CN111107211A

CN111107211A - Clamping device

Info

Publication number: CN111107211A
Application number: CN201811260549.9A
Authority: CN
Inventors: 林德利; 潘龙
Original assignee: Shenzhen Ranvoo Technology Co Ltd
Current assignee: Shenzhen Ranvoo Technology Co Ltd
Priority date: 2018-10-26
Filing date: 2018-10-26
Publication date: 2020-05-05
Also published as: WO2020082444A1

Abstract

The invention provides a clamping device, which comprises a first clamping piece and a second clamping piece which are oppositely arranged, an elastic piece, a pull rod, an adjusting piece and a switch piece, wherein two ends of the elastic piece are respectively connected to the first clamping piece and the second clamping piece; the first clamping piece is arranged above the second clamping piece, a clamping gap is formed between the first clamping piece and the second clamping piece, and the first clamping piece and the second clamping piece are respectively provided with a first through hole and a second through hole; the pull rod is provided with a first end and a second end which are opposite, the first end is pivoted with the adjusting piece after penetrating through the first through hole, and the second end is pivoted with the switch piece after penetrating through the second through hole; the adjusting member is switchable between a first position and a second position by rotating about the pivot shaft, and the switch member is switchable between an open position and a closed position by rotating about the pivot shaft.

Description

Clamping device

Technical Field

The invention relates to the technical field of mobile phone accessories, in particular to a clamping device.

Background

With the rapid popularization of intelligent terminal devices, mobile phones have become essential electronic devices for people's daily life. In the driving process, a driver directly uses the mobile phone which is very dangerous, and at the moment, the mobile phone clamping support is needed to assist in fixing the mobile phone. The existing clamping support is usually fixed on a grid of an automobile air outlet by using clamping devices such as clamps, the existing clamps usually comprise two clamping arms and driving lever structures for driving the two clamping arms to be closed, the driving lever structures are usually arranged outside a shell of the clamps due to large volume, the whole volume of the clamps is large and attractive, the operation experience is reduced if the volume of the driving lever structures is reduced, and the user requirements cannot be met.

Disclosure of Invention

In view of the above, the present invention provides a clamping device, which not only can reduce the overall size of the clamping device, but also can make the clamping device more easy to use and beautiful.

In order to achieve the purpose, the invention adopts the following technical scheme:

a clamping device comprises a first clamping piece and a second clamping piece which are parallel to each other, an elastic piece connected between the first clamping piece and the second clamping piece, a pull rod penetrating through the first clamping piece and the second clamping piece, and an adjusting piece and a switch piece which are respectively pivoted at two ends of the pull rod; the first clamping piece is arranged above the second clamping piece, a clamping gap is formed between the first clamping piece and the second clamping piece, the first clamping piece and the second clamping piece are respectively provided with a first through hole and a second through hole, the first through hole vertically penetrates through the first clamping piece, the second through hole vertically penetrates through the second clamping piece, and the first through hole and the second through hole share a central axis; the pull rod is provided with a first end and a second end which are opposite, the first end is pivoted with the adjusting piece after penetrating through the first through hole, and the second end is pivoted with the switch piece after penetrating through the second through hole; the adjusting piece rotates around a pivot shaft and can be switched between a first gear and a second gear, and the switch piece rotates around the pivot shaft and can be switched between an opening position and a closing position; when the adjusting piece is in the first gear, the width of the clamping gap is larger than that of the adjusting piece in the second gear; when the switch piece rotates to the opening position, the first clamping piece and the second clamping piece are far away from each other under the action of the elastic force of the elastic piece until the clamping gap reaches the maximum width of the current gear; when the switch piece rotates to the closing position, the switch piece enables the first clamping piece and the second clamping piece to be close to each other and compress the elastic piece by lifting the pull rod until the clamping gap reaches the minimum width of the current gear.

Compared with the prior art, the invention has the following beneficial effects:

according to the clamping device, the pull rod penetrates through the first clamping piece and the second clamping piece, and the adjusting piece and the switch piece are respectively arranged at the two ends of the pull rod, so that a user can simply and conveniently install or dismantle the clamping device, the clamping force of the clamping device can be quickly adjusted according to actual use requirements, and the use scene is wide; meanwhile, as the first body of the first clamping piece and the second body of the second clamping piece are respectively provided with the accommodating grooves for accommodating the adjusting piece and the switch piece, the outer surface shape of the switch handle of the switch piece is matched with the peripheral wall of the second body, so that the peripheral wall of the first body and the peripheral wall of the second body form a regular shape structure on the whole, and the whole volume of the clamping device is reduced and the appearance is attractive.

Drawings

Fig. 1 is a schematic structural view of a clamping state of the clamping device of the invention in a second shift position.

Fig. 2 is a schematic structural view of the opened state of the clamping device in fig. 1.

Fig. 3 is a schematic structural view of an open state of the clamping device in fig. 1 in the first shift position.

Fig. 4 is a schematic sectional view of the holding device of fig. 1 taken along the direction a-a.

Fig. 5 is a schematic cross-sectional view of the clamping device of fig. 1 taken along the direction B-B.

Fig. 6 is a schematic view of the clamping device of fig. 1 in a disassembled structure.

Fig. 7 is a schematic view of the first clamping member of fig. 6 at another angle.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be further described with reference to the accompanying drawings.

Fig. 1 is a schematic view showing a clamping state of a clamping device of the present invention in a second shift position, fig. 2 is a schematic view showing an open state of the clamping device of fig. 1, fig. 3 is a schematic view showing an open state of the clamping device of fig. 1 in a first shift position, fig. 4 is a schematic view showing a cross-section of the clamping device of fig. 1 taken along a direction a-a, fig. 5 is a schematic view showing a cross-section of the clamping device of fig. 1 taken along a direction B-B, fig. 6 is a schematic view showing a disassembled structure of the clamping device of fig. 1, and fig. 7 is a schematic view showing a structure of the first clamping member of fig. 6 taken at.

Referring to fig. 1 to 3, the clamping device 100 of the present invention is used for connecting with a mobile phone holder or other product to fix the mobile phone holder to a specific position (such as an air outlet of an air conditioner of an automobile), and includes a first clamping member 1 and a second clamping member 2 disposed opposite to each other, an elastic member 6 having two ends respectively abutting against the first clamping member 1 and the second clamping member 2, a pull rod 3 penetrating through the first clamping member 1 and the second clamping member 2, and an adjusting member 4 and a switch member 5 pivotally connected to two ends of the pull rod 3, wherein the adjusting member 4 rotates around the pull rod 3 to adjust a distance between the first clamping member 1 and the second clamping member 2 so as to adjust a clamping force of the clamping device 100, and the switch member 5 rotates around the pull rod 3 to rapidly switch between a clamping state and an opening state.

Referring to fig. 4 to 7, the first clamping member 1 and the second clamping member 2 are parallel to each other as a whole, the first clamping member 1 is disposed above the second clamping member 2, and a clamping gap 1001 is formed therebetween. Specifically, the first clamping member 1 includes a first body 10 and a first clamping arm 12 extending outward from a front end surface 104 of the first body 10, the second clamping member 2 includes a second body 20 and a second clamping arm 22 extending outward from a front end surface 204 of the second body 20, the extending directions of the first clamping arm 12 and the second clamping arm 22 are parallel to each other, and the clamping gap 1001 is formed therebetween; the lower surface of the first clamping arm 12 and the upper surface of the second clamping arm 22 are respectively provided with

cushions

121 and 221, so as to prevent the clamping device 100 from scraping the object to be fixed during clamping. First holder 1 and second holder 2 are equipped with first through-hole 11 and second through-hole 21 respectively, and first through-hole 11 sets up on first body 10 and runs through first holder 1 perpendicularly, and second through-hole 21 sets up on second body 20 and runs through second holder 2 perpendicularly, and both share the axis in first through-hole 11 and second through-hole 21, can follow axis relative slip between them when making pull rod 3 wear to establish in first through-hole 11 and second through-hole 21.

The lower surface 103 of the first body 10 is provided with a limiting wall 16, the limiting wall 16 extends outwards along a direction parallel to the central axis of the first through hole 11, the upper surface 202 of the second body 20 is provided with a first inserting hole 26 corresponding to the limiting wall 16, and the limiting wall 16 is slidably inserted into the first inserting hole 26. In other embodiments, the positions of the limiting wall 16 and the first inserting hole 26 may be reversed, that is, the upper surface 202 of the second body 20 is provided with the limiting wall 16, the limiting wall 16 extends outwards along a direction parallel to the central axis of the second through hole 21, the lower surface 103 of the first body 10 is provided with the first inserting hole 26 corresponding to the limiting wall 16, and the limiting wall 16 is slidably inserted into the first inserting hole 26. The first clamping member 1 and the second clamping member 2 can be prevented from rotating relatively around the pull rod 3 by the limiting wall 16 matching with the first inserting hole 26, so that the stability of the clamping device 100 in use is improved.

The upper surface 202 of the second body 20 is provided with a blocking wall 27, the outward extending direction of the blocking wall 27 is perpendicular to the extending direction of the second clamping arm 22, the first body 10 is provided with a second inserting hole 17 corresponding to the blocking wall 27, and the blocking wall 27 is slidably inserted into the second inserting hole 17. In other embodiments, the positions of the blocking wall 27 and the second insertion hole 17 can be reversed, that is, the first body 10 is provided with the blocking wall 27, the outward extending direction of the blocking wall 27 is perpendicular to the extending direction of the first clamping arm 12, the second body 20 is provided with the second insertion hole 17 corresponding to the blocking wall 27, and the blocking wall 27 is slidably inserted into the second insertion hole 17. Through the matching of the blocking wall 27 and the second inserting hole 17, not only can the external object be blocked in the clamping gap 1001, the external object is prevented from interfering the relative movement between the first clamping piece 1 and the second clamping piece 2, but also the first clamping piece 1 and the second clamping piece 2 can be prevented from rotating relatively around the pull rod 3.

The rear end face of the first body 10 or the second body 20 extends outwards to form a connecting portion 28, preferably, the connecting portion 28 is disposed on the rear end face of the second body 20, the connecting portion 28 is used for being connected with a mobile phone holder and other products, so as to fix the mobile phone holder to a specific position (such as an air outlet of an automobile air conditioner), and the connecting portion 28 is preferably of a universal ball structure.

Referring to fig. 6, the pull rod 3 is an elongated shape and has a first end 31 and a second end 32 opposite to each other, the first end 31 passes through the first through hole 11, the second end 32 passes through the second through hole 21, the adjusting member 4 is pivotally connected to the first end 31, and the switch member 5 is pivotally connected to the second end 32, wherein the first end 31 and the adjusting member 4 are pivotally connected through the first rotating shaft 7, and the second end 32 and the switch member 5 are pivotally connected through the second rotating shaft 8. Specifically, the first end 31 and the second end 32 are respectively provided with a first shaft hole 311 and a second shaft hole 321, central axes of the first shaft hole 311 and the second shaft hole 321 are perpendicular to a central axis of the pull rod 3, the first rotating shaft 7 is simultaneously inserted into the first shaft hole 311 and the adjusting member 4, and the second rotating shaft 8 is simultaneously inserted into the second shaft hole 321 and the switch member 5, it should be understood that the first rotating shaft 7 can be fixedly connected to the first end 31 or the adjusting member 4, and the second rotating shaft 8 can be fixedly connected to the second end 32 or the switch member 5, which is not limited herein.

Referring to fig. 4 to 6, the adjusting member 4 has two opposite ends, one end of the adjusting member 4 is provided with a first pivot arm 41, the first pivot arm 41 extends outward along the length direction of the adjusting member 4, and the other end of the adjusting member 4 extends outward along the length direction thereof with an adjusting handle 42. The upper surface and the lower surface of the first pivoting arm 41 are respectively provided with a first contact surface 411 and a second contact surface 412, the sidewall of the first pivoting arm 41 is provided with a first via hole 413, the first contact surface 411 and the second contact surface 412 are parallel to each other, and the central axis of the first via hole 413 is parallel to the first contact surface 411 or the second contact surface 412. The first shaft 7 is simultaneously inserted into the first shaft hole 311 and the first through hole 413 to pivot the first end 31 and the adjusting member 4. In order to enable the pull rod 3 and the adjusting member 4 to be pivoted stably, the adjusting member 4 may be symmetrically provided with two first pivot arms 41, and the first end 31 is pivoted between the two first pivot arms 41 through the first rotating shaft 7.

When the first contact surface 411 abuts against the upper surface of the first clamping member 1, the adjusting member 4 is in the first gear 401, and when the second contact surface 412 abuts against the upper surface of the first clamping member 1, the adjusting member 4 is in the second gear 402, and the adjusting member 4 can be switched between the first gear 401 and the second gear 402 by rotating around the pivot shaft, for example, when the adjusting member 4 is in the first gear 401, the adjusting handle 42 is pulled to drive the first pivot arm 41 to rotate 180 degrees around the axis of the first pivot shaft 7, so that the first contact surface 411 is far away from the upper surface of the first clamping member 1, and the second contact surface 412 abuts against the upper surface of the first clamping member 1, so that the adjusting member 4 can be switched to the second gear 402, and the axis of the first pivot shaft 7, namely the pivot shaft of the adjusting member 4 and the pull rod 3. The vertical distance from the axis of the first rotating shaft 7 to the first contact surface 411 is smaller than the vertical distance from the axis of the first rotating shaft 7 to the second contact surface 412, so that the length of the pull rod 3 extending out of the first through hole 11 in the first gear position 401 is smaller than the length of the pull rod 3 extending out of the first through hole 11 in the second gear position 402, and therefore, when the adjusting member 4 is in the first gear position 401, the width of the clamping gap 1001 is larger than the width of the clamping gap 1001 of the adjusting member 4 in the second gear position 402. The width of the clamping gap 1001 can be quickly adjusted by toggling the adjusting member 4, so that the clamping device 100 can clamp objects with various thicknesses.

The switch member 5 has two opposite ends, one end of the switch member 5 is provided with a second pivoting arm 51, the second pivoting arm 51 extends outwards along the length direction of the switch member 5, the other end of the switch member 5 is bent upwards and extends perpendicular to the length direction to form a switch handle 52, and the tail end of the switch handle 52 departing from the second pivoting arm 51, namely the free end of the switch member 5. The end surface and the upper surface of the second pivot arm 51 are respectively provided with a third contact surface 511 and a fourth contact surface 512, the third contact surface 511 and the fourth contact surface 512 are vertically connected, the side wall of the second pivot arm 51 is provided with a second through hole 513, and the central axis of the second through hole 513 is parallel to the third contact surface 511 or the fourth contact surface 512. The second end 32 is simultaneously inserted into the second shaft hole 321 and the second through hole 513 through the second shaft 8, so that the second end 32 is pivotally connected to the switch 5. In order to enable the pull rod 3 and the switch member 5 to be pivoted stably, the switch member 5 may be symmetrically provided with two second pivot arms 51, and the second end 32 is pivoted between the two second pivot arms 51 through the second rotating shaft 8.

When the third contact surface 511 abuts against the lower surface of the second clamping member 2, the switch member 5 is in the open position 501, and when the fourth contact surface 512 abuts against the lower surface of the second clamping member 2, the switch member 5 is in the closed position 502, and the switch member 5 can be switched between the open position 501 and the closed position 502 by rotating around the pivot axis, for example, when the switch member 5 is in the open position 501, the switch handle 52 is toggled to drive the second pivot arm 51 to rotate 90 degrees around the axis of the second rotating shaft 8, so that the third contact surface 511 is far away from the lower surface of the second clamping member 2, and the fourth contact surface 512 abuts against the lower surface of the second clamping member 2, so that the switch member 5 can be switched to the closed position 502, and the axis of the second rotating shaft 8, namely, the pivot axis of the switch member 5 and the pull rod 3. The vertical distance from the axis of the second rotating shaft 8 to the third contact surface 511 is smaller than the vertical distance from the axis of the second rotating shaft 8 to the fourth contact surface 512, so that the length of the pull rod 3 extending out of the second through hole 21 in the open position 501 is smaller than the length of the pull rod 3 extending out of the second through hole 21 in the closed position 502, therefore, when the switch 5 is in the open position 501, the clamping gap 1001 reaches the maximum width of the current gear, and at this time, the clamping device 100 is in the open state; when the shutter 5 is in the closed position 502, the clamping gap 1001 reaches the minimum width of the current gear position, at which time the clamping device 100 is in the clamped state. The clamping device 100 can be quickly opened or closed by toggling the switch member 5, and meanwhile, due to the fact that the distance from the free end of the switch member 5 to the pivot shaft is long, a user can easily toggle the switch handle 52 by applying small force to the switch handle 52 by utilizing the lever principle, and therefore the experience of the user when using the clamping device 100 is enhanced.

In this embodiment, the first body 10 and the second body 20 form a circular structure together, the top wall 101 of the first body 10 is recessed to form a first receiving groove 13, the first receiving groove 13 is communicated with the first through hole 11, and the first end 31 extends into the first receiving groove 13 and is pivoted with the adjusting member 4; the peripheral wall 102 of the first body 10 is recessed to form a second receiving groove 14, the peripheral wall 201 of the second body 20 is recessed to form a third receiving groove 23, the third receiving groove 23 is communicated with the second through hole 21, the second end 32 extends into the third receiving groove 23 and is pivotally connected to the switch 5, and when the switch 5 is at the closed position 502, the free end of the switch 5 is received in the second receiving groove 14. The first receiving groove 13 is formed in the top wall 101 of the first body 10 and extends along the length direction of the first clamping member 1, so that when the adjusting member 4 is in the first gear 401 or the second gear 402, the adjusting handle 42 can be completely received in the first receiving groove 13, thereby reducing the overall volume of the clamping device 100. It should be understood that the first receiving groove 13 may be formed on the top wall 101 of the first body 10 to extend along the circumferential direction of the first clamping member 1, and is not limited thereto. The peripheral wall 102 of the first body 10 is provided with a second accommodating groove 14 extending along the circumferential direction of the first clamping piece 1, the peripheral wall 201 of the second body 20 is provided with a third accommodating groove 23 extending along the circumferential direction of the second clamping piece 2, and the upper end of the third accommodating groove 23 is aligned with the lower end of the second accommodating groove 14; the outer surface shape of the switch handle 52 matches with the peripheral wall of the second body 10, when the switch member 5 is in the closed position, the switch handle 52 can be simultaneously received in the second receiving groove 14 and the third receiving groove 23, so that the peripheral wall of the first body 10 and the peripheral wall of the second body 20 form a circular structure as a whole, which not only further reduces the volume of the clamping device 100, but also makes the overall visual effect of the clamping device 100 more beautiful. It should be understood that the first body 10 and the second body 20 may also form other shaped configurations together, such as a square configuration, without limitation.

Referring to fig. 7, the elastic member 6 is preferably a spring, and the elastic member 6 is sleeved on the pull rod 3; a step 15 is arranged in the first through hole 11, one end of the elastic element 6 abuts against the step 15, and the other end of the elastic element 6 abuts against the upper surface 202 of the second body 20. In other embodiments, the step 15 may be disposed in the second through hole 21, one end of the elastic member 6 abuts on the lower surface 103 of the first body 10, and the other end of the elastic member 6 abuts on the step 15. Lower surface 103 of first body 10

When assembling the clamping device 100, first, the first end 31 is inserted through the first through hole 11, and the first rotating shaft 7 is inserted through the first shaft hole 311 and the first through hole 413 in sequence, and then the adjusting member 4 is installed in the first accommodating groove 13; secondly, the elastic part 6 is sleeved on the pull rod 3, the second end 32 is aligned to the second through hole 21, then the first clamping part 1 and the pull rod 3 are covered above the second clamping part 2 from top to bottom, and meanwhile, the limiting wall 16 is inserted into the first inserting hole 26, and the blocking wall 27 is inserted into the second inserting hole 27; finally, the second end 32 extends out of the second through hole 21 and sequentially penetrates through the second shaft hole 321 and the second through hole 513 via the second shaft 8, so that the switch 5 and the pull rod 3 are pivotally connected in the third accommodating groove 23.

When the clamping device is used, the switch handle 52 of the switch piece 5 is turned and separated from the second accommodating groove 14 and the third accommodating groove 23 by toggling, the first clamping arm 11 and the second clamping arm 21 are mutually separated under the elastic action of the elastic piece 6, when the third contact surface 511 is abutted to the lower surface of the second clamping piece 2, the switch piece 5 moves to the opening position 501, at this time, the clamping gap 1001 reaches the maximum width of the current gear, and the clamping device 100 is switched to the opening state; after the object to be fixed is inserted into the clamping gap 1001, the switch handle 52 is rotated in the reverse direction to be accommodated in the second accommodating groove 14 and the third accommodating groove 23 again, at this time, the elastic member 6 is compressed, when the fourth contact surface 512 abuts against the lower surface of the second clamping member 2, the clamping gap 1001 reaches the minimum width of the current gear, the clamping device 100 is switched to the clamping state, and the elastic force of the elastic member 6 keeps the switch member 5 at the closing position 502.

When the adjusting member 4 is in the first position 401 and the user needs to provide a larger clamping force by the clamping device 100, the switch member 5 can be firstly shifted to the open position 501, and then the adjusting handle 42 is shifted to rotate so that the first contact surface 411 is far away from the upper surface of the first clamping member 1, at this time, the adjusting member 4 can extrude the first clamping member 1 to move towards the second clamping member 2 and compress the elastic member 6; when the adjustment handle 42 is rotated to abut the second contact surface 412 against the upper surface of the first clamping member 1, the first clamping member 1 moves away from the second clamping member 2 under the elastic force of the elastic member 6, thereby holding the adjustment member 4 in the second gear 402. When the user needs a smaller clamping force, the user only needs to dial the adjusting member 4 back to the first gear 401.

According to the clamping device 100, the pull rod 3 penetrates through the first clamping piece 1 and the second clamping piece 2, the adjusting piece 4 and the switch piece 5 are respectively arranged at the two ends of the pull rod 3, so that a user can simply and conveniently install or remove the clamping device 100, the clamping force of the clamping device 100 can be quickly adjusted according to actual use requirements, and the use scene is wide; meanwhile, as the first body 10 of the first clamping piece 1 and the second body 20 of the second clamping piece 2 are respectively provided with the accommodating grooves for accommodating the adjusting piece 4 and the switch piece 5, the outer surface shape of the switch handle 52 of the switch piece 5 is matched with the peripheral wall of the second body 10, so that the peripheral wall of the first body 10 and the peripheral wall of the second body 20 form a regular shape structure on the whole, and the whole volume of the clamping device 100 is reduced and the appearance is attractive.

The present invention is not limited to the specific details of the above-described embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention. The various features described in the foregoing detailed description may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

Claims

1. A clamping device is characterized by comprising a first clamping piece, a second clamping piece, a pull rod, an adjusting piece, a switch piece and an elastic piece, wherein the first clamping piece and the second clamping piece are oppositely arranged, and two ends of the elastic piece are respectively abutted against the first clamping piece and the second clamping piece;

the first clamping piece is arranged above the second clamping piece, a clamping gap is formed between the first clamping piece and the second clamping piece, the first clamping piece and the second clamping piece are respectively provided with a first through hole and a second through hole, the first through hole vertically penetrates through the first clamping piece, the second through hole vertically penetrates through the second clamping piece, and the first through hole and the second through hole share a central axis;

the pull rod is provided with a first end and a second end which are opposite, the first end penetrates through the first through hole, and the second end penetrates through the second through hole; the adjusting piece is pivoted with the first end and can be switched between a first gear and a second gear when rotating around a pivot shaft; the switch piece is pivoted with the second end and can be switched between an opening position and a closing position when rotating around a pivot shaft;

when the adjusting piece is in the first gear, the width of the clamping gap is larger than that of the adjusting piece in the second gear;

when the switch piece rotates to the opening position, the first clamping piece and the second clamping piece are far away from each other under the action of the elastic force of the elastic piece until the clamping gap reaches the maximum width of the current gear; when the switch piece rotates to the closing position, the switch piece enables the first clamping piece and the second clamping piece to be close to each other and compress the elastic piece by lifting the pull rod until the clamping gap reaches the minimum width of the current gear.

2. The clamping device of claim 1, wherein the adjustment member is provided at one end with a first pivot arm, an upper surface and a lower surface of the first pivot arm being provided with a first contact surface and a second contact surface, respectively, the first contact surface and the second contact surface being parallel to each other, the adjustment member being in the first gear position when the first contact surface abuts the upper surface of the first clamping member, and the adjustment member being in the second gear position when the second contact surface abuts the upper surface of the first clamping member.

3. The clamping device of claim 2, wherein said first pivot arm is pivotally connected to said first end by a first pivot shaft, the vertical distance from the axis of said first pivot shaft to said first contact surface being less than the vertical distance from the axis of said first pivot shaft to said second contact surface.

4. The clamping device of claim 2, wherein the switch member is provided at one end thereof with a second pivot arm, an end surface and an upper surface of the second pivot arm being provided with a third contact surface and a fourth contact surface, respectively, the third contact surface and the fourth contact surface being perpendicularly connected, the switch member being in the open position when the third contact surface abuts the lower surface of the second clamping member, and the switch member being in the closed position when the fourth contact surface abuts the lower surface of the second clamping member.

5. The clamping device of claim 4, wherein said second pivot arm is pivotally connected to said second end by a second pivot axis, the perpendicular distance from the axis of said second pivot axis to said third contact surface being less than the perpendicular distance from the axis of said second pivot axis to said fourth contact surface.

6. The clamping device as claimed in claim 4, wherein the first clamping member includes a first body and a first clamping arm extending from a front end surface of the first body, the first through hole is disposed on the first body, the second clamping member includes a second body and a second clamping arm extending from a front end surface of the second body, the second through hole is disposed on the second body, and the first clamping arm and the second clamping arm extend in parallel to each other with the clamping gap therebetween.

7. The clamping device as recited in claim 6, wherein the first body and the second body together form a circular or square configuration, a top wall of the first body is recessed to form a first receiving slot, the first receiving slot is in communication with the first through hole, and the first end extends into the first receiving slot and is pivotally connected to the adjustment member; the peripheral wall of the first body is concavely provided with a second containing groove, the peripheral wall of the second body is concavely provided with a third containing groove, the third containing groove is communicated with the second through hole, the second end extends into the third containing groove and is pivoted with the switch piece, and when the switch piece is in a closed position, the free end of the switch piece is contained in the second containing groove.

8. The clamping device of claim 6, wherein said resilient member is a spring and said resilient member is disposed over said pull rod; a step is arranged in the first through hole, one end of the elastic piece abuts against the step, and the other end of the elastic piece abuts against the upper surface of the second body; or a step is arranged in the second through hole, one end of the elastic piece abuts against the lower surface of the first body, and the other end of the elastic piece abuts against the step.

9. The clamping device as claimed in claim 6, wherein the lower surface of the first body is provided with a limiting wall, the limiting wall extends outwards along a direction parallel to the central axis of the first through hole, the upper surface of the second body is provided with a first inserting hole corresponding to the limiting wall, and the limiting wall is slidably inserted into the first inserting hole; or the upper surface of the second body is provided with a limiting wall, the limiting wall extends outwards along the direction parallel to the central axis of the second through hole, the lower surface of the first body is provided with a first inserting hole corresponding to the limiting wall, and the limiting wall can be slidably inserted into the first inserting hole.

10. The clamping device as claimed in claim 6, wherein the upper surface of the second body is provided with a blocking wall, the direction of the outward extension of the blocking wall is perpendicular to the extension direction of the second clamping arm, the first body is provided with a second inserting hole corresponding to the blocking wall, and the blocking wall is slidably inserted into the second inserting hole; or the first body is provided with a blocking wall, the outward extending direction of the blocking wall is perpendicular to the extending direction of the first clamping arm, the second body is provided with a second inserting hole corresponding to the blocking wall, and the blocking wall can be slidably inserted into the second inserting hole.