CN117489765A - Screw-nut mechanism, sliding table and clamping equipment - Google Patents

Abstract

The application discloses a screw-nut mechanism, a sliding table and clamping equipment, comprising a screw, a nut part and a rack part, wherein the nut part is in threaded connection with the screw and comprises a gear; wherein the rack portion includes a rack gear held in engagement with the gear and an elastic member connected to the rack gear, wherein the gear is capable of driving the rack gear by rotation to cause the rack gear to float with respect to the screw, and the elastic member is configured to resist the float of the rack gear to enable the nut portion to move axially along the screw. According to the technical scheme of this application, if meet the obstacle in the sliding part horizontal migration in-process, the lead screw is under the unchangeable circumstances of drive power, because sliding part is stopped, consequently partial drive power can convert into the torsion of gear rotation, makes the rack with gear engagement overcome current elasticity and produce and float to realized the buffering effect, reduced the risk of sliding part collision damage.

Description

Screw-nut mechanism, sliding table and clamping equipment

Technical Field

The application relates to the field of machining equipment, and more particularly relates to a screw nut mechanism, a sliding table and clamping equipment.

Background

Currently, devices such as servo slipways that convert rotational movement of a screw into linear movement of a sliding member are generally composed of a servo motor, a screw nut, and a sliding member such as a slipway. The servo motor can drive the screw rod to rotate, the screw rod nut is fixed on the sliding component, and when the screw rod rotates, the screw rod nut is limited by the sliding component and cannot rotate along with the screw rod, so that axial movement can be carried out along the screw rod, and the rotary movement of the screw rod driven by the servo motor is converted into accurate linear movement of the sliding component. In the prior art, the screw nut is fixedly connected with the sliding part, and if the servo motor cannot be stopped in time to continue driving when the sliding part encounters obstruction, the equipment or the workpiece can be possibly damaged.

Therefore, how to provide a buffer structure for an apparatus that converts rotational motion into linear motion is a technical problem that needs to be solved by the present application.

Disclosure of Invention

In view of the foregoing, the present application proposes a screw-nut mechanism to overcome the above technical problems.

According to the present application, a screw-nut mechanism is proposed, comprising a screw, a nut portion and a rack portion, wherein the nut portion is in threaded connection with the screw and the nut portion comprises a gear; wherein the rack portion includes a rack gear held in engagement with the gear and an elastic member connected to the rack gear, wherein the gear is capable of driving the rack gear by rotation to cause the rack gear to float with respect to the screw, and the elastic member is configured to resist the float of the rack gear to enable the nut portion to move axially along the screw.

Preferably, a detection unit to detect a floating amount of the rack is included.

According to the present application, there is also provided a slide table including the lead screw nut mechanism and the slide table portion as described above, the slide table portion being connected with the nut portion so as to be driven by the lead screw nut mechanism to move axially along the lead screw.

Preferably, the nut portion is rotatably connected to the slide portion through a mounting block, wherein the nut portion includes a nut fixedly connected to the gear, the nut has a thread matching the screw, and the mounting block has a through hole opened in an axial direction of the screw, at least a portion of the nut is capable of being inserted into the through hole and is rotatably restrained to the mounting block by a stopper structure, so that the slide portion is capable of being moved only in an axial direction of the screw.

Preferably, the rack portion is mounted to the slide table portion by a mounting member, the mounting member includes a cavity in which the rack is mounted, and the mounting member includes an opening portion capable of exposing at least a part of the rack, and the gear is capable of meshing with the rack through the opening portion.

Preferably, the elastic member includes a spring disposed in the cavity, wherein the spring is adjustably compressed between the rack and an end surface of the cavity by an adjustment mechanism to adjust an amount of compression of the spring.

According to the present application, there is also proposed a clamping device comprising: the two sliding tables are arranged oppositely along the extending direction of the screw rod; a clamp arm provided to the slide table section; and a driving unit driving the screw rod to rotate so as to make the two clamping arms approach to or separate from each other.

Preferably, the screw driving device comprises a first bevel gear mounted at the end of the screw and a second bevel gear meshed with the two first bevel gears, so that one screw can rotate reversely when the other screw is driven to rotate by the driving unit.

Preferably, the gripping apparatus includes a detection unit to detect a floating amount of the rack.

Preferably, the rack is provided with a blocking piece for detection by the detection unit, and the blocking piece can be switched between at least a first position corresponding to normal movement of the clamping arm and a second position corresponding to the clamping arm already holding the workpiece by the floating of the rack, and the detection unit comprises a first sensor and a second sensor, and the first sensor and the second sensor respectively correspond to the first position and the second position.

According to the technical scheme of this application, if meet the obstacle in the lead screw drive sliding part horizontal migration in-process, the lead screw is under the unchangeable circumstances of drive power, because sliding part is stopped, consequently partial drive power can convert into gear rotation's torsion, makes the rack overcome current elasticity and produces floatingly to realized the buffering effect, reduced sliding part collision damage's risk.

Additional features and advantages of the present application will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

FIG. 1 is a schematic cross-sectional view of a lead screw nut mechanism according to one embodiment of the present application;

FIG. 2 is a partial schematic view of a slip according to one embodiment of the present application;

FIG. 3 is a schematic view of the slide table shown in FIG. 2 at another angle;

fig. 4 is a schematic view of a clamping device according to an embodiment of the present application.

Detailed Description

The technical solutions of the present application will be described in detail below with reference to the accompanying drawings in combination with embodiments.

According to one aspect of the present application, there is provided a screw-nut mechanism comprising a screw 100, a nut portion and a rack portion, wherein the nut portion is threadedly connected with the screw 100 and the nut portion comprises a gear 111; wherein the rack portion includes a rack 112 held in engagement with the gear 111 and an elastic member connected to the rack 112, wherein the gear 111 is capable of rotationally driving the rack 112 to cause the rack 112 to float with respect to the screw 100, and the elastic member is configured to resist the float of the rack 112 to enable the nut portion to move axially along the screw 100.

According to the technical scheme of this application, nut portion can be connected with sliding part to drive sliding part along lead screw 100 axial displacement, if meet the obstacle in the lead screw 100 drive sliding part horizontal migration in-process, lead screw 100 is under the unchangeable circumstances of drive power, because sliding part is stopped, consequently partial drive power can be converted into gear 111 rotatory torsion, makes rack 112 overcome current elasticity and produce the unsteady, thereby has realized the buffering effect, has reduced the risk of sliding part collision damage.

In the technical solution of the present application, the rack portion may be mounted at a suitable position in different application environments, so that the rack 112 is meshed with the gear 111, and at the same time, the rack may only move linearly in a vertical direction relative to the nut portion and may move axially along with the screw rod along with the nut portion, for example, the rack portion and the nut portion may be mounted together on the sliding member; alternatively, the rack portion may be attached to a guide device such as a slide rail, and connected to the nut portion by a connector, and the like, and the rack portion is not limited thereto, as long as the rack 112 and the gear 111 can be held in engagement and can move together in the axial direction. The elastic member may take the form of, for example, a spring, a tension spring, or a cylinder, etc., and may be provided with a plurality of elastic members to provide resistance at both ends of the rack 112, respectively, so that the rack 112 can provide resistance regardless of whether the gear 111 is rotated forward or backward.

In the actual use process, the screw rod 100 rotates to drive the gear 111 to rotate, and the rack 112 meshed with the gear 111 is influenced by the torsion of the gear 111 to resist the resistance of the elastic piece to generate floating. With the increase of the floating amount, the resistance of the elastic member is also raised until the resistance of the elastic member and the torque force transferred to the rack 112 by the gear 111 reach balance, the rack 112 cannot further float, the gear 111 is stopped rotating, and the nut portion drives the rack portion to axially move along the screw rod 100. When the movement is blocked, the obstacle applies a force opposite to the movement direction to the nut part, so that the balance between the torsion force of the gear 111 and the resistance force of the elastic member is eliminated, the torsion force of the gear 111 is lifted to start rotating, the rack 112 further resists the elastic force of the elastic member to generate floating, and therefore a buffering effect is generated, and the damage caused by the stress collision of the nut part, the rack part or the follow-up sliding part and the obstacle is avoided.

In order to be able to find out in time that an obstacle or the like is encountered during the movement of the sliding member, according to a preferred embodiment, a detection unit is included for detecting the amount of float of the rack 112.

In the technical solution of the present application, the detection unit may take a suitable form, for example, a position sensor may be disposed on the rack 112, so as to obtain a floating amount by detecting a position change of the rack 112, or may take a form in which a light shielding member is disposed on the rack 112 and is matched with an optical sensor, and when the light shielding member floats along with the rack 112 to reach a specific position, the optical sensor may be shielded, so as to determine that the sliding member contacts an obstacle. The detection unit may be connected to a driving mechanism for driving the screw 100, so that the driving mechanism stops driving in time, or may be connected to other control devices, so that an operator selects other processing modes such as stopping the device or clearing obstacles according to actual situations.

According to another aspect of the present application, there is also provided a slide table including the lead screw nut mechanism as described above and a slide table portion 130, the slide table portion 130 being connected with the nut portion to be axially moved along the lead screw 100 by driving of the lead screw nut mechanism.

According to the technical scheme of this application, if meet the obstacle in the horizontal migration in-process of lead screw 100 drive slip table portion 130, lead screw 100 is under the unchangeable circumstances of drive power, because slip table portion 130 is stopped, consequently partial drive power can be converted into the rotatory torsion of gear 111, and the rotation of gear 111 makes rack 112 overcome current elasticity and produces floatingly to realized the buffering effect, reduced slip table portion collision damage's risk.

In the technical scheme of the application, slip table portion 130 can carry out axial displacement through the guide rail 201 guide that sets up with lead screw 100 in parallel, slip table portion 130 can be installed in guide rail 201 through sliding block 202 slidable, through the guide of guide rail 201, slip table portion 130 can only carry out axial displacement and unable rotation, thereby when slip table portion 130 is driven along axial displacement in-process by lead screw 100 if receive the barrier etc. to stop axial displacement, thereby make the drive of lead screw 100 turn into the rotation of nut portion, thereby make rack 112 resist the resistance of elastic component in order to realize the cushioning effect. In order to improve the structural strength of the slide table, a plurality of guide rails 201 may be provided, and a plurality of slide blocks 202 may be provided to the corresponding slide table section 130. The nut portion may take an appropriate form to be capable of winding the wire rod 100 and being connected to the slide table portion 130 so that the slide table portion 130 can be moved by the nut portion, for example, the nut portion may be attached to a bearing so that the nut portion can rotate with respect to the bearing, the bearing may be fixed to the slide table portion 130 by a bolt, welding, or the like, and the like, but is not limited thereto as long as the nut portion can be rotatably attached to the slide table portion 130. In addition, the rack portion may be mounted at an appropriate position of the slide table portion 130 by means of bolts, welding, or the like so as to keep the rack 112 engaged with the gear 111. In different application environments, the slide table portion 130 may be provided with different components, for example, a tray or the like may be provided at the slide table portion 130 to carry the workpiece when the slide table is used to move the workpiece, or a clamp arm may be provided at the slide table portion 130 and a plurality of slide tables may be provided to be used together in cooperation in the case of clamping the workpiece, or the like.

The nut part may take a suitable form to be coupled with the slip part 130, and according to a preferred embodiment, as shown in fig. 2, is rotatably coupled with the slip part 130 by a mounting block 113, wherein the nut part includes a nut 114 fixedly coupled with the gear 111, the nut 114 has a thread matching with the screw 100, and the mounting block 113 has a through hole opened in an axial direction of the screw 100, at least a portion of the nut 114 being capable of being inserted into the through hole and rotatably limiting the nut 114 to the mounting block 113 by a limiting structure such that the slip part 130 can be axially moved only with respect to the screw.

In the technical solution of the present application, the nut 114 may be connected to the gear 111 by means of a bolt, a pin or the like so as to be rotatable together with the gear 111 around the screw 100, and in addition, the gear 111 may be used only for meshing with the rack 112, and is screwed to the screw 100 by the nut 114. The mounting block 113 may be fixed to the slide table part 130, and the nut 114 may be provided in a through hole of the mounting block 113, and the nut 114 may be restrained in the through hole by a restraining structure, for example, the nut 114 may be provided with an annular flange protruding in its circumferential direction, the through hole of the mounting block 113 having an annular groove matching with the annular flange, thereby restraining, so that the nut 114 may be rotatably mounted in the mounting block 113, and a bearing matching with the nut 114 may be provided in the through hole, thereby reducing friction force of the nut 114 rotating in the through hole, and in addition, for convenience of mounting, the mounting block 113 may include two halves which may be opened and closed along a plane perpendicular to a rotation axis of the nut 114, respectively, including one part of the annular grooves, the two halves may be connected by bolts, thereby forming a complete annular groove to accommodate the annular flange, without limitation, so long as the nut 114 can be rotatably mounted to the slide table part 130 by the mounting block 113. In addition, the rack portion may be mounted in a suitable form so that the gear 111 is kept engaged with the gear 112, for example, the rack portion may be mounted at a suitable position of the slide table portion 130 by a connector vertically or at an angle with respect to the slide table portion 130, or the rack portion may be mounted to the mounting block 113 or the like as long as the rack 112 can be kept engaged with the gear 111, which is not limited.

The rack portion may be installed in various forms so that the rack 112 is kept engaged with the gear 111, and according to a preferred embodiment, as shown in fig. 2 and 3, the rack portion is installed to the slide portion 130 by a mounting member 120, the mounting member 120 includes a cavity 1201, the rack 112 is installed in the cavity 1201, and the mounting member 120 includes an opening portion capable of exposing at least a portion of the rack 112, and the gear 111 is capable of being engaged with the rack 112 through the opening portion.

In the technical scheme of the application, the mounting piece 120 can be connected with the sliding table portion 130 through the bolt, in order to be convenient for adjust the position, a plurality of screw holes can be seted up to the mounting piece 120 and/or sliding table portion 130 to thereby make the mounting piece 120 can be through the installation of different screw holes adjust the mounting piece for the position of sliding table portion 130, rack 112 and elastic component can set up in cavity 1201, so that rack 112 can float in cavity 1201 through the resistance of customer service elastic component. The mounting member 120 includes an opening portion so that at least a portion of the rack 112, in particular, the tooth portion 1121 of the rack 112 can be exposed out of the mounting member 120 through the opening portion and other portions of the rack 112 can be restrained by the cavity 1201 and held in the cavity 1201, preventing the rack 112 from being separated from the cavity 1201 during floating. A portion of the gear 111 can pass through the opening and engage with the rack 112, so that the rack 112 can be driven to float in the cavity 1201 against the resistance of the elastic member by rotation of the gear 111.

Wherein, the elastic member may be a spring, a tension spring, a cylinder, or the like, which can provide a member that enhances resistance with compression or extension, and may be connected to the rack 112 in a suitable form, for example, the elastic member may be connected to the bottom of the rack 112, and the rack 112 is maintained above the cavity 1201 in a normal state; two elastic members may be provided to be respectively connected to the top and bottom of the rack 112, in which case the rack 112 is held in the middle of the cavity 1201 in a normal state, and at this time, the elastic members can provide the rack 112 with resistance or the like regardless of the forward rotation or reverse rotation of the gear 111, and the present invention is not limited thereto as long as the rack 112 can be provided with resistance.

The elastic member may take a suitable form, and according to a preferred embodiment, as shown in fig. 1, the elastic member includes a spring 115 disposed in the cavity 1201, wherein the spring 115 is compressed between the rack 112 and an end surface of the cavity 1201 by an adjusting mechanism to adjust the compression amount of the spring 115.

In the technical scheme of this application, the elastic component adopts the form of spring 115 to set up between rack 112 and cavity 1201, in order to be convenient for rack 112 and spring 115 to be connected and realize the elasticity through adjustment mechanism adjustment spring 115, according to a preferred embodiment, as shown in fig. 1, rack 112 has through-hole 1122 that link up along its length direction, through-hole 1122 can be plugged through setting up adjusting part 118, and adjusting part 118 can adjust the degree of depth of stretching into through-hole 1122, spring 115 can stretch into in through-hole 1122 and by adjusting part 118 backstop, thereby through the compression volume of adjusting part 118's position adjustment spring 115, and then realize the cushioning effect of adjustment feed screw nut mechanism. The adjustment member 118 may be adjustably disposed in the through hole 1122 in a suitable form, for example, the through hole 1122 may include at least a portion thereof including a threaded section 1123, and the adjustment member 118 may be threadedly coupled to the threaded section 1123 such that the depth of penetration into the through hole 1122 may be adjusted by rotating the adjustment member 118. To facilitate rotation of the adjustment member 118, the mounting member 120 may be provided with an adjustment hole capable of exposing an end portion of the adjustment member 118 from the top through which an operator may operate the adjustment member 118.

According to another aspect of the present application, there is also provided a clamping device comprising: two sliding tables as described above, the two sliding tables are oppositely arranged along the extending direction of the screw rod 100; a clamp arm 200 provided to the slide table section 130; and a driving unit 300 driving the screw 100 to rotate so as to approach or separate the two clip arms 200 from each other.

According to the technical scheme of the application, the driving unit 300 drives the screw rod 100 to rotate, so that the clamp arm 200 is driven to horizontally move, and if an obstacle or a workpiece is encountered in the moving process of the clamp arm 200, under the condition that the driving force for driving the screw rod 100 to rotate by the driving unit 300 is unchanged, part of the driving force can be converted into the torsion for rotating the gear 111 because the clamp arm 200 is stopped by the obstacle or the workpiece, so that the rack 112 overcomes the current elasticity to generate floating, thereby realizing the buffering effect and reducing the risk of collision damage of the clamp arm.

In the technical scheme of this application, clamping device can include the mount, and two slip tables can be relative set up respectively in the both ends of mount to make the tip of two lead screws 100 be close each other, thereby make two slip table portions 130 can remove to clamping device's intermediate position in order to centre gripping work piece. The two sliding tables may be provided with driving units 300 respectively to drive the two screw rods 100 to rotate respectively, or may also be provided with two screw rods 100 having different screw thread directions, and dock the two screw rods 100, so that the two screw rods 100 can rotate together, and one driving unit 300 drives the two docked screw rods 100 to rotate in various manners, so long as the driving unit 300 can drive the clamping arms 200 to approach or separate from each other, so as to clamp the workpiece. In order to enable the clamping arm 200 to maintain the current clamping force after clamping the workpiece, the driving unit 300 may employ a servo motor having a self-locking function.

Through the application, when the clamping arm 200 clamps a workpiece and cannot continue to move, the driving force for driving the screw rod 100 to rotate by the driving unit 300 is converted into the torque force for driving the gear 111 to rotate, so that the rack 112 meshed with the gear 111 overcomes the resistance of the current elastic piece to generate floating, the driving force for driving the clamping arm 200 to continue to move is counteracted by the floating of the elastic piece, the buffering effect is achieved, and the clamping arm 200 is prevented from continuing to move to apply pressure to the workpiece, so that the workpiece or clamping equipment is damaged.

The two sliding tables may be connected in a suitable form to drive the two screw rods 100 to rotate by one driving unit 300, and according to a preferred embodiment, as shown in fig. 4, include a first bevel gear 101 mounted to an end of the screw rod 100 and a second bevel gear 102 engaged with the two first bevel gears 101 to enable the reverse rotation of the other screw rod 100 when one of the screw rods 100 is driven to rotate by the driving unit 300.

In the technical scheme of the application, the second bevel gear 102 can be arranged between the two first bevel gears 101 and meshed with the two first bevel gears 101, so that the two screw rods 100 are linked, and when one screw rod 100 rotates, the other screw rod 100 is driven to reversely rotate through the second bevel gear 102. Thus, the driving unit 300 can drive only one screw 100 to reversely rotate the other screw 100 at the same speed, so that the two reversely rotated screws 100 can drive the two clamping arms 200 to approach each other or to separate from each other, thereby clamping the workpiece.

In order to detect the operating state of the clamping arm 200, according to a preferred embodiment, the clamping device comprises a detection unit to detect the amount of float of the rack 112.

In the technical solution of the present application, the detection unit may take a suitable form, for example, a position sensor may be disposed on the rack 112, so as to obtain a floating amount by detecting a position change of the rack 112, or may take a form in which a light shielding member is disposed on the rack 112 and is matched with an optical sensor, and when the light shielding member floats along with the rack 112 to reach a specific position, the optical sensor may be shielded, so as to determine that the sliding member contacts an obstacle. The detection unit may be connected to the driving unit 300, so that when it is detected that the clamping arm encounters an obstacle, or when the workpiece is clamped, the driving unit 300 can be stopped in time to continue driving the screw rod 100 to rotate, or may be connected to other control devices, so that an operator selects other processing modes such as stopping the device or cleaning the obstacle according to actual situations.

The detection unit may take a suitable form to detect the operation state of the clamp arm 200, and according to a preferred embodiment, as shown in fig. 3, the rack 112 is mounted with a blocking piece 122 for detection by the detection unit, and by the floating of the rack 112, the blocking piece 122 is at least capable of being switched between a first position corresponding to the normal movement of the clamp arm 200 and a second position corresponding to the clamp arm 200 having held the workpiece, and the detection unit includes a first sensor 123 and a second sensor 124, the first sensor 123 and the second sensor 124 corresponding to the first position and the second position, respectively.

In the technical scheme of this application, detecting element can include first sensor 123 and second sensor 124, and first sensor 123 and second sensor 124 can set up in installed part 120 to along the setting of rack 112's floating direction interval, rack 112 can install separation blade 122, so that separation blade 122 can be along with the unsteady and removal of rack 112, thereby can remove to the position that first sensor 123 corresponds and the position that second sensor 124 corresponds. When the clamp arm 200 operates normally, the torsion of the gear 111 and the resistance of the elastic member received by the rack 112 reach balance, and at this time, the blocking piece 122 can float to a first position, where the first position can reflect that the clamp arm 200 is in normal operation, and the first sensor 123 is set to correspond to the first position, so as to detect that the clamp arm 200 is in normal operation; when the clamping arm 200 clamps a workpiece, the rack 112 is further floated due to the torsion of the gear 111, which is greater than the resistance provided by the elastic member, and when the clamping arm 200 clamps the workpiece, the stop 122 moves from the first position to the second position, and the second sensor 124 is set to correspond to the second position, so that it is detected that the clamping arm 200 clamps the workpiece. In order to be able to stop the driving unit 300 in time and continue driving the screw 100, the second sensor 124 may be connected to the driving unit 300 so that the driving unit 300 can be braked in time when the second sensor 124 detects the clamped state.

Through this application, can the current running state of visual demonstration arm lock 200 through detecting element to provide the buffering for arm lock 200 through the lead screw nut mechanism, reduced the risk that parts such as work piece or arm lock 200 collide the damage.

The preferred embodiments of the present application have been described in detail above, but the present application is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solutions of the present application within the scope of the technical concept of the present application, and all the simple modifications belong to the protection scope of the present application.

In addition, the specific features described in the foregoing embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations are not described in detail.

Moreover, any combination of the various embodiments of the present application may be made without departing from the spirit of the present application, which should also be considered as disclosed herein.

Claims (10)

1. A screw-nut mechanism characterized by comprising a screw (100), a nut portion and a rack portion, wherein the nut portion is in threaded connection with the screw (100) and the nut portion comprises a gear (111); wherein the rack portion includes a rack (112) held in engagement with the gear (111) and an elastic member connected to the rack (112), wherein the gear (111) is capable of rotationally driving the rack (112) to cause floating of the rack (112) with respect to the screw (100), and the elastic member is configured to resist floating of the rack (112) to enable axial movement of the nut portion along the screw (100).

2. The lead screw nut mechanism according to claim 1, characterized by comprising a detection unit to detect a floating amount of the rack (112).

3. A slide table characterized by comprising the lead screw nut mechanism as claimed in claim 1 and a slide table portion (130), the slide table portion (130) being connected to the nut portion to be driven by the lead screw nut mechanism to move axially along the lead screw (100).

4. A slip according to claim 3, wherein the nut portion is rotatably connected to the slip portion (130) by means of a mounting block (113), wherein the nut portion comprises a nut (114) fixedly connected to the gear (111), the nut (114) having a thread matching the screw (100), and the mounting block (113) having a through hole opening axially along the screw (100), at least a portion of the nut (114) being insertable into the through hole and being rotatably restrained to the mounting block (113) by a restraining structure such that the slip portion (130) is only axially movable relative to the screw.

5. The slide table according to claim 4, wherein the rack portion is mounted to the slide table portion (130) by a mounting member (120), the mounting member (120) includes a cavity (1201), the rack (112) is mounted in the cavity (1201), and the mounting member (120) includes an opening portion through which at least a portion of the rack (112) can be exposed, and the gear (111) can be engaged with the rack (112) through the opening portion.

6. The slide table according to claim 5, wherein the elastic member includes a spring (115) provided in the cavity (1201), wherein the spring (115) is adjustably compressed between the rack (112) and an end face of the cavity (1201) by an adjustment mechanism to adjust an amount of compression of the spring (115).

7. A clamping apparatus, comprising: -two sliding tables according to any one of claims 3 to 6, the two sliding tables being arranged opposite each other along the extension direction of the screw (100); a clamp arm (200) provided to the slide table section (130); and a driving unit (300) for driving the screw (100) to rotate so as to move the two clip arms (200) toward or away from each other.

8. Clamping device according to claim 7, characterized in that it comprises a first bevel gear (101) mounted to the end of the screw (100) and a second bevel gear (102) meshing with both first bevel gears (101) so that one of the screws (100) can rotate in opposite directions when the other screw (100) is driven in rotation by the driving unit (300).

9. Clamping device according to claim 7 or 8, characterized in that it comprises a detection unit to detect the floating amount of the rack (112).

10. Clamping device according to claim 9, characterized in that the rack (112) is fitted with a catch (122) for detection by the detection unit, which detection unit comprises a first sensor (123) and a second sensor (124), which first sensor (123) and second sensor (124) correspond to the first position and second position, respectively, by the floating of the rack (112), the catch (122) being at least switchable between a first position, corresponding to the normal movement of the clamping arm (200), and a second position, corresponding to the clamping arm (200) having gripped the workpiece.