TWI853644B - Three kinetic electric/pneumatic screwdrivers - Google Patents

Abstract

The present invention provides a three-kinetic-energy electric/pneumatic screwdriver, which mainly includes: a high-speed motor device, a reaction force reducing hammer device, a gear device, an asymmetric clutch device, a torsion spring device, and a connecting shaft device; in particular: the three kinetic energy sources of the screwdriver include: a high-speed motor device, a reaction force reducing hammer device and an asymmetric clutch device. The high-speed motor device provides the first kinetic energy of high speed, and the reaction force reducing hammer device increases the rotor weight of the high-speed motor device and increases the speed to obtain the second kinetic energy; the asymmetric clutch utilizes the compression torque generated by the steel balls and cam tracks at two different center distances, and the helical angle caused by the compression and rotation deformation of the torsion spring to obtain the third kinetic energy of the energy storage and ejection force; in addition, the present invention further includes a hydraulic shock absorber device, which can reduce the noise increase caused by the aforementioned significant increase in kinetic energy and achieve a buffering effect, thereby obtaining a more accurate working torque value.

Description

Three kinetic electric/pneumatic screwdrivers

The present invention relates to an improved mechanism of an electric/pneumatic screwdriver, in particular a three-kinetic-energy electric/pneumatic screwdriver.

According to the known impact power wrench (2), as shown in the first figure, the main mechanism components include: motor group (21), hammer seat group (22), and connecting shaft (23). As shown in the second figure, the impact principle is: repeated rotation and striking is called a rotary impact clutch. When the hammer (24) strikes the connecting shaft (23), it is in a closed state, generating a large torque; after the impact is completed, it is in an open state, and there is no torque. Therefore, the kinetic energy source is: the motor group + hammer seat group totaling 2 kinetic energies. The relationship between the hammer seat and the connecting shaft is like hammering a nail with a hand. The faster the hammering speed, the greater the force generated. Usually this type of tool has a pressure regulating valve, which is used to adjust the motor speed. Fast speed means high torque, slow speed means low torque, and the final speed of the tool is generally between 6000 and 9000 rpm. Advantages of this impact wrench: fast motor speed, high kinetic energy, small reaction force and simple structure. Disadvantages: When the torque reaches the set value, the hammer will produce a hammering sound, and the torque depends on the time of hand pressing. Since the kinetic energy generated is mainly derived from the speed, the speed affects the torque, causing the lock screw to be too tight and slip sometimes, and too loose and inaccurate sometimes. The general torque accuracy is 50%, and it is commonly used in tire repair factories.

As shown in the third figure, the hydraulic pulse screwdriver (3) is mainly composed of a motor assembly (31), a hydraulic pulse assembly (32), and a connecting shaft (33). As shown in the fourth figure, the hydraulic pulse principle is: when the blade (34) on the connecting shaft (33) rotates to the high pressure area (H), it is closed, generating a large torque; when it rotates to the low pressure area (L), it is closed, and there is no torque. Oil (35) is a buffering medium. When the torque is adjusted to the set value, the motor assembly (31) will automatically stop and complete the locking. Kinetic energy source: the motor assembly + hydraulic pulse assembly totals 2 kinetic energies. The basic kinetic energy principle of the hydraulic pulse screwdriver is similar to that of the impact wrench. The hydraulic pulse improves the shortcomings of the impact type. It uses hydraulic oil as a buffer medium and uses blades to make the oil produce high and low pressures. After the motor rotates at high speed, an impact pulse is generated, generating kinetic energy and a relatively low noise value, because hydraulic oil does not have the sound of hammers and connecting shafts hitting each other. However, when used, the viscosity will change due to the increase in oil temperature, and the torque will be inaccurate. The accuracy is generally about ±15%. The motor speed is about 3000~7000rpm, and the kinetic energy source speed is slightly lower than the aforementioned impact wrench.

In addition, the semi-automatic clutch screwdriver (4) is known as shown in the fifth figure, and its main mechanism components include: a motor assembly (41), a gear assembly (42), a clutch assembly (43), a torsion spring (44), and a connecting shaft (45). Kinetic energy source: The motor assembly has a total of 1 kinetic energy. As shown in Figure 6, the principle of the clutch assembly is: the symmetrically designed cam structure has the same distance between the clutch center (C) and the steel ball center (r ₁ =r ₂ ), which is called a "symmetrical clutch", where T=Fr (T=torque, F1 & F2=force, r=radius, C=center point). According to the formula, T1=F1r1, T2=F2r2, T1+T2 is the total torque of the tool (T), and T3+T4 is the hand grip force (reaction force). Since the clutch radius is symmetrical (r ₁ =r ₂ ), the action force=reaction force. As shown in FIG. 7, the torsion spring side view operation schematic diagram, the clutch assembly (43) includes a steel ball (431), a cam (432) (i.e., a lower clutch, an upper clutch), and a torsion washer seat (433). FIG. (A) is in standby mode (no torque value), the steel ball (431) of the clutch generates resistance (F) on the cam (432), the cam (432) rises, generates an upward force (F1 and F2) on the torsion spring (44), and the torsion spring (44) generates a compression force (S1 and S2); when the torsion spring (44) is in operation and force is applied, as shown in FIG. (B), the height (L) of the torsion spring (44) gradually becomes shorter, L1 = height of lower clutch, L2 = height of cam rise; when cam (432) rises to the top dead center as shown in Figure (C), it reaches the maximum torque. Due to the symmetrical cam design, when the cam (432) rises and falls, the steel ball (431) will also rise and fall synchronously, but the torsion spring (44) and the torsion washer seat (433) will not twist when rising and falling. The above action causes the clutch to rotate, so that T1 and T2 generate kinetic energy, which is the total torque (total torque) of the tool = T1 + T2; finally, the cam (432) jumps off as shown in Figure (D), and the length (L) of the torsion spring (44) returns to its original state. Summarizing the above explanation, we can know that: since there are cams and steel balls in the clutch assembly, the torsion spring makes the cam jump up and down to adjust the spring force. Generally, commercially available rechargeable screwdrivers all use semi-automatic clutches. When the screw is locked to the expected torque value, the clutch will slip (squeaking sound), and the trigger button is released to complete the operation. The accuracy will be affected by human operation and the length of time of hitting, and the torque is not accurate, with an error of about ±10~30%. Due to the large reaction force, it is generally designed as a gun-shaped tool, and the straight tool is used to lock screws below M4.

Furthermore, the known fully automatic clutch torque automatic stopper (5), as shown in Figure 8, mainly comprises: valve plate and needle (51), motor assembly (52), gear assembly (53), clutch assembly (54), torsion spring (55), and connecting shaft (56). Kinetic energy source: the motor assembly has a total of 1 kinetic energy. The principle of the clutch assembly is: symmetrical cam principle, just like the aforementioned semi-automatic clutch is symmetrical principle, but the difference is: when the torque setting value is reached, the valve plate and needle (51) will automatically stop the motor assembly (52), and the connecting shaft (56) will no longer rotate, and the locking is completed. The torque auto shut-off screwdriver is an evolution of the semi-automatic clutch screwdriver. Since the semi-automatic torque repeatability is ±10~30%, it cannot pass the ISO5393 international precision requirement standard in professional production lines. However, this generation of clutch torque auto shut-off screwdrivers can meet the requirements with an accuracy of ±0.03%. The same as the semi-automatic torque, the kinetic energy source is the motor group. The gear group is responsible for reducing the speed. By changing the speed ratio, the speed or torque can be increased. The larger the torque, the slower the speed; the smaller the torque, the faster the speed. When the torque reaches the expected setting value, the clutch group will automatically shut down the motor group (Auto Shut-off) and stop rotating to complete the locking of the screw, so the torque accuracy is high. The torsion spring is responsible for adjusting the torque value. The reaction force is large, and the machine arm (Torque Arm) must be used when locking large screws to prevent the operator from being injured.

In view of this, the inventor of this case deeply felt that the use of automatic tools is still not perfect and there is room for improvement. Therefore, relying on the design experience accumulated over the years, after continuous experiments and trials, this more practical invention was finally produced, hoping to benefit the industry and the general public.

The main purpose of the present invention is to provide a three-kinetic-energy electric/pneumatic screwdriver. By designing and providing the screwdriver with three kinetic-energy devices, the inventor provides the screwdriver with greater kinetic energy, lower back force, higher precision in operation, and a buffer when the power stops, and the clutch jumps out more smoothly, which can reduce noise, make the operator feel more comfortable, and obtain better kinetic energy and performance.

To achieve the above-mentioned purpose, the present invention provides a three-kinetic-energy electric/pneumatic screwdriver, including: a high-speed motor device, a reaction force reducing hammer device, a gear device, an asymmetric clutch device, a torsion spring device and a connecting shaft device. In particular, the kinetic energy source of the screwdriver includes: a high-speed motor device, a reaction force reducing hammer device and an asymmetric clutch device, which has three kinetic energies in total. The high-speed motor device provides the first kinetic energy of high-speed rotational power; the reaction force reduction hammer device is attached to the high-speed motor device to increase the rotor weight of the high-speed motor device and to increase the rotation speed and torque to obtain the second kinetic energy; the asymmetric clutch uses the compression torque generated by the steel balls and cam tracks at two different center distances and the helical angle caused by the compression and rotation deformation of the torsion spring to obtain the third kinetic energy of stored energy torque (ejection force).

In a preferred embodiment, the high-speed motor device has a rotor and an inner and outer seat, a needle is passed through the axis of the rotor, an air valve plate is provided at one end of the rotor and supported by a spring, and a main gear is combined at the other end of the rotor opposite to the air valve plate.

In a preferred embodiment, the reaction force reducing hammer device includes: one or more fixing screw hammers, a reaction force hammer, a hammer fixing seat, a C-ring and several steel balls. The hammer fixing seat is fixed by combining the C-ring with the reaction force hammer. The circumference of the reaction force hammer forms a concave notch, and a receiving groove is formed on one side of the notch. The fixing screw hammer is placed in the receiving groove and one end is penetrated through the circumference of the hammer fixing seat and connected and fixed by steel balls.

In a preferred embodiment, the asymmetric clutch device is composed of an upper clutch, a steel ball and a lower clutch. The surface of the upper clutch has inner and outer cam tracks with two different center distances. A steel ball is respectively provided on the two cam tracks and supported by the lower clutch.

In a preferred embodiment, the torsion spring device includes a torsion tube, a torsion tube washer seat and a torsion adjustment ring covering the torsion spring. One end of the torsion spring abuts against the lower clutch, and the other end abuts against the torsion tube washer seat. The torsion adjustment ring provides the torsion spring with a tight and loose state change.

In a preferred embodiment, a striker and a striker steel ball are provided at one end of the connecting shaft device, which are connected to the axis of the rotor, and a tool head is provided at the other end.

In a preferred embodiment, the hydraulic shock absorber includes a hydraulic outer seat, a lower clutch piston linked to the lower clutch, an upper liquid tank, a lower liquid tank and a hydraulic hole connecting the upper and lower liquid tanks in the space between the lower clutch piston and the hydraulic outer seat, an oil filling hole on the upper liquid tank with an oil filling screw, and a leak-proof oil seal against the hydraulic hole and a leak-proof washer against a return spring in the lower liquid tank.

The expected effects achieved by the present invention include: 1. Two buffer cams are added to the asymmetric clutch device to release the kinetic energy of the latter part of the pulse, so that there is a buffer after the motor stops, the pulse is smoother, and the operator feels more comfortable. 2. The asymmetric clutch device is equipped with a reaction force reduction hammer device to reduce the reaction force while retaining the high precision of the clutch. 3. When the torque of the fully automatic clutch reaches the set value, the clutch automatically jumps out and the air valve plate automatically closes the air. The torque is more accurate (±3%) and meets the ISO5393 precision requirement specifications. 4. The asymmetric clutch is set on the torque cylinder, so that the torque washer seat will be fixed and not rotate, and the torsion spring and the lower clutch will be clamped and fixed, so that the torsion spring can be twisted to generate new kinetic energy. 5. Under the condition of not reducing resistance, the elastic acceleration pushes the connecting shaft to generate rotational kinetic energy. In the process, an additional torque of stored energy is added, which increases the total torque. At the same time, the reaction force will become smaller when the same torque is locked. The actual drop test can reduce the reaction force by 25%~50%.

Usage:

(2): Impact power wrench

(21): Motor Group

(22): Hammer block assembly

(23): Connecting shaft

(24): Hammer

(3): Hydraulic pulse screwdriver

(31): Motor Group

(32): Oil pressure pulse set

(33):Connecting shaft

(34):Leaves

(35):Oil

(H): High pressure area

(L): Low pressure area

(4): Semi-automatic clutch screwdriver

(41): Motor Group

(42): Gear set

(43): Clutch assembly

(431):Steel ball

(432): Cam

(433):Torque washer seat

(44):Torsion spring

(45):Connecting shaft

(5): Fully automatic clutch torque automatic stop screw

(51): Valve plate and needle

(52): Motor Group

(53): Gear set

(54): Clutch assembly

(55):Torsion spring

(56):Connecting shaft

The present invention:

(1): Three kinetic electric/pneumatic screwdrivers

(11): High-speed motor device

(111):Rotor

(112): Chinese and foreign seats

(113):Needle

(114): Air valve plate

(115):Straight spring

(116): Main gear

(12): Reaction force reduction hammer device

(121):Fixing screw hammer

(122): Reaction hammer

(123): Hammer fixing seat

(124):C ring

(125):Steel ball

(126): Planetary gear plate

(13): Gear device

(14): Asymmetric clutch device

(141): Upper clutch

(142):Steel ball

(143): Lower clutch

(144): Cam track

(15): Torsion spring device

(151):Torsion spring

(152):Torque cylinder

(153): Torque cylinder washer seat

(154):Torque adjustment ring

(16): Connecting shaft device

(161):Firing pin

(162): Firing pin steel ball

(163): Tool head

(17): Hydraulic shock absorber

(171):Hydraulic external seat

(172): Lower clutch piston

(173): Upper liquid tank

(174):Lower liquid tank

(175):Hydraulic hole

(176): Oil filling hole

(177): Grease-filling screw

(178A): Leak-proof washer

(178B): Anti-leakage oil seal

(179):Return spring

A: Opening

B: Opening

C: Opening

(c1), (c2), (c3), (c4), (c5): Cam

The first figure is a schematic diagram of the mechanism decomposition of a common impact power wrench.

The second figure is a schematic diagram of the principle and operation of the impact power wrench in the first figure.

The third figure is a schematic diagram of the mechanism decomposition of a conventional hydraulic pulse screwdriver.

The fourth figure is a schematic diagram of the principle and operation of the hydraulic pulse screwdriver in the third figure.

The fifth figure is a schematic diagram of the mechanism decomposition of a conventional semi-automatic clutch screwdriver.

Figure 6 is a schematic diagram of the principle of the semi-automatic clutch screwdriver in Figure 5.

Figure 7 (A)(B)(C)(D) is a schematic diagram of the operation of the semi-automatic clutch screwdriver in Figure 5.

Figure 8 is a schematic diagram of the mechanism decomposition of a known fully automatic clutch screwdriver.

Figure 9 is an exploded view of the screwdriver components of a preferred embodiment of the present invention.

Figure 10 is a cross-sectional view of the overall structure of a screwdriver of a preferred embodiment of the present invention.

Figure 11 (A)(B)(C) is a schematic diagram of the device and operation of increasing the kinetic energy of a screwdriver in a preferred embodiment of the present invention.

Figure 12 (A) (B) is a schematic diagram of the device and action for increasing the kinetic energy of a screwdriver in another preferred embodiment of the present invention.

Figure 13 (A)(B)(C)(D) is a schematic diagram of a new displacement kinetic energy added to the asymmetric clutch device of another preferred embodiment of the present invention.

Figure 14 (A)(B)(C)(D)(E) is a side view of the torsion spring in Figure 12.

Figure 15 is a table showing the kinetic energy change of a screwdriver of an asymmetric clutch when locking a screw using a screw dynamic simulator.

Figure 16 is a table showing the kinetic energy change of a screwdriver with a symmetrical clutch when locking a screw using a screw dynamic simulator.

Figure 17 (A)(B)(C)(D)(E) is a reverse view and operation diagram of a hydraulic shock absorber of a preferred embodiment of the present invention.

Figure 18 is a schematic diagram of the external control of the oil pressure pulse hydraulic device of a preferred embodiment of the present invention.

Please refer to the ninth and tenth figures. The present invention proposes a three-kinetic-energy electric/pneumatic screwdriver (1), comprising: a high-speed motor device (11), a reaction force reducing hammer device (12), a gear device (13), an asymmetric clutch device (14), a torsion spring device (15) and a connecting shaft device (16). The high-speed motor device (11) comprises a rotor (111) and an inner and outer seat (112), and a needle (113) is arranged on the axis of the rotor (111). One end of the needle (113) is provided with an air valve plate (114) and a spring (115) for controlling the start and stop operation of the high-speed motor device (11). The rotor (111) has a main gear (116) at the other end opposite to the air valve plate (114). The reaction force reducing hammer block device (12) has the characteristics of low back force and high torque, and comprises one or more fixing screw hammers (121), a reaction force hammer (122), a hammer fixing seat (123), a C ring (124) and a plurality of steel balls (125); the main gear (116) of the rotor (111) is pressed into the hammer fixing seat (123) and then the reaction force hammer (122) is placed, the hammer fixing seat (123) is fixedly combined with the reaction force hammer (122) by the C ring (124), and the reaction force hammer (122) A concave notch is formed on the circumference, and a receiving groove is formed on one side of the notch. The fixing screw hammer (121) is placed in the receiving groove and one end thereof penetrates the circumference of the hammer fixing seat (123) and is connected and fixed by a steel ball (125). A planetary gear plate (126) is engaged and driven below. When the high-speed motor device (11) is started, the fixing screw hammer (121) is driven to move upward and hammer the reaction force hammer (122). When the rotation speed decreases, the fixing screw hammer (121) is moved downward and hammers the hammer fixing seat (123). The gear device (13) engages the planetary gear plate (126) upward to connect and transmit the power of the high-speed motor device (11). The asymmetric clutch device (14) is composed of an upper clutch (141), a steel ball (142) and a lower clutch (143). The lower surface of the upper clutch (141) has two inner and outer cam tracks (144) with different diameters. A steel ball (142) is respectively arranged in the two cam tracks (144) and supported by the lower clutch (143), thereby forming an asymmetric clutch mechanism. The torsion spring device (15) includes a torsion tube (152) covering the torsion spring (151), a torsion tube washer seat (153) and a torsion adjustment ring (154). One end of the torsion spring (151) is against the lower clutch (143), and the other end is against the torsion tube washer seat (153). The torsion adjustment ring (154) provides a torque increase when the torsion spring (151) is tightened, and a torque decrease when the torsion spring (151) is loosened. One end of the connecting shaft device (16) is provided with a striker (161) and a striker steel ball (162) for connecting with the axis of the rotor (111), and the other end is provided with a tool head (163) of various functions and shapes.

T=Fxr T=lma由上述動能公式得知：質量m與速度V決定動能大小，尤其速度V²，因此運用公式設計出不一樣的概念，將高速馬達裝置之轉速提高，但最終轉速降低至連接軸裝置上，以產出最大動能、最精準扭力、重量輕且反作用力小之功能。又從該動能公式得證V為速度平方比，轉速越高動能則越大，反作用力越小。依習知衝擊式扳手之錘塊原理，運用於本發明，在高速馬達裝置之轉子上新增降反作用力錘裝置，因增加了整體質量(m)且轉速 提高，使動能增大，故獲致高轉速馬達效率是最高的。 The three kinetic energy increasing devices of the three kinetic energy electric/pneumatic screwdrivers of the present invention are respectively: a high-speed motor device (11), a reaction force reducing hammer device (12) and an asymmetric clutch device (14). The high-speed motor device (11) is the first kinetic energy that provides the basic rotational power. In this example, the rotation speed is between 20,000 and 40,000 rpm. The function of the reaction force reducing hammer device (12) is to increase the rotational mass of the high-speed motor device (11) so that the kinetic energy is further increased to become the second kinetic energy, and the screwdriver has a low back force and high precision, and the repeatability can meet the ISO5393 screw locking specification for precision requirements. The principle is as follows:

T=Fxr T= l ma From the above kinetic energy formula, we know that the mass m and speed V determine the kinetic energy, especially the speed V ² . Therefore, we use the formula to design a different concept, which increases the speed of the high-speed motor device, but reduces the final speed to the connecting shaft device to produce the maximum kinetic energy, the most accurate torque, light weight and small reaction force. It is also proved from the kinetic energy formula that V is the square ratio of speed. The higher the speed, the greater the kinetic energy and the smaller the reaction force. According to the hammer principle of the impact wrench, it is applied to the present invention. A reaction force reduction hammer device is added to the rotor of the high-speed motor device. Because the overall mass (m) is increased and the speed is increased, the kinetic energy is increased, so the high-speed motor efficiency is the highest.

Please refer to the eleventh figure (A), (B), (C), which discloses a device for increasing kinetic energy of a screwdriver and a schematic diagram of its operation in accordance with a preferred embodiment of the present invention; the reaction force reducing hammer device (12) is attached to the power output direction of the rotor (111) of the high-speed motor device (11), and comprises: one or more fixing screw hammers (121), a reaction force hammer (122), a hammer fixing seat (123), a C ring (124) and a plurality of steel balls (125). It is known from the kinetic energy formula that mass (m) affects kinetic energy. During the design, the inner ring of the hammer fixing seat (123) is made of a lighter material such as aluminum, so that the high-speed motor device (11) saves more power when starting. After starting, the fixing screw hammer (121) will hammer the reaction hammer (122), so the reaction hammer (122) uses a heavier material such as steel on the outer ring, so that the high-speed motor device (11) can obtain lighter, better kinetic energy and performance.

Please refer to the twelfth figure (A) (B), which discloses the device and operation diagram of the screwdriver kinetic energy increase device of another preferred embodiment of the present invention; wherein figure (A) shows the cam structure of the conventional symmetric clutch, including a cam (c1) and a cam (c2) at opposite positions of a track (t); figure (B) shows the cam structure of the asymmetric clutch device, including two inner and outer tracks (t1, t2) that do not interfere with each other, and cams (c3), cams (c4) and two buffer cams (c5). Moreover, the distance between the cam and the center (r ₁ ≠r ₂ ) is also different from the distance between the cam and the center of the conventional symmetric clutch (r ₁ =r ₂ ). Please refer to the thirteenth figure (A)(B)(C)(D) again. The asymmetric clutch device (14) adds a new displacement kinetic energy, where the torque formula is T=Fr (T=torque, F1 & F2=force, r=radius), C=center point, and the principle is as follows: In the asymmetric cam design, the radii of _r1 and _r2 are different. According to the above formula, T1= _F1r1 , T2= _F2r2 and T3= _F3r3 , and the sum is the total torque of the tool (T1+T2+T3). Compared with the symmetric cam, a new T3 kinetic energy is added. Since the two cam radii of the asymmetric clutch device ( _r1 ≠ _r2 ), the action force ≠ the reaction force, the action force is large and the reaction force is small.

Please refer to Figure 14 (A)(B)(C)(D)(E) again, which discloses a side view of the torsion spring. The following is an explanation of the action diagram: As shown in Figure (A) when in standby mode (no torque value), the steel ball (142) of the asymmetric clutch device (14) generates resistance (F) on the cam track (144). At the same time, the cam track (144) rises to generate an upward force (F1 and F2) on the torsion spring (151), and the torsion spring (151) generates a compression force (S1 and S2). L1 = lower clutch height, L2 = cam rise height. As shown in Figure (B), when the force is applied during operation, the high-speed motor device is forced to rotate with the bearing as the center point (C). However, due to the asymmetric cam structure ( _r1 ≠ _r2 ), the radius of _r1 is smaller than _r2 . According to the above formula, F1 is greater than F2. The steel ball (142) pushes the clutch (143) down obliquely like the wheel of a car. The radius of _r1 is smaller, and the speed of the steel ball (142) rotating is relatively faster. On the contrary, r1 is smaller. ₂ The radius is larger, the steel ball (142) rotates slower, and the two rolling steel balls (142) will produce an inner wheel difference due to the asymmetric track. The steel ball (142) starts to rotate and drives the lower clutch (143) to rotate, producing an inner wheel difference and speed difference similar to when a car rotates, and gradually twists the torsion spring (151), generating a helical angle ( α3 ) and starting to store energy. As shown in Figure (C), when the cam track (144) rises to the top dead center (i.e., the highest point), it runs to the maximum torque, and releases kinetic energy at the same time when T1 and T2 are maximum, generating a maximum torsional internal thrust (T3), which is displacement kinetic energy. Therefore, the total torque (total torque) of the screwdriver = T1+T2+T3, and the force is greater. As shown in Figure (D), the cam track (144) of the asymmetric clutch device (14) has been disengaged. At this time, the resistance of the rolling steel ball (142) and the cam track (144) immediately becomes zero resistance, and the asymmetric track produces an inner wheel difference and slips, just like a pull-back toy car. When the hand is about to let go of the pull-back toy car, the spring releases the kinetic energy stored before, causing the wheels to start rotating and moving forward. Therefore, there are two forces of different natures acting in the action, that is, an additional elastic potential energy is emitted F3. As shown in Figure (E), the operation stops, the locking is completed, and the torsion spring (151) returns to its original state.

Please refer to Figures 15 and 16, which are tables showing the kinetic energy changes of a screwdriver with a symmetric clutch and a screwdriver with an asymmetric clutch when locking a screw using a screw dynamic simulator, to prove that the asymmetric clutch device has an additional kinetic energy of a spring force. As shown in Figure 15, the speed of the thick black line suddenly dropped by 30rpm at 0.13 seconds, proving that there was a slip phenomenon. Generally, a clutch with proportional linearity cannot have a slip phenomenon. At 0.14 seconds, the speed of the thick black line and the torque value of the thin gray line overlap and rise to the maximum value. This phenomenon means that after slipping, the stored elastic potential energy will be ejected at the same time, generating the speed and maximum torque value (the total force of T1+T2+T3), and then the motor stops, and the speed and torque return to zero. As shown in Figure 16, the kinetic energy change table of the conventional symmetrical clutch is shown, in which the thick black line is the speed line. When the motor is loaded, the speed slowly drops to 450rpm, and then stops rotating at 0.7 seconds. The thin gray line is the torque line. The clutch increases linearly and proportionally. The maximum torque value is around 6N.m. There is no slippage and no ejection force, which is different from the asymmetric clutch.

Please refer to the hydraulic shock absorber structure and operation diagram shown in Figure 17 (A)(B)(C)(D)(E); the hydraulic shock absorber (17) is arranged above the torque cylinder (152) to reduce the rebound force of the torsion spring (151), and includes: a hydraulic outer seat (171), a lower clutch piston (172) linked to the lower clutch (143), the lower clutch piston (172) and the hydraulic outer seat (171 ) has an upper liquid tank (173), a lower liquid tank (174) and a hydraulic hole (175) connecting the upper and lower liquid tanks (173, 174), an oil filling hole (176) is provided on the upper liquid tank (173), and an oil filling screw (177) is provided therein, and a leak-proof oil seal (178B) is provided in the lower liquid tank (174) to abut against the hydraulic hole (175) and a leak-proof washer (178A) is provided to abut against the return spring (179). The leakproof oil seal (178B) is made of a soft material such as rubber to block the hydraulic hole (175) to achieve a good sealing effect. The leakproof washer (178A) is made of a hard material such as metal to support the soft leakproof oil seal (178B) and is supported by a return spring (179) below. The set of leakproof oil seal (178B) and leakproof washer (178A) is affected by the displacement of the lower clutch piston (172) to control the flow rate of the liquid and the speed of the upper and lower movements of the lower clutch piston (172). As shown in Figure (A), the screwdriver is in the standby state; as shown in Figure (B), after the screwdriver is started, when the lower clutch rises, the cam and the lower clutch piston (172) rise, and the liquid in the upper liquid tank (173) pushes the leakproof oil seal (178B) and the leakproof washer (178A) downward from the hydraulic hole (175) to form an opening A, so that the liquid flows from the opening A to the lower liquid tank (174), and the return spring (179) descends; as shown in Figure (C), when the cam rises to the highest point (top dead center), the opening B of the leakproof oil seal (178B) forms the maximum liquid flow rate, This state is the maximum torque of the screwdriver locking the screw; as shown in Figure (D), when the cam jumps off, the oil injection screw (177) will block the leakproof oil seal (178B), so that the lower clutch piston (172) does not move. At this time, the gap of opening C returns to be smaller than that of opening B, and the liquid flows back from the lower liquid tank (174) to the upper liquid tank (173). The return spring (179) is reset, and the lower clutch piston (172) also slowly descends to return to its original position. At this time, the screwdriver is about to lock the screw; as shown in Figure (E), the screwdriver has completed the screw locking and returned to the standby state, and can be locked again.

Based on the above, since the lower clutch piston (172) will reduce the downward push force of the torsion spring (151) and the lower clutch (143), the torsion spring (151) will not cause the steel ball (142) and the lower clutch (143) to continuously collide with each other, thereby reducing the noise value. In particular, when the screwdriver locks a screw each time, the lower clutch only trips once (One Pulse), without continuous tripping, and automatically stops (Auto Shut-Off) when the torque value is reached. The torque accuracy is high, which is different from the continuous pulse (continuous tripping phenomenon) of general hydraulic pulse tools.

In addition, for the screwdriver structure of the present invention, the torsion spring pressure is divided into large and small torques, and the rotation speed is fast and slow, so two mechanical structures are designed. The internal adjustment tool is required for faster rotation speed and large torque; the external adjustment tool is required for slower rotation speed and small torque. Please refer to Figure 18. The screwdriver of the present invention uses an external torque adjustment structure. The torque can be easily adjusted by rotating the torque adjustment ring. Because the compression torque spring method is used, the compression force can be linearly proportional, and the target torque value can be obtained very accurately, which can pass the ISO5393 precision requirement specification.

From the above description, it can be seen that the present invention adopts a high-speed motor device, a reaction force reduction hammer device and an asymmetric clutch device to form a design with three kinetic energy additions, which is superior to the conventional ones in terms of speed and torque output. At the same time, the use of a hydraulic shock absorber device can further reduce the noise generated by the above-mentioned substantial increase in speed and torque, effectively reducing the number of clutch tripping times when locking the screwdriver to one, and at the same time, simultaneously improving the torque accuracy when locking the screw.

However, the above is only the best feasible embodiment of the present invention, so any equivalent structural changes made by applying the present invention specification and the scope of patent application should be included in the patent scope of the present invention.

(1): Three kinetic electric/pneumatic screwdrivers

(11): High-speed motor device

(111):Rotor

(112): Chinese and foreign seats

(113):Needle

(114): Air valve plate

(115):Straight spring

(116): Main gear

(12): Reaction force reduction hammer device

(121):Fixing screw hammer

(122): Reaction hammer

(123): Hammer fixing seat

(124):C ring

(125):Steel ball

(126): Planetary gear plate

(13): Gear device

(14): Asymmetric clutch device

(141): Upper clutch

(142):Steel ball

(143): Lower clutch

(15): Torsion spring device

(151):Torsion spring

(152):Torque cylinder

(153): Torque cylinder washer seat

(154):Torque adjustment ring

(16): Connecting shaft device

(161):Firing pin

(162): Firing pin steel ball

(163): Tool head

(17): Hydraulic shock absorber

(171):Hydraulic external seat

(172): Lower clutch piston

(173): Upper liquid tank

(174):Lower liquid tank

(178A): Leak-proof washer

(178B): Anti-leakage oil seal

(179):Return spring

Claims (3)

A three-kinetic-energy electric/pneumatic screwdriver includes: a high-speed motor device, providing a first kinetic energy, having a rotor and a middle outer seat, a needle is passed through the rotor axis, and a valve plate is provided at one end of the needle, a flat spring is provided above the valve plate to resist, and a main gear is combined at the other end of the rotor; a reaction force reducing hammer device, providing a second kinetic energy, attached to the power output direction of the rotor of the high-speed motor device and penetrated by the rotor, including a fixing screw A hammer, a reaction hammer, a hammer fixing seat, a C ring and a plurality of steel balls. The hammer fixing seat is fixed by the C ring and the reaction hammer. A concave notch is formed on the circumference of the reaction hammer. A receiving groove is formed on one side of the notch. The fixing screw hammer is placed in the receiving groove. One end of the fixing screw hammer passes through the hammer fixing seat and is connected and fixed by the steel ball. It passes through the rotor end edge of the reaction hammer block device and then engages with a planetary gear plate to transmit. A gear device is used to The combined output of the first kinetic energy and the second kinetic energy includes one or more gears engaging the planetary gear disc to connect the power output of the high-speed motor device; an asymmetric clutch device provides a third kinetic energy, superimposing the first kinetic energy and the second kinetic energy, including an upper clutch, a steel ball, and a lower clutch. The surface of the upper clutch has two inner and outer cam tracks with different center distances. The steel ball is respectively arranged on the inner and outer cam tracks, and the lower clutch is used as a support. A torsion spring device includes a torsion spring, one end of which is against the lower clutch and the other end is against a torque cylinder washer seat, and is covered with a torque cylinder and a torque adjustment ring to control the tightness of the torsion spring; and a connecting shaft device, a striker is provided at one end to abut against the needle and is connected to the lower clutch, the striker is combined with two striker steel balls to limit displacement, and a tool head is provided at the other end of the connecting shaft device. The three kinetic electric/pneumatic screwdrivers as described in claim 1 further include a hydraulic shock absorber, including a hydraulic outer seat, a lower clutch piston linked to the lower clutch, an upper liquid tank, a lower liquid tank and a hydraulic hole connecting the upper and lower liquid tanks in the space between the lower clutch piston and the hydraulic outer seat, an oil filling hole on the upper liquid tank, an oil filling screw disposed therein, a leak-proof oil seal against the hydraulic hole and a leak-proof washer against a return spring disposed therein. As described in claim 1, the three kinetic electric/pneumatic screwdrivers, wherein the reaction force reducing hammer device includes one or more fixed screw hammers, which are equally divided and arranged on the peripheral surface of the hammer fixing seat.

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