TWM486521U - Two-stage locking electric screwdriver - Google Patents

Description

Two-stage lock with electric screwdriver

This creation is about the improvement of the electric screwdriver, especially the two-stage locking electric screwdriver with external adjustment torque, convenient adjustment, accurate torque, energy saving and reduced parts number and cost saving.

According to the lock wire (plug) locking technology, it plays an indispensable role in various industries and modern processes. Especially the screw (plug) assembly technology in the fields of automobile, aviation aerospace and bolt manufacturing is particularly important.

SCHATZ, which has accumulated more than 50 years of technical experience, has been committed to developing various bolt assembly and quality assurance solutions. It has become the industry standard and even the technical standards have been the current international or national standards or guidelines; especially Volker Schatz In his book "10 Step for Reliable Bolted Assembly", the doctor detailed 10 steps that affect all the factors in the assembly program, and affects the bolt connection. The causal relationship of fastening quality was analyzed and studied. These 10 steps can be made into a step checklist for monitoring the degree of sophistication of the method implemented during the tightening of the bolt joint. Of course, these 10 steps can also be used as guidelines for developing current standards that reflect the most sophisticated quality systems. Through this book, the quality assurance of the lock is raised to the highest level and meets the current standards and methods.

In the book, the tightening method is to install the fastening of the threaded secondary connection. One of the most important aspects of the strategy. For each bolting operation that assembles the assembly together, a guide is required to describe the steps to be taken when tightening and the measurement data to be used. To this end, the parameters of the assembly step should be calculated based on the abstract model. Since it is an abstract model, these parameters are only approximations of the actual conditions. The series of assumptions and estimates provided here can be used as the basis for fastener connection design. In addition, the results of charts, standards, and tests often fail to reflect the factors that affect assembly in actual assembly operations, and these results are often used as the basis for assembly operations. The tightening specifications currently used in production typically specify a torque with a corresponding tolerance range, or a cornering method that uses a tightening fastener to rotate the fastener to a certain angle to achieve a predetermined torque. When looking at the bolting fastening process, it seems very simple at first glance. When a fastening connection is made using a rotary power tool, the bolt is screwed into the screw hole until the head contacts the component to be mounted, and the wrench tool suddenly stops rotating. In this process, most of the time is used to screw in the fasteners. In the actual assembly process, that is, when two or more parts are connected together, this action is instantaneously utilized in 1 second. Completed.

Because the locking assembly process is quite short and fast, the implementation of the bomb The locking work of the material connection is prone to paralysis. As shown in the first figure, elastic deformation occurs when the fastener is momentarily locked. The elastic material is plastically deformed, like a spring. Even if the screw (bolt) is locked and fixed within its elastic limit, it may also cause loosening of the locking connection, so-called clamping force loss.

Referring to the second figure (A), (B), by the Schatz laboratory in Germany The multi-functional bolt fastening analysis system analyzes the performance of the screw (bolt) for the screw (plug) lock. The graphical analysis of the second figure (A) shows that the bolt lock is thinner than the bolt length. can. The second figure (B) shows the performance of the bolts being fixed to a material that is thicker than the length of the bolt.

It can be seen from the description that the meaning expressed in the above second figure (B) is as follows. When the screw (plug) is rotated at a very fast torque until the lock is completed, although the torque remains within the tolerance, in reality, the locking operation is incomplete and the screw (plug) is not properly fixed. The significance shown in the second diagram (A) is that if the two-stage locking will avoid the situation of the second figure (B), the screw (bolt) lock is fixed correctly and completely tight.

In addition, Xi Jian's electric screwdriver, for the torque adjustment section, can be divided into internal adjustment Torque and external torque. Please refer to the third figure. The torsion spring of the internal adjustment type is set inside (that is, between the coupling shaft and the torque cylinder), and the outer part is combined with a torsion sheath to cover the operation of adjusting the torque. The torsion spring is located inside the structure, so a specially designed torque wrench (or tool) must be used to rotate the special angle to adjust the torque. Once the special wrench (or tool) is lost, the torque cannot be adjusted; the internal torque is adjusted. Although it is not easy to achieve in the adjustment, the advantage is that the motor does not change the no-load current due to the torque of the clutch, so it is more energy efficient.

Secondly, the externally-torque torsion spring is also disposed inside, but externally There is a torque adjustment ring (commercially available for this type). In operation, the hand can be adjusted directly outside, which is quite convenient; but the disadvantage is that when the motor starts, it will adjust to the torque or the hour, and the no-load current will follow. The torque varies, so it consumes more power.

Furthermore, in general, in addition to the motor, the electric screwdriver has at least a gear set and The combination group and the screwdriver head group, whether the internal adjustment type or the external adjustment type torque are in the starting operation, are driven by the motor to drive the gear set, and then drive the clutch group and the screwdriver head group to operate, which increases the rotating weight and generates power consumption. .

The primary purpose of this creation is to provide a two-stage locking electric screwdriver. By designing an internal tooth clutch with internal tooth staggered and misaligned cam, the inner ring track of the cam can be firstly provided with a torque to achieve the pre-lock function. And during operation, when the cams of the inner and outer ring tracks are staggered, a maximum torque is generated to achieve a perfect locking effect.

Another object of the present invention is to provide a two-stage locking electric screwdriver, thereby achieving direct adjustment of the torsion force and timely replacement of the torsion spring, thereby achieving the effect of accurately improving the torque accuracy.

A further object of the present invention is to provide a two-stage locking electric screwdriver, thereby greatly reducing the number of parts constituting the electric screwdriver, so as to achieve the substantial benefits of cost reduction and power saving.

In order to achieve the above objectives, the creator of the case designed a brand new two-stage locking electric screwdriver. The electric screwdriver has a set of matching housings on the outside, and at least includes a motor group in the housing to provide a power source. a clutch set coupled to the motor and driven to operate, the clutch set having power transmission and shifting action, and providing a two-stage torque output; a sub-head set, driven by the clutch set, and providing various screwdriver heads Plug-in connection; a board unit for providing operation start control of the motor for the electric screwdriver, and having the function of preventing button reset; and a control group having a micro-controller (MCU) board, and A source of electrical power that provides the required power.

The motor group described above further includes: a motor, an accelerator/supercharger, and the shaft of the motor power output is provided with an accelerator/supercharger.

Preferably, the motor described above employs a brushless motor.

The accelerator/supercharger described above includes one or more bearings (or sleeves) of a certain proportion by weight and made of metal.

The clutch group further includes: an internal tooth clutch, a lower clutch, an adapter shaft, a torsion tube, a torsion spring, and a torsion sheath; the internal tooth clutch is a star gear type formed by combining a gear and a toothed disc on one side, and a motor The rotating shaft is coupled and driven, and the other side is provided with a set of staggered (inner and outer ring) planetary orbits, and a cam surface design with misaligned convex portions on the planetary orbits, and steel balls are arranged on the planetary orbits of the group. The lower clutch is engaged with the cam surface of the internal tooth clutch, the adapter shaft is disposed on the lower clutch and one end is coupled to the star gear of the internal tooth clutch, and the other end of the adapter shaft is provided with a torque cylinder, and the The torsion tube is sheathed with a torsion spring and covered with a torsion sheath.

The above-mentioned screwdriver head group has a connecting shaft and is coaxially connected with the adapter shaft in the clutch group, and the connecting shaft has a coupling groove for providing various types of screwdriver head insertion and connection, and three slots are provided in the slot. Steel ball for positioning.

The shape of the groove of the above-mentioned coupling groove may be any geometric shape, such as any one of a circular shape, a square shape and a polygonal shape.

The power source described above may be a rechargeable battery.

The electric screwdriver described above further includes a torque adjustment wrench.

The embodiments of the present invention are described below in conjunction with the drawings. The following examples are set forth to illustrate the present invention and are not intended to limit the scope of the present invention. Anyone skilled in the art can make some changes and retouching. The scope of protection of this creation is subject to the definition of the scope of the patent application attached.

(1)‧‧‧Electric screwdriver

(10) ‧‧‧Shell

(20)‧‧‧ Motor Group

(21)‧‧‧Motor

(211) ‧‧ ‧ shaft

(22)‧‧‧Accelerator/supercharger

(30)‧‧‧Clutch Set

(31)‧‧‧Internal clutch

(311)‧‧‧ Gears

(312)‧‧‧ toothed disc

(32)‧‧‧ Lower clutch

(33)‧‧‧Transfer shaft

(34)‧‧‧Torque cylinder

(35)‧‧‧Torque spring

(36)‧‧‧Torque sheath

(37) ‧‧‧ cam surface

(371) ‧‧‧ convex

(372)‧‧‧ Steel Balls

(40) ‧‧‧Starter head group

(41)‧‧‧ Connecting shaft

(42) ‧ ‧ ‧ screwdriver head

(411) ‧‧‧ Combination slot

(412)‧‧‧ Steel Balls

(50) ‧‧‧ board unit

(60) ‧‧‧Control Group

(61)‧‧‧ board

(62) ‧‧‧Power source

(70)‧‧‧Torque adjustment wrench

The first figure is a schematic view of a known screw (bolt) locking elastic material.

The second figure (A) is a graph showing the performance of a screw (plug) that is thinner than the length of the screw (bolt).

The second figure (B) is a graph showing the performance of a screw (tether) that is thicker than the length of the screw (bolt).

The third figure is a schematic diagram of the adjustment torque of a known internal adjustable torque electric screwdriver.

The fourth figure is a construction diagram of the electric screwdriver of a preferred embodiment of the present invention.

The fifth figure is a structural view of the internal tooth clutch of a preferred embodiment of the present invention.

The fifth figure (A) is an action diagram of the internal gear unit of the preferred embodiment of the present invention (1).

The fifth figure (B) is an action diagram of the internal gear unit of the preferred embodiment of the present invention (2).

The fifth figure (C) is an action diagram of the internal gear unit of the preferred embodiment of the present invention (3).

The fifth figure (D) is an action diagram of the internal gear unit of the preferred embodiment of the present invention (4).

The fifth figure (E) is an action diagram of the internal gear unit of the preferred embodiment of the present invention (5).

The sixth figure is a schematic diagram of the torque adjustment of a preferred embodiment of the present invention.

The seventh figure is a schematic diagram of the lock of the electric screwdriver of the present invention.

The eighth figure is a schematic diagram of the lock of a general electric screwdriver actually applied to a dynamic torque tester.

The electric screwdriver (1) is of a charging type and has a set of matching housings (10) on the outside, and the form of the housing (10) is not limited, such as an upright type, a gun type, etc., and the present embodiment is a gun type. For example, the housing (10) is provided with at least a motor group (20), an internal clutch group (30), a driver head group (40), a plate unit (50), and a control group (60).

The motor unit (20) further includes: a motor (21), an accelerator/supercharger (22), and the motor (21) preferably uses a brushless motor, but not limited thereto, and the power output shaft (211) is provided with an accelerator/supercharger (22) comprising one or more bearings (or sleeves) of a certain proportion of weight and made of metal; the accelerator/supercharger is implemented (22) ) is disposed at the position of the power output shaft (211) of the motor (21) to achieve the effect of slow start and running acceleration, thereby multiplying the horsepower of the motor, but the power consumption is a little, thereby shortening the time for locking the screw Increase work efficiency.

The clutch set (30) further includes: an internal clutch (31), a lower clutch (32), an adapter shaft (33), a torsion cylinder (34), a torsion spring (35), and a torsion sheath (36); As shown in the fifth figure, the internal tooth clutch (31) is a star gear type formed by combining a gear (311) and a toothed disc (312) on one side, and is coupled with the rotating shaft of the motor (21) and driven to operate, and the other side is driven. In order to provide a set of interlaced (inner and outer ring) planetary orbits, and a cam surface (37) having a misaligned convex portion (371) on the planetary orbit, a steel ball (372) is disposed on the set of planetary orbits, The lower clutch (32) is in engagement with the cam surface of the internal tooth clutch (31), and the adapter shaft (33) is disposed through the lower clutch (32) and has one end coupled to the star gear of the internal tooth clutch (31). The power transmission and shifting action of the motor (21), the other end of the adapter shaft (33) is sleeved with a torsion cylinder (34), and the torsion cylinder (34) is sheathed with a torsion spring (35), and then Covered by a torsion sheath (36), which can set the required torque value, and also provides the user with the ability to adjust the torque value to a large or small value after the torque sheath (36) is removed. Further torsion spring (35) of the replacement, attachment screws serve to enhance the accuracy and quality.

The cam surface (37) of the internal tooth clutch (31) is as shown in the fifth figure, The cam surface (37) has inner and outer ring planet orbits, and is disposed on the inner and outer ring rails in a proper position: the convex portions (371) of the two ridges correspond to each other, and respectively abut on the edges of the inner and outer ring planet orbits. And the two convex portions (371) are divided into different shapes, and the two steel balls (372) are respectively operated on the inner and outer ring planetary orbits with a three hundred and sixty degree circular motion and do not affect each other.

a screwdriver head set (40) having a connecting shaft (41) disposed in the driver head set (40) and coaxially coupled to the adapter shaft (33) rod in the clutch pack (30); the connecting shaft (41) There is mainly a coupling groove (411) for providing various types of screwdriver heads (42), and the shape of the groove of the coupling groove (411) can be any geometric shape to match the joint end of the conventional common screwdriver head. The shape of the head, such as any one of a circular shape, a square shape and a polygonal shape, is not limited herein, and three steel balls (412) for positioning the clamp are provided in the groove to synchronously and stably clamp the screwdriver head (42).

The plate unit (50) is used to provide the operation start control of the electric screwdriver (1) and has the function of preventing the button from being reset.

The control group (60) has a board (61) of a microcontroller (MCU) and a power source (62) for supplying required power. In this embodiment, a rechargeable battery is used, but this is not limit.

According to the above-mentioned electric screwdriver of the present invention, in operation, when the motor (21) is started, the internal clutch (31) is rotated to drive the screwdriver head (42) to rotate; the cam surface of the internal clutch (31) The steel ball (372) and its convex part (371) located on the inner ring planet orbit will first trip to generate a torsion force, which is the torque value of the pre-locking function; then continue to rotate, when the inner and outer ring planet orbits After the steel ball (372) and the corresponding convex portion (371) are simultaneously tripped, a maximum torque is generated, so that the screw is locked tighter and reaches the pre-preg The standard value of the period; in this way, the entire locking effect and quality can be perfected.

Please refer to the fifth figure (A)~(E) together to show the respective movements of the cam surface (37) and the two steel balls (372) of the internal tooth clutch (31); The two convex portions (371) on the outer ring planetary track are a loop stroke having a top dead center and a bottom dead center continuously, and the loop travel includes at least the following stage travel: as shown in the fifth figure (A), the first The stroke provides the control of the torque of the electric screwdriver. The outer R angle is designed. At this time, the steel ball (372) on the outer ring has entered the R angle outside the outer ring convex portion (371); as shown in the fifth figure (B) For the second stroke, a pre-locking function is provided, at which time the steel ball (372) of the outer ring has been advanced to a flat stroke, while the steel ball (372) of the inner ring has entered the R angle outside the inner ring convex portion (371), and At this time, a torque value is obtained; as shown in the fifth figure (C), it is the third stroke, at which time the steel ball (372) of the outer ring travels to the parallel end, and the steel ball (371) of the inner ring continues to crawl the inner ring convex portion. (371); as shown in the fifth diagram (D), the fourth stroke, at this time, the inner and outer rings of the steel ball (372) crawl to the highest top dead center of the convex portion (371), and a maximum torque is generated at this time. Value; as shown in the fifth figure (E) , The fifth stroke, the outer ball (372) rapidly falls to the maximum dead point, while the inner race of the ball (372) is slowly dropped into the top dead point, when the lock is attached to complete.

If different speeds, pre-locking torque or maximum torque are required, the corresponding angles of the two convex portions can be changed. As shown in the fifth figure, the two convex portions (371) on the inner and outer ring planetary orbits are at the same diameter. On the line, if the convex portion (371) of the inner ring is offset by an angle in a clockwise direction, the angle between the convex portion (371) and the convex portion (371) of the outer ring becomes smaller, and the rotation speed becomes slower; if the inner ring is counterclockwise When the convex portion (372) is offset by an angle, the angle between the convex portion (371) and the convex portion (371) of the outer ring becomes larger, and the rotational speed becomes faster; thereby satisfying a more diverse need for the use of the lock.

Please refer to the sixth figure. The torque adjustment method of the electric screwdriver of the present invention is as follows: the torsion sheath (36) is loosened and then removed, and then the torque adjustment wrench (70) is gently pushed in. Turning the torque adjustment wrench (70) clockwise torque becomes larger, counterclockwise torque becomes smaller, depending on the demand, after the adjustment is completed, the torque adjustment wrench (70) is taken out, and finally the torque sheath (36) is rotated back, and the reply is confirmed to be correct. position.

According to the above, the electric screwdriver of the present invention is an externally-adjusted torque, and the torsion adjustment method is extremely convenient in operation, and the advancement is high and the torque precision is also better than the known internal adjustment torque.

In addition, due to the unique design of the clutch set and the internal clutch of the electric screwdriver, the gear unit and the clutch group of the same unit of the conventional electric screwdriver are less in the constituent components, so that the relative energy can be manufactured. The cost is reduced and the assembly is fast. At the same time, when the electric screwdriver is used, the motor can easily drive the screwdriver to operate, and the power saving effect is achieved.

Finally, please refer to the seventh and eighth figures together. The eighth picture shows the general electric screwdriver locking process in the state dynamic torque testing machine. It can be clearly seen that the locking process is very simple and always locked. The seventh figure is the new two-stage locking electric screwdriver. It can be clearly seen from the figure that the first-stage locking (so-called pre-locking) and the second-stage locking fixing are completed. It can be seen that the two-stage locking process presented by the dynamic torque tester echoes the so-called perfect lock in Schatz's book.

(1)‧‧‧Electric screwdriver

(10) ‧‧‧Shell

(20)‧‧‧ Motor Group

(21)‧‧‧Motor

(211) ‧‧ ‧ shaft

(22)‧‧‧Accelerator/supercharger

(30)‧‧‧Clutch Set

(31)‧‧‧Internal clutch

(311)‧‧‧ Gears

(312)‧‧‧ toothed disc

(32)‧‧‧ Lower clutch

(33)‧‧‧Transfer shaft

(34)‧‧‧Torque cylinder

(35)‧‧‧Torque spring

(36)‧‧‧Torque sheath

(40) ‧‧‧Starter head group

(41)‧‧‧ Connecting shaft

(42) ‧ ‧ ‧ screwdriver head

(411) ‧‧‧ Combination slot

(412)‧‧‧ Steel Balls

(50) ‧‧‧ board unit

(60) ‧‧‧Control Group

(61)‧‧‧ board

(62) ‧‧‧Power source

Claims (9)

A two-stage locking electric screwdriver has a set of matching housings on the outside, and at least includes a motor group for providing a power source in the housing; a clutch set coupled to the motor and driven to operate The clutch set has power transmission and shifting action, and provides two-stage torque output; a sub-head group, driven by the clutch group, and providing various types of screwdriver head insertion and connection; a board unit for providing an electric screwdriver The motor is activated and controlled, and has the function of preventing button reset; and a control group having a micro-controller (MCU) board and a power source for supplying required power. The two-stage locking electric screwdriver according to claim 1, wherein the motor group further comprises: a motor, an accelerator/supercharger, and the shaft of the motor power output is provided with an accelerator/supercharger. The two-stage locking electric screwdriver according to item 2 of the patent application scope, wherein the motor preferably uses a brushless motor. The two-stage locking electric screwdriver according to claim 2, wherein the accelerator/supercharger comprises one or more bearings (or sleeves) of a certain proportion by weight and made of metal. The two-stage locking electric screwdriver according to claim 1, wherein the clutch group further comprises: an internal tooth clutch, a lower clutch, an adapter shaft, a torque cylinder, a torsion spring, and a torsion sheath; the internal tooth clutch is one side The planetary gear type formed by combining the gear and the toothed disc is coupled with the rotating shaft of the motor and driven, and the other side is provided with a set of interlaced (inner and outer ring) planetary orbits, and the planetary orbit is provided with a misaligned convex portion. The cam surface design is provided with steel balls on the set of planetary orbits, and the lower clutch is matched with the cam surface of the internal tooth clutch, and the adapter shaft is disposed The lower clutch is coupled to the star gear of the internal tooth clutch, and the other end of the adapter shaft is sleeved with a torsion tube, and the torque tube is sleeved with a torsion spring and covered with a torsion sheath. The two-stage locking electric screwdriver according to claim 1, wherein the screwdriver head group has a connecting shaft and is coaxially connected with the adapter shaft in the clutch group, and the connecting shaft has a variety of screwdrivers. The joint is inserted into the joint groove, and three steel balls for positioning the clip are arranged in the groove. The two-stage locking electric screwdriver according to claim 6 is characterized in that the shape of the groove of the coupling groove can be any geometric shape, such as any one of a circular shape, a square shape and a polygonal shape. The two-stage locking electric screwdriver according to the first aspect of the patent application, wherein the electric source can be a rechargeable battery. The two-stage locking electric screwdriver according to the first aspect of the patent application, wherein the electric screwdriver further comprises a torque adjustment wrench.