CN103148081A - Unlockable nut in paster-type cantilever beam composite bending-vibration working mode - Google Patents

Abstract

The invention discloses an unlockable nut of a patch type cantilever beam compound bending vibration working mode, which belongs to the field of fasteners and transmission parts connected by thread pairs. It is to conveniently, quickly and flexibly realize the conversion and control of the two working states of self-locking and unlocking between thread pairs. On the outer circular surface of the nut base in the cantilever beam state, there are a plurality of planes opposite to each other around the circumference, and each plane is provided with a piece of its exciting type expansion and contraction piece, and each piece of it is excited type expansion and contraction One plane of the sheet is connected to the plane; the expansion and contraction direction of the other-excited telescopic sheet is parallel to the axis of the nut matrix in the state of the cantilever beam; the other-excited driving mode of multiple other-excited telescopic sheets is the traveling wave excitation mode or Standing wave excitation mode of operation. The present invention can change the self-locking working state of the nut base body to the unlocking working state when its exciting expansion plate inputs its driving signal, that is, the friction coefficient between thread pairs is greatly reduced, and the friction between the nut base body and the screw rod can be greatly reduced. The self-locking working state disappears.

Description

Unlockable Nuts for SMD Cantilever Beam Composite Flexural Vibration Working Mode

technical field

The invention belongs to the field of fasteners and transmission parts connected by thread pairs.

Background technique

Fasteners and transmission parts based on thread pairs are widely used in equipment, systems, devices and mechanisms in various industries today. For the thread pair connection pair, there are mainly two working states, which are the thread self-locking state and the non-self-locking state, and the latter can also be called the unlocking state. For the self-locking working state of the thread pair, the thread pair used should generally meet the thread self-locking conditions, that is, the thread lead angle is smaller than the equivalent friction angle between the thread pairs. The main application occasions are fastening of parts, sliding transmission guide rails and Jacks and other aspects of force transmission; for the unlocking working state of the thread pair, that is, satisfying that the thread lift angle is greater than the equivalent friction angle between the thread pairs, it mainly uses the movement and power output of the screwing transmission system between the nut and the screw, which is specifically reflected in The following three aspects, one is to realize the conversion between rotary motion and linear motion, the other is to adjust the mutual position of various parts in the system, and the third is to obtain a larger output thrust with a smaller input torque. At present, for the conversion and control of the two working states of self-locking and unlocking between thread pairs, it is often necessary to use a self-locking nut with self-locking function and a corresponding unlocking mechanism to work together. The mechanism of self-locking and unlocking state conversion function has problems such as complex structure, cumbersome operation, and high production cost, which limits the application occasions of threaded auxiliary fasteners and transmission parts.

Contents of the invention

In order to conveniently, quickly and flexibly realize the conversion and control of the two working states of self-locking and unlocking between threaded pairs, the present invention proposes an unlockable nut in the compound bending vibration working mode of a patch type cantilever beam.

The unlockable nut of the patch-type cantilever beam compound bending vibration working mode is composed of a nut matrix in the cantilever beam state and a plurality of other exciting telescopic pieces;

The nut base in the cantilever beam state adopts the cantilever beam restraint method, and the nut base in the cantilever beam state has a T-shaped design structure, and its T-shaped large-diameter end adopts the cantilever beam restraint method and is processed with several positioning holes for installation and fixing; the cantilever An internal thread is provided on the inner circular surface of the nut base body in the beam state, and a screw is rotatably connected to the internal thread of the nut base body in the cantilever beam state, and the thread lead angle of the internal thread is smaller than the equivalent friction angle between the internal thread and the threaded pair of the screw rod connection; On the outer circular surface of the nut base body in the cantilever beam state, there are a plurality of planes opposite to each other around the circumferential direction, and each plane is provided with a piece of other exciting type telescopic sheet, and each piece of other exciting type telescopic sheet All planes are connected to the plane; the expansion and contraction direction of the other-excited telescopic sheet is parallel to the axis of the nut base in the cantilever beam state; the other-excitation frequency of the other-excited telescopic sheet is in the ultrasonic frequency range; multiple sheets of other-excited telescopic The other exciting driving mode of the sheet is the traveling wave excitation mode or the standing wave excitation mode; the traveling wave excitation mode is that the driving phase difference of each two opposite planes is 180 degrees, and each The other excited telescopic sheets on two opposite planes are sequentially driven in a circumferentially adjacent manner, and the driving phase difference of the other excited telescopic sheets on the adjacent circumferential planes is 90 degrees; the standing wave excitation mode is each or several It can be driven individually or in groups, and the driving phase difference of each or each group of other excited expansion plates can be 0 degrees.

The present invention can change the self-locking working state of the nut base body to the unlocking working state when its exciting expansion plate inputs its driving signal, that is, the friction coefficient between thread pairs is greatly reduced, and the friction between the nut base body and the screw rod can be greatly reduced. The self-locking working state disappears. The invention also has the advantages of simple structure, low manufacturing cost and wide application range, and can be used for on-off, positioning and speed control in mechanical transmission systems, expanding the application fields of threaded auxiliary fasteners and transmission parts.

Description of drawings

Fig. 1 is the structure schematic diagram after screw rod 1-4 is rotatably connected in the unlockable nut of patch type cantilever beam compound bending vibration working mode of the present invention;

Fig. 2 is a schematic diagram of the cross-sectional structure along A-A in Fig. 1 .

Detailed ways

Specific embodiment 1: Referring to Fig. 1 and Fig. 2 for illustration, this specific embodiment is composed of a nut matrix 1 in a cantilever beam state and a plurality of other-excited telescopic sheets 2;

The nut base 1 in the cantilever beam state adopts the cantilever beam restraint method, and the nut base 1 in the cantilever beam state has a T-shaped design structure, and its T-shaped large-diameter end adopts the cantilever beam restraint mode and is processed with several positioning holes for installation and fixing. 1-2; the inner surface of the nut base 1 in the cantilever beam state is provided with an internal thread 1-3, and the internal thread 1-3 of the nut base 1 in the cantilever beam state is rotatably connected with a screw 1-4, and the internal thread 1- The thread lead angle of 3 is smaller than the equivalent friction angle between the internal thread 1-3 and the screw 1-4 connecting thread pair; on the outer circular surface of the nut base 1 in the cantilever beam state, there are a plurality of pairs of relative Plane 1-1, each plane 1-1 is provided with a piece of other exciting type telescopic sheet 2, and a plane of each other exciting type telescopic sheet 2 is connected with the plane 1-1; The expansion and contraction direction of the piece 2 is parallel to the axis of the nut base 1 in the state of the cantilever beam; the other excitation frequency of the other excitation type expansion piece 2 is in the ultrasonic frequency band; the other excitation driving mode of the multi-piece other excitation type expansion piece 2 is traveling wave Excitation working mode or standing wave exciting working mode; the traveling wave exciting working mode is that the driving phase difference of the other exciting telescopic sheet 2 on every two relative planes 1-1 is 180 degrees, and every two relative planes 1-1 -1 on the other excitation type telescopic sheet 2 is driven sequentially with the circumference adjacent, and the driving phase difference of the other excitation type expansion sheet 2 on the circumferential adjacent plane 1-1 is 90 degrees; the standing wave excitation mode is each Or several other excited type telescopic sheets 2 can be driven individually or in groups, and the driving phase difference of each or each group of other excited type elastic sheets 2 can be 0 degree.

Specific embodiment 2: Referring to Fig. 1 and Fig. 2 for illustration, the difference between this embodiment and specific embodiment 1 is that the other exciting type telescopic sheet 2 is a piezoelectric telescopic sheet, and its driving frequency is the same as that of the nut matrix in the state of the cantilever beam. The resonant frequency of 1 is consistent or similar, so that the nut base 1 in the state of the cantilever beam is excited to be in the state of ultrasonic vibration; the driving electrical signal waveform of the piezoelectric stretchable sheet can be a sine wave AC signal, a square wave AC signal, or a triangular wave AC signal. Electric signal or sawtooth alternating current signal. Other compositions and connections are the same as in the first embodiment.

Specific embodiment 3: Referring to Fig. 1 and Fig. 2 for illustration, the difference between this embodiment and the specific embodiment 1 is that the other exciting stretchable sheet 2 is a magnetostrictive sheet, a photostrictive sheet or a thermostrictive sheet. Other compositions and connections are the same as in the first embodiment.

Specific embodiment four: Referring to Fig. 1 and Fig. 2 for description, the difference between this embodiment and specific embodiment one is that the internal thread 1-3 of the nut matrix 1 in the state of the cantilever beam and the external thread of the screw rod 1-4 can be It is trapezoidal thread, triangular thread, rectangular thread, zigzag thread, pipe thread or non-standard thread. Other compositions and connections are the same as in the first embodiment.

Working principle: The unlockable nut in the compound bending vibration working mode of patch type cantilever beam mainly excites the unlockable nut to be in a high-frequency (generally greater than 1000 Hz) micro-vibration state through its exciting telescopic sheet. The generated anti-friction effect reduces the friction coefficient between the unlockable nut and the screw rod, and destroys the self-locking condition between the thread pairs, so that the unlockable nut is in the unlocking working state. The ultrasonic anti-friction effect caused by the micro-amplitude vibration in the ultrasonic frequency (generally greater than 13 kHz) is one of the anti-friction effects of high-frequency vibration. The application of vibration makes one or both of the contact surfaces in the state of ultrasonic vibration, which leads to the reduction of the friction coefficient between the contact surfaces. At present, this phenomenon has been confirmed by a large number of experimental studies. The principle of the friction effect works. At the same time, through the way of vibration coupling, motion traveling waves are superimposed on the surface of the thread pair between the unlockable nut and the screw, and the motion traveling waves can further provide relative motion or movement trend for the unlockable nut and screw, so the unlockable can be better realized The conversion and control of the two working states of self-locking and unlocking of the nut.

The unlockable nut of the patch cantilever beam compound bending vibration working mode mainly utilizes the mth order (m is a positive integer) along the axis direction and the nth order (n is a positive integer greater than 1) of the unlockable nut along the circumferential direction. The CB(m,n) compound bending vibration mode works. When the unlockable nut is in the CB(m, n) compound bending vibration mode, it shows that there are n pairs of bending vibration deformations in the axial direction of m order satisfying the spatial orthogonal relationship along the circumferential direction. There are n contact busbars parallel to the axis between the unlocking nut and the screw rod, which improves the bearing capacity of the unlockable nut and the stability of motion control.

Claims (4)

1. The unlockable nut of patch type cantilever beam compound bending vibration working mode is characterized in that it is composed of a nut base (1) in the state of cantilever beam and a plurality of other excited telescopic pieces (2); The nut base (1) in the cantilever beam state adopts the cantilever beam restraint method, and the nut base (1) in the cantilever beam state is a T-shaped design structure, and its T-shaped large-diameter end adopts the cantilever beam restraint method and several pieces are processed for installation and fixing. The positioning hole (1-2) used; the internal thread (1-3) is arranged on the inner circle surface of the nut base (1) in the cantilever beam state, and the internal thread (1-3) of the nut base (1) in the cantilever beam state ) is connected with a screw (1-4) in rotation, and the thread rise angle of the internal thread (1-3) is smaller than the equivalent friction angle between the internal thread (1-3) and the threaded pair of the screw (1-4); in the cantilever beam On the outer surface of the nut base (1) in the state, there are a plurality of planes (1-1) opposite to each other around the circumferential direction, and each plane (1-1) is provided with a piece of other exciting type telescopic sheet ( 2), and connect one plane of each other exciting telescopic sheet (2) to the plane (1-1); ) are parallel to the axes; the excitation frequency of the other-excited telescopic sheet (2) is within the ultrasonic frequency band; vibration working mode; the traveling wave excitation working mode is that the drive phase difference of the other excited telescopic sheet (2) on every two relative planes (1-1) is 180 degrees, and every two relative planes (1-1) The excitable telescopic sheet (2) on the other side is driven sequentially in the adjacent circle, and the driving phase difference of the other excited telescopic sheet (2) on the adjacent circumferential plane (1-1) is 90 degrees; the standing wave excitation works The mode is that each or several other-excited telescopic sheets (2) can be driven individually or in groups, and the driving phase difference of each or each group of other-excited telescopic sheets (2) can be 0 degrees. 2. The unlockable nut of patch-type cantilever beam compound bending vibration working mode according to claim 1, characterized in that the other exciting type expansion piece (2) is a piezoelectric expansion piece, and its driving frequency is related to the state of the cantilever beam. The resonant frequency of the nut matrix (1) is consistent or similar, so that the nut matrix (1) in the state of the cantilever beam is excited to be in the state of ultrasonic vibration; the driving electric signal waveform of the piezoelectric stretchable film can be a sinusoidal alternating current signal, a square wave AC signal, triangular AC signal, or sawtooth AC signal. 3. The unlockable nut of the chip-type cantilever beam compound bending vibration working mode according to claim 1, characterized in that the other excited stretchable sheet (2) is a magnetostrictive sheet, a photostrictive sheet or a thermostrictive sheet Telescoping sheet. 4. The unlockable nut of patch-type cantilever beam compound bending vibration working mode according to claim 1, characterized in that the internal thread (1-3) and the screw (1) of the nut base (1) in the state of the cantilever beam -4) The external thread can be trapezoidal thread, triangular thread, rectangular thread, zigzag thread, pipe thread or non-standard thread.

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