CN114824977A

CN114824977A - Three-terminal applicable device

Info

Publication number: CN114824977A
Application number: CN202210321885.XA
Authority: CN
Inventors: 张华羽; 王亮; 李辉权; 杨梓聪
Original assignee: Shenzhen Power Supply Bureau Co Ltd
Current assignee: Shenzhen Power Supply Bureau Co Ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-07-29
Anticipated expiration: 2042-03-30
Also published as: CN114824977B

Abstract

The invention relates to a three-end applicable device which comprises a shell, two connecting pieces and an adjusting assembly, wherein the shell is provided with two through holes in opposite positions, the adjusting assembly is arranged in the shell, the length directions of the two connecting pieces are along a first direction and are respectively arranged at two ends of the adjusting assembly along the first direction, and the adjusting assembly has a first state and a second state. When specifically using, directly place three terminal suitable type device in electronic equipment to make two through-holes on the casing of three terminal suitable type device correspond with the mounting hole position on the electronic equipment respectively, then adjust adjusting part to first state, two connecting pieces move to one side of keeping away from each other promptly, pass the through-hole respectively until the tip of two connecting pieces, insert in the mounting hole of electronic equipment, accomplish three terminal suitable type device promptly and electronic equipment's fixed. When the device is installed, the three-end applicable device can be installed without the help of external installation equipment, and the installation process is simple and quick.

Description

Three-terminal applicable device

Technical Field

The invention relates to the technical field of electronic equipment, in particular to a three-terminal applicable device.

Background

The three-terminal adaptive device is used for synchronizing data of the mobile phone terminal, the computer terminal and the VR terminal, and can be installed in any one of a computer host, a mobile phone or a VR electronic device. When the data of the three terminals are required to be synchronized, the mobile phone, the computer and the VR equipment are connected simultaneously in a wireless or wired mode, and the data synchronization between the two or all electronic equipment can be realized through a three-terminal adaptive device arranged in a computer host, the mobile phone or the VR electronic equipment.

However, in the prior art, when the three-terminal adaptive device is installed, external parts are required to be matched with external installation equipment to install the device into a computer host, a mobile phone or a VR electronic device, and the operation is complex.

Disclosure of Invention

In view of this, it is necessary to provide a three-terminal-compatible device in order to solve the problem that the three-terminal-compatible device is complicated to install.

A three-terminal adaptive device comprising:

the shell is provided with two through holes opposite in position;

the mounting mechanism is arranged in the shell and comprises two connecting pieces and an adjusting component, the length direction of the connecting pieces is along a first direction, the two connecting pieces are respectively arranged at two ends of the adjusting component along the first direction, and the adjusting component has a first state and a second state;

when the adjusting assembly is in a first state, the two connecting pieces are far away from each other, and the end parts, far away from each other, of the two connecting pieces respectively penetrate through the through holes so as to be inserted into the mounting holes of the electronic equipment;

when the adjusting assembly is in the second state, the two connecting pieces are close to each other, and the end parts, far away from each other, of the two connecting pieces are used for being separated from the mounting hole of the electronic equipment.

In one embodiment, the connecting member is a screw rod, the adjusting assembly includes a sleeve and a limiting member, the sleeve is rotatably connected to the housing, one end of the screw rod is inserted into the sleeve and is in threaded engagement with the sleeve, and the limiting member is connected to the screw rod for limiting the rotation of the screw rod.

In one embodiment, the screw rod is provided with a sliding groove along a first direction, one end of the limiting member is fixedly connected with the housing, and the other end of the limiting member is in sliding fit with the sliding groove.

In one embodiment, the outer wall of the sleeve is provided with an external thread, the mounting mechanism further comprises a worm, the length direction of the worm is along a second direction, the worm is matched with the external thread of the sleeve, one end of the worm extends out of the shell, and the first direction is perpendicular to the second direction.

In one of them embodiment, the three-terminal suitable type device still includes heat dissipation mechanism, heat dissipation mechanism includes power component, lead screw, coupling assembling and fan assembly, power component is used for driving the lead screw rotates, the coupling assembling cover is established on the lead screw, coupling assembling with fan assembly connects, is used for driving simultaneously fan assembly centers on the lead screw rotates and follows the length direction of lead screw removes.

In one embodiment, the connection assembly includes:

the reciprocating sleeve is sleeved on the screw rod and is in threaded fit with the screw rod, an annular groove is further formed in the reciprocating sleeve, and the axis of the annular groove is overlapped with the axis of the screw rod;

the rotating sleeve comprises a first rotating sleeve and a second rotating sleeve which are sequentially connected, the inner diameter of the first rotating sleeve is larger than that of the second rotating sleeve, so that the first rotating sleeve is rotatably connected with the annular groove, and the second rotating sleeve is in threaded fit with the screw rod; and

and the rotation limiting piece is connected with the reciprocating moving sleeve and used for limiting the reciprocating moving sleeve to rotate.

In one embodiment, the power assembly comprises:

a motor;

the output shaft of the motor is connected with the driving bevel gear;

and the driven bevel gear is meshed with the driving bevel gear and is connected with the screw rod and used for driving the screw rod to rotate.

In one embodiment, a heat dissipation port is formed in the shell, a dust screen is arranged in the heat dissipation port, the power assembly is arranged at the first end of the screw rod, the second end of the screw rod is rotatably connected with the shell, a dust removing fan is arranged at the second end of the screw rod, and the dust removing fan is located on the inner side of the dust screen.

In one embodiment, the three-terminal-adapted device further comprises a dust removal mechanism, the dust removal mechanism comprising:

the mounting shaft is arranged on the connecting assembly, and the length direction of the mounting shaft is perpendicular to the axial direction of the screw rod;

and the ash removing roller is sleeved at least one end of the mounting shaft.

In one embodiment, the dust removing mechanism further comprises a rack, two ends of the rack are respectively fixed with the shell, the rack is located on at least one side of the screw rod, and the length direction of the rack is parallel to the length direction of the screw rod;

the installation epaxial rotation of epaxial gear that is connected with, the gear with rack drive cooperation, just the gear with the deashing roller is connected, and when coupling assembling drove the installation axle is followed when the lead screw length direction removes, the gear drives the deashing roller rotates.

The three-end adaptive device is provided with the adjusting assembly and the connecting pieces, the connecting pieces are arranged at the two end parts of the adjusting assembly, and when the adjusting assembly is switched between the first state and the second state, the two connecting pieces can stretch in the first direction. When specifically using, directly place three terminal suitable type device in electronic equipment to make two through-holes on the casing of three terminal suitable type device correspond with the mounting hole position on the electronic equipment respectively, then adjust adjusting part to first state, two connecting pieces move to one side of keeping away from each other promptly, pass the through-hole respectively until the tip of two connecting pieces, insert in the mounting hole of electronic equipment, accomplish three terminal suitable type device promptly and electronic equipment's fixed. When the device is installed, the three-end applicable device can be installed without the help of external installation equipment, and the installation process is simple and quick. When the three-terminal adaptive device needs to be detached, the adjusting assembly is adjusted to be in a second state, namely the two connecting pieces are close to each other, and the two connecting pieces are separated from the mounting hole of the electronic equipment. The disassembly process also needs any tool, and the disassembly is convenient and quick.

Drawings

FIG. 1 is a schematic diagram of an external structure of a three-terminal adaptive device according to an embodiment;

FIG. 2 is a schematic structural view of the mounting mechanism;

FIG. 3 is a schematic structural diagram of a heat dissipation mechanism and a dust removal mechanism;

FIG. 4 is a schematic structural view of the connecting assembly;

FIG. 5 is an enlarged schematic view of the structure at A in FIG. 3;

fig. 6 is a schematic structural view of the dust removing fan.

Reference numerals: 100-a housing; 110-a heat sink; 140-a through hole;

200-an installation mechanism; 210-a connector; 220-an adjustment assembly; 221-a sleeve; 222-a stop; 230-a worm;

310-a power assembly; 311, a motor; 312-drive bevel gear; 313-driven bevel gear; 320-a screw rod; 330-a connecting component; 331-reciprocating sleeve; 3311-annular groove; 332-rotating sleeve; 3321-first rotating sleeve; 3322-a second rotating sleeve; 340-a fan assembly;

410-mounting the shaft; 420-a deashing roller; 430-gear; 440-a dust removal fan; 441-end piece; 442-fan blades; 443-dust removing mat; 450-rack.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to FIGS. 1 and 2, one embodiment of the present invention provides a three-terminal device comprising a housing 100 and a mounting mechanism 200. The housing 100 is provided with two through holes 140 at opposite positions. The mounting mechanism 200 is disposed within the housing 100. The mounting mechanism 200 includes two connectors 210 and an adjustment assembly 220. The length direction of the connecting member 210 is along the first direction, and the connecting member is respectively disposed at two ends of the adjusting assembly 220 along the first direction. The adjustment assembly 220 has a first state and a second state. When the adjusting assembly 220 is in the first state, the two connectors 210 are away from each other, and the ends of the two connectors 210 away from each other respectively pass through the through holes 140 for inserting into the mounting holes of the electronic device. When the adjusting assembly 220 is in the second state, the two connectors 210 are close to each other, and the end portions of the two connectors 210 far away from each other are used for being disengaged from the mounting holes of the electronic device.

In the present embodiment, by providing the adjustment assembly 220 and the connecting members 210, the connecting members 210 are provided at both ends of the adjustment assembly 220, and when the adjustment assembly 220 is switched between the first state and the second state, the two connecting members 210 can be made to extend and contract in the first direction. When the three-terminal-suitable device is used specifically, the three-terminal-suitable device is directly placed in the electronic device, the two through holes 140 in the shell 100 of the three-terminal-suitable device are respectively aligned with the mounting holes in the electronic device, and then the adjusting assembly 220 is adjusted to the first state, that is, the two connecting pieces 210 move to the sides away from each other until the ends of the two connecting pieces 210 respectively penetrate through the through holes 140 and are inserted into the mounting holes in the electronic device, so that the three-terminal-suitable device and the electronic device are fixed. When the device is installed, the three-end applicable device can be installed without the help of external installation equipment, and the installation process is simple and quick. When the three-terminal compatible device needs to be removed, the adjusting assembly 220 is adjusted to the second state, that is, the two connectors are close to each other, and the two connectors 210 are separated from the mounting holes of the electronic device. The disassembly process also needs any tool, and the disassembly is convenient and quick.

In some embodiments, referring to fig. 2, the connecting member 210 is a screw, the adjusting assembly 220 includes a sleeve 221 and a limiting member 222, the sleeve 221 is rotatably connected to the casing 100, one end of the screw is inserted into the sleeve 221 and is in threaded engagement with the sleeve 221, and the limiting member 222 is connected to the screw for limiting the rotation of the screw. When the adjusting assembly 220 is in the first state, the sleeve 221 rotates forward, and the two screws respectively extend out of the sleeve 221. When the adjustment unit 220 is in the second state, the sleeve 221 is reversely rotated, and the two screws are retracted into the sleeve 221.

In the present embodiment, the sleeve 221 rotates in the forward direction along the axial direction, and the forward direction may be in the counterclockwise direction or the clockwise direction, and the rotation direction of the sleeve 221 is not limited herein. As long as the adjustment assembly 220 is in the first state and the second state, the rotation direction of the sleeve 221 is opposite. The stopper 222 restricts rotation of the screws, that is, the screws cannot rotate, and when the sleeve 221 rotates, the two screws respectively retract into the sleeve 221 or extend out of the sleeve 221, thereby enabling mounting and dismounting of the three-terminal-suitable device and the electronic apparatus.

In one embodiment, the screw has a sliding slot along the first direction, and one end of the limiting member 222 is fixedly connected to the casing 100, and the other end thereof is slidably engaged with the sliding slot. When the sleeve 221 rotates, one end of the limiting member 222 is fixed to the housing 100, and the other end of the limiting member 222 is engaged with the sliding slot formed in the screw rod along the first direction, so that the other end of the limiting member 222 is used for preventing the screw rod from rotating, and the rotating motion of the sleeve 221 is converted into the linear motion of the screw rod. When the screw rod moves in the first direction, the limiting member 222 slides in the sliding groove.

In another embodiment, the housing may further include a sliding groove formed along the upper edge thereof in the first direction, one end of the limiting member is fixedly connected to the screw rod, and the other end thereof is in sliding fit with the sliding groove.

In some embodiments, the sleeve 221 is provided with an external thread on an outer wall thereof, the three-terminal-adapted device further includes a worm 230, a length direction of the worm 230 is along the second direction, the worm 230 is engaged with the external thread of the sleeve 221, and one end of the worm 230 protrudes out of the housing 100, the first direction is perpendicular to the second direction.

In this embodiment, one end of the worm 230 extends out of the casing 100, that is, during installation, the worm 230 only needs to be rotated outside the casing 100, so that the worm 230 drives the sleeve 221 to rotate, and the sleeve 221 rotates to extend and retract the screw rod, so that the installation is convenient and fast.

In other embodiments, the adjusting assembly may also be an air cylinder, and the connecting member is an expansion link connected to the air cylinder, that is, the expansion or retraction of the connecting member may also be achieved by the air cylinder.

In some embodiments, referring to fig. 3, the three-terminal adaptive device further includes a heat dissipation mechanism, the heat dissipation mechanism includes a power assembly 310, a screw 320, a connection assembly 330 and a fan assembly 340, the power assembly 310 is configured to drive the screw 320 to rotate, the connection assembly 330 is sleeved on the screw 320, and the connection assembly 330 is connected to the fan assembly 340 and configured to drive the fan assembly 340 to rotate around the screw 320 and move along the length direction of the screw 320.

In this embodiment, the fan assembly 340 is disposed on the screw rod 320 through the connecting assembly 330, and when the screw rod 320 rotates, the connecting assembly 330 is used to drive the fan assembly 340 to move, and compared with a mode in which a fan in the prior art can only rotate in situ, the position of the fan assembly 340 in this embodiment can move, which is beneficial to accelerating air circulation, thereby achieving a better heat dissipation effect. Secondly, in this embodiment, only the screw 320 needs to rotate, and the fan assembly 340 can be driven to move and rotate at the same time, that is, the fan assembly 340 does not need to be provided with the separate power assembly 310, and the rotation of the fan can be realized, so that the energy-saving effect is good.

Further, in conjunction with fig. 4, the connecting assembly 330 includes a reciprocating sleeve 331, a rotating sleeve 332, and a rotation limiting member. The reciprocating sleeve 331 is sleeved on the screw rod 320 and is in threaded fit with the screw rod 320, an annular groove 3311 is further formed in the reciprocating sleeve 331, and the axis of the annular groove 3311 coincides with the axis of the screw rod 320. The rotary sleeve 332 includes a first rotary sleeve 3321 and a second rotary sleeve 3322 which are sequentially connected, and the first rotary sleeve 3321 has an inner diameter greater than that of the second rotary sleeve 3322 so that the first rotary sleeve 3321 is rotatably connected to the annular groove 3311 and the second rotary sleeve 3322 is screw-coupled to the screw 320. The rotation limiting member is connected to the reciprocating sleeve 331 for limiting the rotation of the reciprocating sleeve 331 around the screw 320.

In the present embodiment, the rotating sleeve 332 is in threaded fit with the lead screw 320, that is, when the lead screw 320 rotates, the rotating sleeve 332 can be driven by the lead screw 320 to rotate, that is, the rotating sleeve 332 can enable the fan assembly 340 to rotate around the lead screw 320. The reciprocating sleeve 331 is screw-engaged with the screw 320, and the rotation restricting member makes the reciprocating sleeve 331 not to rotate, i.e., the reciprocating sleeve 331 can move along the screw 320 when the screw 320 rotates. And because the first rotary sleeve 3321 with the larger inner diameter of the rotary sleeve 332 is arranged in the annular groove 3311 of the reciprocating sleeve 331 in a penetrating manner and is rotationally connected with the annular groove 3311, the reciprocating sleeve 331 can drive the rotary sleeve 332 to move along the screw rod 320 while moving along the screw rod 320, so that the rotary sleeve 332 can rotate and move, namely, the fan assembly 340 can be moved and rotated simultaneously only under the condition that the screw rod 320 rotates.

Specifically, referring to fig. 3, the power assembly 310 includes a motor 311, a drive bevel gear 312, and a driven bevel gear 313. An output shaft of the motor 311 is connected to the drive bevel gear 312. The driven bevel gear 313 is engaged with the drive bevel gear 312, and the driven bevel gear 313 is connected with the screw 320 and is used for driving the screw 320 to rotate. The direction of the output shaft of the motor 311 can be changed by the arrangement of the driving bevel gear 312 and the driven bevel gear 313, so that the direction of the output shaft of the motor 311 is different from the length direction of the lead screw 320, and the power assembly 310 and the lead screw 320 can be flexibly arranged in the limited-size shell 100. The structure of the rotation limiting member may be similar to that of the rotation limiting member 222, that is, a sliding slot is disposed on the casing 100, one end of the rotation limiting member 222 is slidably connected to the sliding slot, and the other end is fixed to the reciprocating sleeve 331.

In some embodiments, the casing 100 is provided with a heat dissipating opening 110, a dust screen is disposed in the heat dissipating opening 110, the power assembly 310 is disposed at a first end of the screw 320, a second end of the screw 320 is rotatably connected to the casing 100, and a dust removing fan 440 is disposed at a second end of the screw 320, wherein the dust removing fan 440 is located inside the dust screen. The lead screw 320 can continuously clean the dust screen located at the second end of the lead screw 320 when rotating, so that dust is not easy to stick on the dust screen, and the influence of mesh blockage on the heat dissipation effect is avoided. Specifically, referring to fig. 6, the dust removing fan 440 includes an end plate 441, a fan blade 442 is fixedly mounted outside the end plate 441, and a dust removing pad 443 is disposed on a side wall of the fan blade 442.

In some embodiments, referring to fig. 3 and 5, the three-terminal-adapted device further includes a dust removing mechanism, the dust removing mechanism includes a mounting shaft 410 and a dust removing roller 420, the mounting shaft 410 is disposed on the connection assembly 330, and a length direction of the mounting shaft 410 is perpendicular to a rotation axis of the screw 320. The ash removing roller 420 is sleeved on at least one end of the mounting shaft 410. That is, when coupling assembling 330 is at the in-process that removes, can drive installation axle 410 and also remove along the length direction of lead screw 320, the deashing roller 420 that is located an end of installation axle 410 or two ends can continuously clean the electronic structure chip in the three-terminal suitable type device promptly, plays the deashing effect on the good electronic structure chip, can avoid the dust to pile up on electronic structure, causes the service failure in the device.

Further, the dust removing mechanism further comprises a rack 450, two ends of the rack 450 are respectively fixed with the housing 100, the rack 450 is located on at least one side of the screw 320, and the length direction of the rack 450 is parallel to the length direction of the screw 320. The mounting shaft 410 is rotatably connected with a gear 430, the gear 430 is in transmission fit with a rack 450, and the gear 430 is connected with the ash removal roller 420.

In this embodiment, when the mounting shaft 410 is driven by the connecting assembly 330 to move along the lead screw 320, the gear 430 can be meshed with the rack 450, so as to rotate, i.e. the ash removal roller 420 can be synchronously driven to move and rotate, so that the ash removal roller 420 can better wipe the electronic structure chips in the device.

In addition, since the gear 430 mounted on the mounting shaft 410 is always engaged with the rack 450, the mounting shaft 410 does not rotate following the coupling assembly 330, and the mounting shaft 410 acts on the coupling assembly 330 as a rotation stopper, so that the mounting shaft 410 can be directly used as a rotation stopper.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent should be subject to the appended claims.

Claims

1. A three-terminal adaptive device, comprising:

the shell is provided with two through holes opposite in position;

2. The three-terminal adaptive device according to claim 1, wherein the connecting member is a screw, the adjusting assembly comprises a sleeve and a limiting member, the sleeve is rotatably connected to the housing, one end of the screw is inserted into the sleeve and is in threaded engagement with the sleeve, and the limiting member is connected to the screw for limiting the rotation of the screw.

3. The three-terminal adaptive device according to claim 2, wherein the screw rod is provided with a sliding slot along a first direction, one end of the limiting member is fixedly connected with the housing, and the other end of the limiting member is in sliding fit with the sliding slot.

4. The three-terminal adaptive device according to claim 2, wherein the sleeve has an external thread on an outer wall thereof, the mounting mechanism further comprises a worm having a length along a second direction, the worm is engaged with the external thread of the sleeve, and one end of the worm extends out of the housing, and the first direction is perpendicular to the second direction.

5. The three-terminal adaptive device according to claim 1, further comprising a heat dissipation mechanism, wherein the heat dissipation mechanism comprises a power assembly, a lead screw, a connection assembly and a fan assembly, the power assembly is used for driving the lead screw to rotate, the connection assembly is sleeved on the lead screw, and the connection assembly is connected with the fan assembly and is used for driving the fan assembly to rotate around the lead screw and move along the length direction of the lead screw.

6. The three-terminal-compatible device of claim 5, wherein the connection assembly comprises:

7. The three-terminal-compatible apparatus of claim 5, wherein the power assembly comprises:

a motor;

the output shaft of the motor is connected with the driving bevel gear;

8. The three-terminal adaptive device according to claim 7, wherein the housing is provided with a heat dissipating opening, a dust screen is disposed in the heat dissipating opening, the power assembly is disposed at the first end of the lead screw, the second end of the lead screw is rotatably connected to the housing, and a dust removing fan is disposed at the second end of the lead screw and located inside the dust screen.

9. The three-terminal adaptive device according to any one of claims 5-8, further comprising a dust removing mechanism, the dust removing mechanism comprising:

and the ash removing roller is sleeved at least one end of the mounting shaft.

10. The three-terminal adaptive device according to claim 9, wherein the dust removing mechanism further comprises a rack, two ends of the rack are respectively fixed with the housing, the rack is located on at least one side of the screw rod, and the length direction of the rack is parallel to the length direction of the screw rod;