CN221184761U - Double telescopic full-stroke chuck - Google Patents

Abstract

The utility model relates to the technical field of chucks, in particular to a double-telescopic full-stroke chuck, which comprises a disk seat, a jaw assembly and a power unit, wherein the jaw assembly comprises a jaw, a sliding seat and a stroke-increasing gear set, the jaw is slidably arranged on the sliding seat, the sliding seat is slidably arranged on the disk seat along the sliding direction between the jaw and the sliding seat, the stroke-increasing gear set comprises a stroke-increasing Cheng Chilun and a movable rack and a fixed rack which are respectively engaged with two sides of the stroke-increasing gear.

Description

Double telescopic full-stroke chuck

Technical Field

The utility model relates to the technical field of chucks, in particular to a double-telescopic full-stroke chuck.

Background

The full-stroke chuck is a workpiece which can work in a full stroke and is applicable to clamping range, is mainly matched with laser pipe cutting equipment, and can meet the key processing requirements of thin walls such as square pipes, round pipes, elliptical pipes and the like;

For example, the full-stroke hollow air chuck disclosed in publication No. CN111451536a, and specifically discloses that four groups of jaw assemblies are arranged at the front end of the chuck body, the driving assembly is suitable for driving the jaw assemblies to move, and the power of the driving assembly is meshed with the tooth groove on one side of the sliding block through the second gear so as to drive the jaws fixed on the sliding block to radially stretch, which obviously has the defect that the radial upward stroke of the jaws is completely determined by the length of the tooth groove on the side of the sliding block, resulting in larger space required by the sliding block in the radial direction of the chuck, which is not beneficial to the miniaturization design of the chuck.

Disclosure of utility model

The utility model aims to solve the technical problems that: in order to solve the problem that in the prior art, the radial upstroke of a jaw of a chuck is completely determined by the length of a tooth slot at the side of a sliding block, so that the sliding block is larger in radial required space of the chuck, the small-sized design of the chuck is not facilitated, and the double-telescopic full-stroke chuck is provided.

The technical scheme adopted for solving the technical problems is as follows: a dual telescopic full stroke chuck comprising:

A tray seat;

The clamping jaw assembly is provided with a plurality of clamping jaw assemblies, the clamping jaw assemblies are arranged around the center of the chuck, the clamping jaw assemblies comprise clamping jaws, sliding seats and a range-extending gear set, the clamping jaws are slidably arranged on the sliding seats, the sliding seats are slidably arranged on the tray seats along the sliding direction between the clamping jaws and the sliding seats, the range-extending gear set comprises a range-extending Cheng Chilun and a movable rack and a fixed rack which are respectively meshed with two sides of the range-extending gear, the range-extending Cheng Chilun is rotatably arranged on the sliding seats, the movable rack is fixed on the clamping jaws, and the fixed rack is fixed on the tray seats;

and the power unit is used for driving the sliding seat on the disc seat to slide.

Further, two jaw assemblies are first jaw assemblies, the jaws of the two first jaw assemblies are oppositely arranged in the first direction, and a sliding seat in the first jaw assemblies is slidably arranged on the tray seat along the first direction;

The two jaw assemblies are second jaw assemblies, the jaws of the two second jaw assemblies are oppositely arranged in the second direction, and the sliding seat in the second jaw assemblies is slidably arranged on the tray seat along the second direction;

The first direction and the second direction are intersected with each other.

Further, the power unit comprises a first power assembly and a second power assembly;

The first power assembly is used for driving the sliding seats of the two first claw assemblies to slide along a first direction;

the second power assembly is used for driving the sliding seat of the two second claw assemblies to slide along the second direction.

Further, the first power assembly comprises a first linkage ring and a first air cylinder, the first linkage ring is rotatably arranged on the tray seat, one end of the first air cylinder is hinged with the tray seat, and the other end of the first air cylinder is hinged with the first linkage ring;

The first linkage ring is provided with two first arc racks, the two first arc racks are respectively meshed with a first driving gear in rotary connection with the disc seat, a first transmission rack is fixed on a sliding seat of the first jaw assembly, the two first driving gears are in one-to-one correspondence with the first transmission racks of the two first jaw assemblies, and the first driving gears are in transmission connection with the first transmission racks corresponding to the first driving gears.

Further, a first intermediate gear is coaxially fixed on the first driving gear, the first intermediate gear is meshed with a first driven gear, and the first driven gear is meshed with a first transmission rack on the side where the first driven gear is located.

Further, the second power assembly comprises a second linkage ring and a second air cylinder, the second linkage ring is rotatably arranged on the tray seat, one end of the second air cylinder is hinged with the tray seat, and the other end of the second air cylinder is hinged with the second linkage ring;

The second driving gear is in one-to-one correspondence with the second driving racks of the two second jaw assemblies, and the second driving gear is in driving connection with the second driving racks corresponding to the second driving racks.

Further, a second intermediate gear is coaxially fixed on the second driving gear, a second driven gear is meshed with the second intermediate gear, and the second driven gear is meshed with a second transmission rack on the side where the second driven gear is located.

Further, the outer covers of the range-increasing gear sets are respectively provided with a gear housing.

The beneficial effects of the utility model are as follows: according to the double-telescopic full-stroke chuck, the clamping jaw is slidably arranged on the sliding seat, and then the sliding seat is slidably arranged on the disk seat along the sliding direction of the clamping jaw, so that the radial space on the disk seat can be repeatedly utilized, and the sliding seat can also provide sliding power for the clamping jaw through the range-increasing gear set during sliding, so that the clamping jaw can move along with the sliding seat and can also independently move relative to the sliding seat, namely, the clamping jaw and the sliding seat can both generate telescopic movement, the radial movement of the clamping jaw with a larger stroke is realized in a smaller radial space, the compactness of the structure is improved, and the miniature and exquisite design of the chuck is realized.

Other features of the present utility model and its advantages are described in detail below in the detailed description of the exemplary embodiments.

Drawings

The utility model will be further described with reference to the drawings and examples.

FIG. 1 is a three-dimensional schematic view of a dual telescopic full stroke chuck;

FIG. 2 is a schematic front view of a dual telescopic full stroke chuck;

FIG. 3 is a three-dimensional schematic view of the power unit and jaw assembly of the dual telescopic full stroke chuck;

FIG. 4 is a three-dimensional schematic view of a dual telescopic full stroke chuck after the disc seat, first cylinder and second cylinder are hidden;

fig. 5 is a three-dimensional schematic view of a jaw assembly equipped with a gear housing and a gear box.

In the figure: 1. a disc seat 11 and a central hole;

2. The clamping jaw assembly, 21, clamping jaws, 22, a sliding seat, 23, a range-extending gear set, 231, cheng Chilun, 232, a movable rack, 233 and a fixed rack; 2a, a first jaw assembly, 2b, a second jaw assembly;

3. The first power assembly, 31, a first linkage ring, 311, a first arc-shaped rack, 32, a first cylinder, 33, a first driving gear, 34, a first intermediate gear, 35, a first driven gear, 36 and a first transmission rack;

4. The second power assembly, 41, a second linkage ring, 411, a second arc-shaped rack, 42, a second cylinder, 43, a second driving gear, 44, a second intermediate gear, 45, a second driven gear, 46 and a second transmission rack;

5. a gear housing;

6. And a gear box.

Detailed Description

The utility model will now be described in further detail with reference to the accompanying drawings. The drawings are simplified schematic representations which merely illustrate the basic structure of the utility model and therefore show only those features which are relevant to the utility model, and orientation and reference (e.g., up, down, left, right, etc.) may be used solely to aid in the description of the features in the drawings. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the claimed subject matter is defined only by the appended claims and equivalents thereof.

As shown in fig. 1-5, a double telescopic full stroke chuck comprises a chuck base 1, a claw assembly 2 and a power unit;

The tray 1 may be penetrated with a central hole 11 for the workpiece to pass through, and the cross section of the central hole 11 may be, but is not limited to, square, circular, etc.;

The plurality of the jaw assemblies 2 are arranged around the center of the chuck, for example, the plurality of jaw assemblies 2 can be uniformly distributed around the axis of the center hole 11, the jaw assemblies 2 comprise jaws 21, a sliding seat 22 and a range-extending gear set 23, the jaw assemblies 2 can be positioned outside the disc seat 1, a roller is rotatably arranged on one side of the jaws 21, which faces the center of the chuck, of the jaws 21, the jaws 21 are slidably arranged on the sliding seat 22, the jaws 21 can be specifically arranged on the sliding seat 22 through linear guide rails, and the sliding seat 22 is slidably arranged on the disc seat 1 along the sliding direction between the jaws 21 and the sliding seat 22, namely, the sliding direction between the jaws 21 and the sliding seat 22 is consistent with the sliding direction between the sliding seat 22 and the disc seat 1; the slide seat 22 can be specifically mounted on the tray seat 1 through a linear guide rail, the range-extending gear set 23 comprises an extension Cheng Chilun 231, and a movable rack 232 and a fixed rack 233 which are respectively meshed with two sides of the extension Cheng Chilun, the extension Cheng Chilun 231 is rotatably mounted on the slide seat 22, the movable rack 232 is fixed on the claw 21, for example, the movable rack 232 is fixed on the claw 21 through a screw, the movable rack 232 can also be integrally formed with the claw 21, and it is noted that when the movable rack 232 and the claw 21 are integrally formed, a tooth socket structure is formed on the claw 21 to form the movable rack 232, the fixed rack 233 is fixed on the tray seat 1, for example, the fixed rack 233 can also be fixed on the tray seat 1 through a screw, the length direction of the fixed rack 233 is parallel or approximately parallel to the length of the movable rack 232, and the length direction of the movable rack 232 is consistent with the sliding direction of the movable rack 232 on the slide seat 22;

the power unit is used for driving the sliding seat 22 on the disc seat 1 to slide;

When the power unit drives the slide seat 22 to extend, the slide seat 22 slides towards the center of the chuck (corresponding to the center of the center hole 11), when the slide seat 22 moves towards the center of the chuck along with the slide seat 22, the increment Cheng Chilun 231 on the slide seat 22 has a meshing relationship with the fixed rack 233, so that the increment Cheng Chilun 231 rotates, the movable rack 232 is driven by self-rotation in the sliding displacement process of the increment Cheng Chilun, and the movable rack 232 and the clamping jaw 21 on the movable rack 232 slide towards the center of the chuck relative to the slide seat 22, so that when the slide seat 22 extends towards the center of the chuck, the clamping jaw 21 can also extend towards the center of the chuck relative to the slide seat 22;

When the power unit drives the slide seat 22 to retract, the slide seat 22 slides along the direction away from the center of the chuck, when the increment Cheng Chilun 231 on the slide seat 22 moves along the direction away from the center of the chuck along with the slide seat 22, the increment Cheng Chilun has a meshing relationship with the fixed rack 233, so that the increment Cheng Chilun 231 can generate autorotation, and the movable rack 232 is driven by autorotation in the sliding displacement process of the increment Cheng Chilun, so that the movable rack 232 and the clamping jaw 21 on the movable rack 232 move along the direction away from the center of the chuck, and the clamping jaw 21 can retract relative to the slide seat 22 when the slide seat 22 is retracted; thereby realizing double telescopic movement of the claw 21 and the slide 22.

The double-telescopic full-stroke chuck utilizes the fact that the clamping jaw 21 is slidably mounted on the sliding seat 22, and then the sliding seat 22 is slidably mounted on the tray seat 1 along the sliding direction of the clamping jaw 21, so that the radial space on the tray seat 1 can be recycled, and the sliding seat 22 can also provide sliding power for the clamping jaw 21 during sliding through the range-increasing gear set 23, so that the clamping jaw 21 can move along with the sliding seat 22 and can also independently move relative to the sliding seat 22, namely, the clamping jaw 21 and the sliding seat 22 can both generate telescopic movement, radial movement of a larger stroke of the clamping jaw 21 can be realized in a smaller radial space, the compactness of the structure is improved, and further, the miniature and exquisite design of the chuck is realized.

Further, two jaw assemblies 2 in all the jaw assemblies 2 are first jaw assemblies 2a, the jaws 21 of the two first jaw assemblies 2a are oppositely arranged in a first direction, and a sliding seat 22 in the first jaw assemblies 2a is slidably arranged on the tray seat 1 in the first direction;

The two claw assemblies 2 are second claw assemblies 2b, claws 21 of the two second claw assemblies 2b are oppositely arranged in the second direction, and a sliding seat 22 in the second claw assemblies 2b is slidably arranged on the tray seat 1 in the second direction;

the first direction and the second direction intersect each other, in particular, the first direction is perpendicular to the second direction;

By arranging the four jaw assemblies 2, the workpiece is clamped in two directions, and the workpiece is easy to clamp.

In some examples, the power unit includes a first power assembly 3 and a second power assembly 4;

The first power assembly 3 is used for simultaneously driving the sliding seat 22 of the two first claw assemblies 2a to slide along the first direction;

The second power assembly 4 is used for simultaneously driving the sliding seat 22 of the two second claw assemblies 2b to slide along the second direction.

Through the design that first jack catch assembly 2a and second jack catch assembly 2b can independently stretch out and draw back, realize that two clamping jaws of first jack catch assembly 2a can independently grasp the work piece in first direction, two clamping jaws 21 of second jack catch assembly 2b can independently grasp the work piece in the second direction to adaptable different shaped work piece, the commonality is good.

In some examples, the first power assembly 3 may be, but is not limited to, a cylinder or an electric push rod, and taking the cylinder as an example of the first power assembly 3, a piston rod of the cylinder as the first power assembly 3 may be directly and fixedly connected with the slide seat 22 of the first power assembly 3, so that the cylinder directly drives the slide seat 22 of the first jaw assembly 2a to move, but the cylinder directly drives the slide seat 22 to move, which may cause a larger radial space occupied by a part where the cylinder is located;

In this regard, the first power assembly 3 may further include a first linkage ring 31 and a first cylinder 32, where the first linkage ring 31 is rotatably installed on the tray seat 1, and one end of the first cylinder 32 is hinged to the tray seat 1, and the other end is hinged to the first linkage ring 31;

The first linkage ring 31 is provided with two first arc racks 311, the first arc racks 311 can be integrally formed with the first linkage ring 31, and the first arc racks 311 can be coaxially arranged with the first linkage ring 31; or the first linkage ring 31 may be a gear ring, and the two first arc racks 311 are part of the gear ring; the two first arc racks 311 are respectively meshed with a first driving gear 33 which is rotationally connected with the tray seat 1, the sliding seat 22 of the first jaw assembly 2a is fixedly provided with a first transmission rack 36, the two first driving gears 33 are in one-to-one correspondence with the first transmission racks 36 of the two first jaw assemblies 2a, and the first driving gears 33 are in transmission connection with the corresponding first transmission racks 36;

The first linkage ring 31 can be driven to rotate through the telescopic movement of the first air cylinder 32, the first arc-shaped rack 311 on the first linkage ring 31 rotates along with the first linkage ring, the first arc-shaped rack 311 drives the first driving gear 33 to rotate, and the first driving gear 33 drives the first transmission rack 36 to move, so that the telescopic movement of the sliding seat 22 is powered, the first air cylinder 32 can be arranged approximately along the circumferential direction of the chuck, the space on the circumferential direction of the chuck is fully utilized, and the compactness of the structure is improved.

In some examples, a first intermediate gear 34 is coaxially fixed on the first driving gear 33, the first intermediate gear 34 is meshed with a first driven gear 35, the first driven gear 35 is rotatably mounted on the tray 1, and the first driven gear 35 is meshed with a first transmission rack 36 on the side of the first driven gear 35;

The first linkage ring 31 can be driven to rotate through the telescopic movement of the first air cylinder 32, the first arc-shaped rack 311 on the first linkage ring 31 rotates along with the first linkage ring, the first arc-shaped rack 311 drives the first driving gear 33 to rotate, the first driving gear 33 drives the first intermediate gear 34 to rotate, the first intermediate gear 34 drives the first driven gear 35 to rotate, and the first driven gear 35 drives the first transmission rack 36 to move along the sliding direction of the sliding seat 22;

The first intermediate gear 34, the first driven gear 35 and the first driving rack 36 are all disposed outside the tray 1, and the first cylinder 32, the first coupling ring 31, the first arc-shaped rack 311 and the first driving gear 33 are all disposed inside the tray 1, so that the compactness of the structure can be improved, and the gear box 6 can be fixed outside the tray 1 to cover the first intermediate gear 34, the first driven gear 35 and the first driving rack 36.

In some examples, the second power assembly 4 may be, but is not limited to, an air cylinder or an electric push rod, and taking the air cylinder as the second power assembly 4 as an example, a piston rod of the air cylinder of the second power assembly 4 may be directly and fixedly connected with the slide seat 22 of the second power assembly 4, so that the air cylinder directly drives the slide seat 22 of the second jaw assembly 2b to move, but the air cylinder directly drives the slide seat 22 to move, which may result in a larger radial space occupied by the location of the air cylinder;

In this regard, the second power assembly 4 may further include a second coupling ring 41 and a second air cylinder 42, where the second coupling ring 41 is rotatably installed on the disc seat 1, and one end of the second air cylinder 42 is hinged to the disc seat 1, and the other end is hinged to the second coupling ring 41;

The second linkage ring 41 is provided with two second arc racks 411, the second arc racks 411 can be integrally formed with the second linkage ring 41, and the second arc racks 411 can be coaxially arranged with the second linkage ring 41; or the second coupling ring 41 may be a gear ring, the two second arc racks 411 are part of the gear ring, the two second arc racks 411 are respectively meshed with a second driving gear 43 rotationally connected with the disc seat 1, the sliding seat 22 of the second jaw assembly 2b is fixed with a second driven rack 32, the two second driving gears 43 are in one-to-one correspondence with the second transmission racks 46 of the two second jaw assemblies 2b, and the second driving gears 43 are in transmission connection with the corresponding second transmission racks 46;

The second air cylinder 42 can drive the second linkage coil 41 to rotate through the telescopic movement of the second air cylinder 42, the second arc-shaped rack 411 on the second linkage coil 41 rotates along with the second linkage coil, the second arc-shaped rack 411 drives the second driving gear 43 to rotate, the second driving gear 43 drives the second transmission rack 46 to move, so as to realize the power supply for the telescopic movement of the sliding seat 22 of the second power assembly 4, the second air cylinder 42 can be arranged along the circumferential direction of the chuck, the space in the circumferential direction is fully utilized, the compactness of the structure is improved,

In some examples, a second intermediate gear 44 is coaxially fixed on the second driving gear 43, the second intermediate gear 44 is meshed with a second driven gear 45, the second driven gear 45 is rotatably mounted on the tray 1, and the second driven gear 45 is meshed with a second transmission rack 46 on the side of the second driven gear 45;

The second linkage ring 41 can be driven to rotate through the telescopic movement of the second air cylinder 42, the first arc-shaped rack 311 on the second linkage ring 41 rotates along with the second linkage ring, the second arc-shaped rack 411 drives the first driving gear 33 to rotate, the second driving gear 43 drives the second intermediate gear 44 to rotate, the second intermediate gear 44 drives the second driven gear 45 to rotate, and the second driven gear 45 drives the second transmission rack 46 to move along the sliding direction of the sliding seat 22;

the second intermediate gear 44, the second driven gear 45 and the second driving rack 46 are all disposed outside the disc seat 1, and the second cylinder 42, the second coupling ring 41, the second arc-shaped rack 411 and the second driving gear 43 are all disposed inside the disc seat 1, so that the compactness of the structure can be improved, and the gear box 6 can be fixed outside the disc seat 1 to cover the second intermediate gear 44, the second driven gear 45 and the second driving rack 46.

In some examples, the range-extending gear sets 23 are each covered with a gear housing 5 to protect the range-extending gear sets 23;

The working principle of the double telescopic full-stroke chuck is as follows:

When the first power assembly 3 drives the sliding seat 22 of the two first jaw assemblies 2a to extend or retract, the range-extending gear set 23 of the first jaw assemblies 2a correspondingly drives the jaws 21 of the first jaw assemblies 2a to extend or retract, so that the jaws 21 and the sliding seat 22 of the first jaw assemblies 2a extend or retract simultaneously;

When the second power assembly 4 drives the sliding seat 22 of the two second jaw assemblies 2b to extend or retract, the range-extending gear set 23 of the second jaw assemblies 2b correspondingly drives the jaws 21 of the second jaw assemblies 2b to extend or retract, so that the jaws 21 and the sliding seat 22 of the second jaw assemblies 2b extend or retract simultaneously.

The above-described preferred embodiments according to the present utility model are intended to suggest that, from the above description, various changes and modifications can be made by the worker in question without departing from the technical spirit of the present utility model. The technical scope of the present utility model is not limited to the description, but must be determined according to the scope of claims.

Claims (8)

1. A dual telescopic full stroke chuck, characterized by: comprising the following steps:

A tray seat (1);

The clamping jaw assembly (2) is provided with a plurality of clamping jaw assemblies (2) which are arranged around the center of the chuck, the clamping jaw assemblies (2) comprise clamping jaws (21), sliding seats (22) and a range-extending gear set (23), the clamping jaws (21) are slidably arranged on the sliding seats (22), the sliding seats (22) are slidably arranged on the tray seat (1) along the sliding direction between the clamping jaws (21) and the sliding seats (22), the range-extending gear set (23) comprises a range-extending Cheng Chilun (231) and a movable rack (232) and a fixed rack (233) which are respectively meshed with two sides of the range-extending Cheng Chilun (231), the range-extending Cheng Chilun (231) is rotatably arranged on the sliding seats (22), the movable rack (232) is fixed on the clamping jaws (21), and the fixed rack (233) is fixed on the tray seat (1);

And the power unit is used for driving the sliding seat (22) on the disc seat (1) to slide.

2. The dual telescopic full stroke chuck of claim 1, wherein: the two jaw assemblies (2) are first jaw assemblies (2 a), the jaws (21) of the two first jaw assemblies (2 a) are oppositely arranged in a first direction, and a sliding seat (22) in the first jaw assemblies (2 a) is slidably arranged on the tray seat (1) along the first direction;

The two jaw assemblies (2) are second jaw assemblies (2 b), the jaws (21) of the two second jaw assemblies (2 b) are oppositely arranged in the second direction, and the sliding seat (22) in the second jaw assemblies (2 b) is slidably arranged on the tray seat (1) along the second direction;

The first direction and the second direction are intersected with each other.

3. The dual telescopic full stroke chuck of claim 2, wherein: the power unit comprises a first power assembly (3) and a second power assembly (4);

The first power assembly (3) is used for simultaneously driving the sliding seat (22) of the two first claw assemblies (2 a) to slide along a first direction;

The second power assembly (4) is used for simultaneously driving the sliding seat (22) of the two second claw assemblies (2 b) to slide along the second direction.

4. A dual telescopic full stroke chuck according to claim 3, wherein: the first power assembly (3) comprises a first linkage ring (31) and a first air cylinder (32), wherein the first linkage ring (31) is rotatably arranged on the tray seat (1), one end of the first air cylinder (32) is hinged with the tray seat (1), and the other end of the first air cylinder is hinged with the first linkage ring (31);

The novel movable clamping device is characterized in that the first linkage ring (31) is provided with two first arc racks (311), the two first arc racks (311) are respectively meshed with a first driving gear (33) which is rotationally connected with the disc seat (1), a first transmission rack (36) is fixed on the sliding seat (22) of the first clamping jaw assembly (2 a), the two first driving gears (33) are in one-to-one correspondence with the first transmission racks (36) of the two first clamping jaw assemblies (2 a), and the first driving gears (33) are in transmission connection with the corresponding first transmission racks (36).

5. The dual telescopic full stroke chuck according to claim 4, wherein: a first intermediate gear (34) is coaxially fixed on the first driving gear (33), a first driven gear (35) is meshed with the first intermediate gear (34), and the first driven gear (35) is meshed with a first transmission rack (36) on the side where the first driven gear is located.

6. A dual telescopic full stroke chuck according to claim 3, wherein: the second power assembly (4) comprises a second linkage ring (41) and a second air cylinder (42), the second linkage ring (41) is rotatably arranged on the tray seat (1), one end of the second air cylinder (42) is hinged with the tray seat (1), and the other end of the second air cylinder is hinged with the second linkage ring (41);

The second linkage ring (41) is provided with two second arc racks (411), the two second arc racks (411) are respectively meshed with a second driving gear (43) which is rotationally connected with the disc seat (1), a second transmission rack (46) is fixed on the sliding seat (22) of the second jaw assembly (2 b), the two second driving gears (43) are in one-to-one correspondence with the second transmission racks (46) of the two second jaw assemblies (2 b), and the second driving gears (43) are in transmission connection with the second transmission racks (46) corresponding to the second driving gears.

7. The dual telescopic full stroke chuck of claim 6, wherein: a second intermediate gear (44) is coaxially fixed on the second driving gear (43), a second driven gear (45) is meshed with the second intermediate gear (44), and the second driven gear (45) is meshed with a second transmission rack (46) on the side where the second driven gear (45) is located.

8. The dual telescopic full stroke chuck of claim 6, wherein: the outer of the range-increasing gear sets (23) is covered with a gear housing (5).