automatic screwdriver; the eleventh figure is the invention applied to the automatic screwdriver Schematic diagram of the internal force principle (2); the twelfth figure is a schematic diagram of the force principle of the invention applied to the automatic screwdriver (3); and the thirteenth figure (a) is a schematic diagram of the dynamic bearing structure deformation of the present invention (1) ; Figure 13 (b) is a schematic view showing the deformation of the dynamic bearing structure of the present invention (2); the thirteenth drawing (c) is a schematic diagram of the deformation of the dynamic bearing structure of the present invention (3); and the thirteenth drawing (d) is the present invention Schematic diagram of dynamic bearing structure deformation (4); Fig. 13 (e) is a schematic diagram of deformation of dynamic bearing structure of the present invention (5); and Fig. 13 (f) is a schematic diagram of deformation of dynamic bearing structure of the present invention (6); Figure 13 (g) is a schematic diagram of the deformation of the dynamic bearing structure of the present invention (7); Figure 14 is a schematic view showing the deformation of the dynamic bearing structure of the present invention (8); (9); The sixteenth figure is a schematic diagram of the deformation of the dynamic bearing structure of the present invention (10).

The invention provides an automatic screwdriver capable of adjusting a dynamic load, mainly comprising at least one set of dynamic bearings disposed in the automatic screwdriver.

First of all, regarding the principle of the design of the case, please refer to the first figure, in which the friction coefficient (μ min and μ max) will affect the accuracy of the torque. It is known from the drawing that the total error value is The frictional force is inseparable. To obtain accurate torque, it is necessary to reduce the frictional error. Therefore, it is very important to make the variable frictional force μ, which is also the focus of the present invention, because under different torques. There will be different tensile stresses, and the best friction coefficient will be obtained under the range of maximum clamping force Fv max and minimum clamping force Fv min (mainly from spring force and clutch size). Torque accuracy (ie, between the minimum tolerated limit torque T11 and the highest allowable limit torque Tul).

According to the foregoing theory, the dynamic bearing of the present invention is structurally designed as shown in the second figure (c), and includes: at least one layer of flat huasi a of unlimited thickness, and at least two The fulcrum b is formed by an unlimited number of surrounding steel balls, and the fulcrum b having the difference means that any one of the fulcrums has a predetermined deformation amount in height with respect to the other fulcrum.

Please refer to the second to fourth figures together, and the series will be based on the principle of force. The structural difference between the plain planar bearing and the dynamic bearing of the present invention; as shown in the second diagram (a), a basic force principle diagram of the static force F (small torque) of the bearing torsion spring is disclosed, wherein the foundation of the bearing The structure comprises: a flat washer a having a thickness t, and a point b, wherein δ represents a deformation amount, the F represents the force of the torsion spring, and Δ represents the fulcrum b and is distinguished by a fulcrum f1 and a fulcrum f2. When the plane washer a and the fulcrum b are subjected to the static force F (small torque) of the torsion spring, the static force F exerts a slight force on the plane washer a, and only produces a small amount of deformation (due to the torque) The spring has not been squeezed yet, so the force of the two points f1 is also small, and the plane washer a is only supported by the support point f1 without touching the support point f2.

As shown in the second figure (b), it is disclosed that it is commonly used in automatic screwdrivers. The plane bearing, the structure includes: a flat washer a and a point b; because the friction generated by the general use is relatively small, so the design does not need to use a lot of fulcrum b (ie steel ball), only the fulcrum one (ie, steel ball one) f1 is sufficient as a support, the total friction is relatively small (the total friction is small because the number of steel balls used is small), and it does not appear under the use of the static force F (small torque) of the torsion spring. The problem of torque accuracy without affecting the service life.

As shown in the second figure (c), the dynamics of a preferred embodiment of the present invention are disclosed. The bearing basic structure, wherein the design of the same principle as the second figure (a) is adopted, comprising: a plane washer a and a point b, and the fulcrum b further comprises a steel ball f1 and a steel ball f2 having a difference setting Structure; therefore, when the dynamic bearing is used in the automatic screwdriver, under the action of the static force F (small torque) of the torsion spring, high-precision torque and long service life can still be obtained; as for the plane Huasi a The upper steel ball (f1) can be set according to actual needs, and has the function of slowing the static force F of the torsion spring.

Secondly, as shown in the third figure (a), the movement of a bearing torsion spring is disclosed. Schematic diagram of the basic force principle of force F (medium torque); according to this design, when the plane washer a and the pivot b are subjected to the power F (middle torque), the system produces a moderate degree of deformation to the plane washer a, The force of the fulcrum one at the fulcrum b (f1) is also moderate, and the plane huasi a is in contact with the fulcrum two (f2) of the fulcrum b due to deformation.

As shown in the third figure (b), a general planar bearing structure is disclosed, including There is a flat washer a and a point b; when the bearing is subjected to the power F (medium torque) of the torsion spring, the contact point of the fulcrum one (ie, the steel ball one) (f1) is relatively the aforementioned static force F (small torque) The time has increased and the total friction has increased, so there is an error value.

As shown in the third diagram (c), the basic structure of the dynamic bearing of the present invention is disclosed. And inheriting and adopting the same principle design as the third figure (a), the structure includes: a plane Huasi a, and a fulcrum b having a high and low difference setting, the fulcrum b is further distinguished by a steel ball f1 and The steel ball two f2; thereby the dynamic bearing is installed in the automatic screwdriver to take the low plane bearing, under the action of the torsion spring power F (medium torque), the force point can be transferred from the steel ball f1 to the steel ball two f2 , and can eliminate the error caused by the friction of the steel ball, and then obtain high-precision torque.

As shown in the fourth figure (a), it is disclosed that the laminated structure of more than one bearing is A schematic diagram of the basic force principle of the high torque F (high torque) of the torsion spring, the structure includes at least one layer of plane washers a, c, e and a plurality of fulcrums b, d, f alternately stacked. According to the force diagram, when the multi-layer bearing is subjected to the power F (high torque) of the torsion spring, at least two layers of flat washers a, c or more than two layers of flat washers a, c, e are required to be laminated. Construction, and with more steel beads, a f1 ~ steel ball six f6 as a layered fulcrum to separate, only It will not cause the uppermost steel ball f1 to be directly stressed and ruptured. The final result of this design is that no matter what degree of force (including large, medium and small torque) is encountered, it can exclude different stages. The frictional force caused by the force reaches the precise torque.

However, as shown in the fourth figure (b), the general planar bearing structure is disclosed. Including a flat washer a and a point b, under the action of the dynamic force F (high torque) of the torsion spring, the deformation degree of the plane washer a will increase, the contact surface of the steel ball f1 increases, and the total friction force also increases, the error The value is relatively large.

Looking at the fourth figure (c), the base of the dynamic bearing of the invention is disclosed. The basic structure, and inherits and adopts the same principle as the fourth figure (a). Therefore, the dynamic bearing of the present invention can adopt a multi-layered flat washers a, c, and e with more layers of fulcrums b having high and low differences, d, f, that is, including steel ball-f1~ steel ball six f6, so that when the dynamic bearing is actually used in the automatic screwdriver, under the action of the power F (high torque) of the torsion spring, the layers can be layered by force. Transfer and eliminate the friction, so you can get high-precision torque.

The multi-layer dynamic bearing structure disclosed above is not limited to the layer shown in the drawing. The layers are stacked and fixedly stacked, and in practical implementation, a plurality of separate or stacked dynamic bearings are arranged in the automatic screwdriver instead of the original fixed bearing type, so that a plurality of distributed singles are formed in the automatic screwdriver. Layer or multi-layer dynamic bearings, so that the force transfer dispersion provided by all the dynamic bearings can eliminate the friction error and achieve the required high torque precision.

In addition, please refer to the fourth and fifth figures together, according to the fourth figure (a) According to the principle of force, when the dynamic F (high torque) of the torsion spring is applied, the fulcrum f4 in the laminated bearing structure has shearing force at the same time, so as shown in the fourth figure (c), the present invention Dynamic The same design of the bearing in the flat washer c is a type of multiple steel balls f4, so that F max (F1) can be dispersed into two force components (ie F2 and F3), which will make the total The reduction in downforce, which in turn reduces the reaction force, allows for the best torque accuracy.

The present invention can be concluded by the above description: the total friction force and the torsion force (force force) are determined by the amount of the fulcrum (ie, the steel ball) of the dynamic bearing and the variation of the thickness (t1~t3) of at least one plane washer. The size will enable the dynamic bearing to obtain the best torque accuracy when subjected to large, medium and small torque.

Referring to the sixth embodiment, another preferred embodiment is used to illustrate the structural difference between the general planar bearing and the dynamic bearing of the present invention. According to the basic theory shown in the drawing, the plane washer a and the fulcrum b are Steel ball) In the static case, in the case of different load total friction torque (30%, 50%, 80%, 100%), and using the formula T = f μ × r, the following results can be obtained. When the friction coefficient is the same, but the radius of the steel ball is different, f μ 1>f μ 2, and T1>T2, T1 will lose a large friction force, so the torque accuracy is poor; similarly, the friction loss of T2 is small. Therefore, the torque is highly accurate.

From the proportional relationship shown in the sixth figure above, the correlation between the steel ball and the friction force is known, and it is concluded that the small torque has only a small friction force, the medium torque has a medium friction force, and the large torque has a large friction. Force, so the greater the torque, the greater the friction.

Please refer to the seventh figure, which further explains the different frictional forces generated by the number of steel balls; as shown in the seventh figure (a), referring to the aforementioned single layer consisting of the plane washer a and the fulcrum b The dynamic bearing structure, under the action of the static force F (small torque) of the torsion spring, if three steel balls are used, the friction is the smallest, and the total friction is 3 f μ; as shown in the seventh figure (b) As shown in the figure, the same single-layer dynamic bearing structure is taken as an example. In the case of the force F (medium torque), if five steel balls are used, the total frictional force = 5 f μ; and as shown in the seventh figure (c), taking the multilayer dynamic bearing structure of the present invention as an example, In the case of high torsion F (high torque), if ten steel balls are used, the friction is the largest, and the total friction is 10 f μ; thus, the more the number of steel balls used, the greater the friction loss. The relative torque accuracy is worse.

In addition, please refer to the eighth figure. In the case of actual dynamics, the automatic starter rotation is triggered by the thrust generated by the torsion spring (F _S ). As shown in the eighth diagram (a), the Hertz contact theory can be known: When the elastic body is in point contact, the contact area can be regarded as an elliptical shape; as shown in the eighth figure (b), the theory is applied to the part of the clutch (1) in the general automatic screwdriver structure, and the thrust of the torsion spring is (F _S ) is shown in the figure.

The invention particularly utilizes the elastic deformation of the steel ball when it is loaded, and reserves the deformation amount to design and explain the difference between the rolling, sliding and unloaded friction of the bearing; as shown in the ninth and tenth embodiments, for example, When the preset thrust (F _S ) is 750N, the 2.0mm steel ball will be deformed by δ mm. The δ deformation is reserved in the dynamic bearing E of the multi-layer dynamic bearing A~H in the automatic screwdriver, and the radius of the steel ball is utilized. The size and radius of rotation are used to distinguish between rolling and sliding, so that the thrust (F _S ) can obtain linear friction loss from 30% to 100%. The pressure stress formula shows that P ₀ =3N/2 π xy. The deformation amount δ, the rolling friction force F _T = ρ N / r, and the sliding friction force F _U = μ N are obtained, and the rolling friction force (T) is expressed as a torque as: T = ρ N . When x>y, the steel ball rotates in the axial direction, when F _T >F _U , the steel ball is rolling; when x>y, the steel ball rotates in the axial direction, and when F _T <F _U , the steel ball slides.

The ninth and tenth views respectively show that there are two different types of automatic screwdrivers, wherein the ninth figure discloses an upright type automatic driver partial structure, and the tenth figure discloses an elbow type automatic driver partial structure; When the dynamic bearing of the present invention is implemented in the above two types of automatic screwdrivers, more than one layer of dynamic bearings can be disposed in the automatic screwdriver under different actual torque values to achieve the effect of improving the torque accuracy; The disclosure discloses only two types of automatic screwdriver structures that are common at the present stage (not limited thereto). As shown in the ninth and tenth drawings, a plurality of dynamic bearings A~H are respectively disposed in the automatic screwdriver; According to the above 750N, the 2.0mm steel ball will produce δ mm deformation, and the δ deformation amount is reserved before the dynamic bearing E. The thrust (F _S ) for the torsion spring is 30% and 50% respectively. 80%, 100% state with the previous formula to explain: (a) when the thrust (F _S ) is 30%, A layer rolling (ρ _a ), B layer rolling (ρ _b ), C layer rolling (ρ _c), D layer rolling (ρ _d), E layer were not axial loads, F layer Receiving a load; total frictional torque load _{= N a × ρ a + N} b × ρ b + N c × ρ c + N d × ρ d. (2) When the thrust (F _S ) is 50%, the A layer slides, the B layer slides, the C layer slides, the D layer slides, the E layer rolls (ρ _e ), the F layer is not loaded; the load total friction torque = N _a × μ _a × R _a + N _b × μ _b × R _b + N _c × μ _c × R _c + N _d × μ _d × R _d + N _e × ρ _e . (3) When the thrust (F _S ) is 80%, the A layer does not move, the B layer slides, the C layer slides, the D layer slides, the E layer rolls (ρ _e ), the F layer rolls (ρ _f ); the load total friction torque =N _a ×μ _a ×R _a +N _b ×μ _b ×R _b +N _c ×μ _c ×R _c +N _d ×μ _d ×R _d +N _e ×ρ _e +N _f ×ρ _f . (4) When the thrust (F _S ) is 100%, the A layer does not move, the B layer slides, the C layer slides, the D layer slides, the E layer rolls (ρ _e ), the F layer slides; the load total friction torque = N _a × μ _a × R _a + N _b × μ _b × R _b + N _c × μ _c × R _c + N _d × μ _d × R _d + N _e × ρ _e + N _f × μ _f × R _f .

The above is the implementation of a plurality of dynamic bearings in the automatic screwdriver; It adopts composite bearing design, and uses more than one dynamic bearing to provide force dispersion. Under different load forces, there will be different total load friction, so it can be used for different torques (such as 30%, 50%, 80%). , 100%) can have different total friction torque of the load, and control the total friction torque In the range of smaller values than normal, the best and precise locking torque is achieved; however, the single-plane bearing that is generally commercially available has only a single fixed fixed and unchangeable load total friction value, so When the torque of the screw under different requirements is locked, it will not be accurate. In contrast, the present invention can be applied to the locking operation of different torque requirements through the action of the dynamic bearing, and the error value is eliminated and a more accurate torque value is obtained.

Please refer to the ninth to eleventh figures together, according to the basic theory of clutch force shown in Figure 11, and apply different clutch torque (such as 30%, 50%, 80%, 100%) to the clutch jump. For example, different tensile stresses and compressive stresses generated by the front (B layer) are taken; where F _PS is the tensile stress generated by the clutch trip, F _S is the thrust of the initial torsion spring compression clutch, F _P is the pre-locking force of the connecting shaft, F _sd is the binding force of the torsion spring to push back the clutch after the clutch trips. When the clutch 1 trips, the tensile stress of F _PS will be generated, and the tensile stress of the clutch 1 will open the connecting shaft 2, so the connecting shaft 1 is pre-locked with F _{P in} advance (that is, the negative force is pre-loaded on the connecting shaft). ), if F _PS >F _P , the dynamic bearing G layer will work; similarly, at 750N, the 2.0mm steel ball will produce δ mm deformation, and this δ deformation is reserved in the dynamic bearing E layer. In the previous question, the tensile stress F _PS at the time of stress is compared with the ninth and tenth figures in the state of 30%, 50%, 80%, and 100%, respectively: (1) When the F _PS is 30%, A layer scroll (ρ _a ), B layer scroll (ρ _b ), C layer scroll (ρ _c ), D layer scroll (ρ _d ), E layer scroll (ρ _e ), F layer is not loaded, and G layer is not affected Load, the H layer is not under load. (2) When the F _PS is 50%, the A layer slides, the B layer slides, the C layer slides, the D layer slides, the E layer rolls (ρ _e ), the F layer rolls (ρ _f ), the G layer is not loaded, H Layer scrolling (ρ _h ). (3) When the F _PS is 80%, the A layer does not move, the B layer slides, the C layer slides, the D layer slides, the E layer rolls (ρ _e ), the F layer rolls (ρ _f ), the G layer rolls (ρ _g ) , H layer scrolling (ρ _h ). (4) When F _PS is 100%, layer A does not move, layer B slides, layer C slides, layer D slides, layer E rolls (ρ _e ), layer F slides, layer G rolls (ρ _g ), H layer rolls (ρ _h ).

The above-mentioned A~G layer dynamic bearing can be finely adjusted in at least one layer in implementation. The operation, that is, replacing the steel ball used in the dynamic bearing of the layer with the steel ball having a smaller diameter, so that the steel ball of the dynamic bearing of the layer can be changed from the original rolling state to the sliding state, and the total friction is reduced. Torque for a more accurate torque output.

Please refer to the ninth to tenth and twelfth figures. According to the basic theory shown in Figure 12, when the clutch 1 in the drawing is tripped (B layer) combined with the connecting shaft 2, it will be generated. The thrust of F _sd , the thrust of the clutch 1 will hit the connecting shaft 2 , so the connecting shaft 2 is pre-locked with F _{P in} advance (that is, the negative force is pre-loaded on the connecting shaft), once F _P >F _sd , The dynamic bearing G layer will work.

In addition, please refer to the thirteenth figure, in order to obtain different loads, there are different numbers. The fulcrum is specially arranged for different combinations of steel balls, slewing ring, retaining ring, support ring and support seat in the structure of the automatic screwdriver (such as ninth and tenth figures), and discusses dynamic bearing generation for T=F×R The change situation is to improve the dynamic bearing structure, wherein: δ represents the deformation of the dynamic bearing when it is subjected to F-force, and the deformation of the next dynamic bearing; △ represents the fulcrum of the force of the plane bearing; R represents the radius of rotation; F represents the object Force.

The dynamic bearing of the present invention is provided in the actual high and low difference fulcrums, including The following various types, together with the automatic driver structure diagram shown in the ninth and tenth figures; as shown in the thirteenth figure (a), the steel balls of the same rotation radius R are set on the plane washer of the dynamic bearing, but Select the diameter of the steel ball as the fulcrum, such as the A and B layers used in the automatic screwdriver; as shown in the thirteenth (b), set the height of the steel ball on the plane Huasi of the dynamic bearing. Poor, that is, the track on the contact surface of the plane washer relative to the steel ball is set to have a curvature, For example, in the A and B layers in the automatic screwdriver; as shown in the thirteenth figure (c), the steel balls with different rotation radii R are set on the plane washer of the dynamic bearing, but the diameter of the steel balls is the same, that is, in the plane The track has different radius of rotation for the contact surface of the steel ball, such as the A and B layers used in the automatic screwdriver; as shown in the figure (d) of the thirteenth figure, different radius of rotation is set on the plane washer of the dynamic bearing. R steel balls, and the diameter of the selected steel balls are also different, such as the A and B layers used in the automatic screwdriver; as shown in the thirteenth figure (e), the supporting support is provided on the plane washer of the dynamic bearing. The ring adjusts the rotating ring 4, and the steel balls of the same diameter, that is, a support ring adjusting the rotating ring 4 with a height slightly smaller than the diameter of the steel ball in the inner edge of the steel ball, such as the C and D layers used in the automatic screwdriver; As shown in Fig. (f), the outer ring of the planar bearing of the dynamic bearing is provided with a support seat to adjust the rotating ring 5, and the steel ball of the same diameter, that is, a support seat with a height slightly smaller than the thickness of the flat washer is disposed on the outer edge of the steel ball. Rotating ring 5, such as C used in an automatic screwdriver The D layer; as shown in Fig. 13(g), is provided with a bearing fixing support 6 between the two layers of dynamic bearings. In addition to the above various methods for resisting radial deformation, this method further includes combating axial deformation, such as Used in the E and F layers in the automatic screwdriver.

Through the structural patterns of (a) ~ (g), different materials and different materials The thickness of the flat washer (t) will produce different deformation δ, using different forces (such as small, medium and large torque) to produce different deformation δ, and through different tensile and compressive stresses and different The calculation of the deformation amount produces the optimal dynamic bearing structure, and then the deformation amount δ of the material is used to calculate the load force (such as the total load tension and the total load pressure) of the full torque (including the small, medium and large torque), and is free. It is used in the automatic screwdriver to replace the original flat bearings, which can improve the accuracy of the torque.

Please refer to the ninth and fourteenth drawings together. In addition, in order to avoid the disengagement between the screwdriver head and the clutch mechanism, the torque error may occur. In particular, the screw 3 is used in the F _p to be screwed together. There are two bearings to form a fixed support against the final deformation δ, which can be axially balanced. As shown in Figure 14, where F _p is the pre-locking force, F _a is the axial force, and F _r is the radial force, while the structure of the automatic screwdriver in the ninth diagram is compared, the load at the G and H layers exceeds F. When the object is stressed, the dynamic bearing will have a role. When the load F (the object is forced by force) is removed, the generated tension will not be affected, but the radial direction will be slipped, so that the torque accuracy is increased again.

Please refer to the tenth, fifteenth and sixteenth figures together. The structure of the pre-locking force refers to the structure used for the elbow-type automatic screwdriver, and the structure of the automatic screwdriver in the tenth figure, in the G and H layers. Use the screw 3 (or nut) to screw the two dynamic bearings in a threaded manner and keep the two bearings in the concentric support structure of the shaft to reserve the axial deformation δ. This combination can obtain the axial and radial directions. To the balance; as shown in the fifteenth figure, where F _p is the pre-locking force, F _a is the axial force, and F _r is the radial force. When the load exceeds F (the object is stressed), the dynamic bearing will have The effect, when the load F (object is forced) is removed, the generated tension will have no effect, and the concentricity is better, and the radial load has been absorbed by the dynamic bearing. By using the delta generated by the radial change of the shaft, the combination can obtain the axial balance; in addition, as shown in the sixteenth figure, when the load exceeds F (the force is applied to the object) in the G and H layers, the second dynamic bearing will has an effect.

△‧‧‧ fulcrum of plane bearing force

R‧‧‧ radius of rotation

F‧‧‧The force of the object

Claims (10)

An automatic screwdriver capable of adjusting dynamic load accuracy, wherein at least one set of dynamic bearings are disposed in the automatic screwdriver, the dynamic bearing includes at least one layer of flat warrior having an unlimited thickness, and at least two or more unlimited number of surrounds The steel ball is composed of high and low fulcrum fulcrums; thereby transmitting and distributing the fulcrum at the time of force to eliminate the torque error caused by the friction force, and the best torque accuracy can be obtained under the full torque range. The automatic screwdriver capable of adjusting the dynamic load accuracy as described in the first aspect of the patent application, wherein the high and low differential fulcrum of the dynamic bearing means that any fulcrum has a preset deformation amount relative to the height of the other fulcrum. The automatic screwdriver capable of adjusting the dynamic load accuracy as described in claim 1 of the patent scope, wherein the high and low difference fulcrums of the dynamic bearing can be achieved by steel balls having different diameters. The automatic screwdriver capable of adjusting the dynamic load accuracy as described in the first paragraph of the patent application, wherein the high and low difference fulcrum of the dynamic bearing can be achieved by setting the track with different depth and shallowness on the contact surface of the plane washer relative to the steel ball. The automatic screwdriver capable of adjusting dynamic load accuracy as described in claim 1 of the patent scope, wherein the high and low difference fulcrums can be achieved by setting the orbits of different rotation radii on the plane of the plane with respect to the steel ball contact surface. The automatic screwdriver capable of adjusting the dynamic load accuracy as described in the first aspect of the patent application, wherein the position difference of the dynamic bearing can be achieved by setting the orbits of different rotation radii on the plane of the plane with respect to the steel ball contact surface, and setting the steel balls with different diameters. The automatic screwdriver capable of adjusting dynamic load accuracy as described in claim 1 is characterized in that the position difference of the dynamic bearing can be achieved by providing a support ring adjusting the rotating ring smaller than the diameter of the steel ball around the inner edge of the steel ball. An automatic screwdriver capable of adjusting dynamic load accuracy as described in claim 1 of the patent scope, wherein the dynamic axis The fulcrum of the bearing can be achieved by providing a support seat to adjust the rotating ring around the outer edge of the steel ball. The automatic screwdriver capable of adjusting dynamic load accuracy as described in claim 2, wherein the preset deformation amount includes a radial deformation amount and an axial deformation amount of the dynamic bearing. The automatic screwdriver capable of adjusting the dynamic load accuracy as described in claim 9 of the patent scope, wherein the axial deformation amount further comprises a pre-locking structure for preventing, and the shaft of the dynamic bearing is coupled with a screw or a nut of a screw. Two dynamic bearings.