US20080190333A1

US20080190333A1 - Linear Table Structure

Info

Publication number: US20080190333A1
Application number: US11/672,949
Authority: US
Inventors: Chin-Hsing CHUO; Chi-Pin CHOU
Original assignee: Hiwin Mikrosystem Corp
Current assignee: Hiwin Mikrosystem Corp
Priority date: 2007-02-08
Filing date: 2007-02-08
Publication date: 2008-08-14

Abstract

A linear table structure comprises a groove body, a first screw, a second screw, two sliding seats, and a connecting calibrating assembly. One end of the first screw and that of the second screw are connected and supported by the connecting calibrating assembly, and the positioning portion of the connecting calibrating assembly is used to adjust the pitch error generated on the first and second screws by the sliding seats, thus reducing machining time and cost.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a table structure, and more particularly to a linear table structure.
2. Description of the Prior Art
A conventional double sliding-seat linear table 10 (as shown in FIG. 1) serves as a holding and positioning device and comprises a groove body 11, a screw 12, and two sliding seats 13.
The groove body 11 is defined with a receiving space 111. A first threaded section 121 and a second threaded section 122 are coaxially and symmetrically formed on the outer surface at both ends of the screw 12. Both ends of the screw 12 are pivotally connected to the opposite inner surfaces of the receiving space 111 of the groove body 11. Each of the sliding seats 13 is disposed at its bottom with two nuts 131 through which the sliding seats 13 are fixed to the first and second threaded sections 121 and 122, respectively. The nuts 131 of the sliding seats 13 are meshed with the clockwise thread of the first threaded section 121 and the counterclockwise thread of the second thread section 122, such that when the screw 12 rotates, the nuts 131 will drive the two sliding seats 13 to move relative to each other. However, this conventional linear table has the following disadvantages:
First, the first threaded section 121 and the second threaded section 122 are coaxially and symmetrically formed on the single screw 12 by precision machining, and the precision machining is cost intensive and time consuming.
Second, the positions of the threads machined on the nut 131 of the sliding seats 13 are different, therefore, it is impossible to control the relative position of the two sliding seats 13 accurately. Plus the single-screw machining is unable to provide displacement tolerance for calibrating the sliding seats 13, thus the calibration difficulty is relatively increased, and when doing calibrating operation, it needs an additional adjustment mechanism, thus increasing the cost.
Third, since it is pivotally disposed in the receiving space 111 of the groove body 11, the screw 12 is likely to oscillate during rotation. The length of the screw 12 is determined by the degree of oscillation, and if the screw 12 oscillates too violently, it will severely affect the precision of the displacement of the sliding seats 13.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a linear table structure whose first and second screws are connected by a connecting calibrating assembly, thus reducing cost and time for machining the threads.
To obtain the abovementioned objective, the linear table structure in accordance with the present invention comprises a groove body, a first screw, a second screw, two sliding seats, and a connecting calibrating assembly. The connecting calibrating assembly is formed at either end thereof with a positioning portion, and the first and second screw are positioned and connected by the connecting calibrating assembly. The clockwise thread of the first threaded section of the first screw is located opposite the counterclockwise thread of the second threaded section of the second screw. Thus, by simply exchanging the direction of the thread of the first screw or the second screw, the sliding seats can be adjusted to move relative to each other without processing the threads with precision machining, thus reducing the cost and machining time.
The secondary objective of the present invention is to provide a linear table structure capable of adjusting the pitch error of the sliding seats and ensuring the displacement precision of the sliding seats.
To obtain the abovementioned objective, the linear table structure in accordance with the present invention comprises a groove body, a first screw, a second screw, two sliding seats, and a connecting calibrating assembly. The connecting calibrating assembly is formed at either end thereof with a positioning portion, and the first and second screw utilizes the positioning portion of the connecting calibrating assembly to perform tension adjustment. By such arrangements, when position deviation of the sliding seats occurs, the first and second screws will utilize the positioning portion of the connecting calibrating assembly to perform positioning or adjustment function, thus ensuring the precision displacement of the sliding seat along the first and second screws.
The third objective of the present invention is to provide a linear table structure capable of utilizing an assistant member share the weight of the first and second screws, thus avoiding excessive oscillation and enabling the sliding seats to slide smoothly.
To obtain the abovementioned objective, the linear table structure in accordance with the present invention comprises a groove body, a first screw, a second screw, two sliding seats, a connecting calibrating assembly, and an assistant member. The first and second screw can utilize the assistant member pivotally disposed beside the connecting calibrating assembly to form a single support point or double support points on the groove body. With the connection and support of the connecting calibrating assembly, the first screw or the second screw utilizes the assistant member to disperse the weight supported by the connecting calibrating assembly, thus avoiding excessive oscillation of the first and screw screws, ensuring the displacement stability of the sliding seats, and consequently enabling the sliding seats to slide smoothly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross sectional view of a conventional linear table;

FIG. 2 is a side cross sectional view in accordance with the present invention of showing a linear table structure without assistant member;

FIG. 3 is a side cross sectional view in accordance with the present invention of showing a linear table structure with a single assistant member;

FIG. 4 is a side cross sectional view in accordance with the present invention of showing a linear table structure with two assistant members;

FIG. 5 is an amplified view in accordance with the present invention of showing a part of the linear table structure;

FIG. 6 is another amplified view in accordance with the present invention of showing a part of the linear table structure; and

FIG. 7 is a cross sectional view in accordance with the present invention of showing a connecting calibrating assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be more clear from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention.
Referring to FIGS. 2-7, a linear table structure in accordance with the present invention comprises: a groove body 20, a first screw rod 30, a second screw rod 40, two sliding seats 50, a connecting calibrating assembly 60, and an assistant member 70.
The groove body 20 is interiorly defined with a receiving space 21.
The first screw 30 is formed on its outer surface with a first threaded section 31, at one end of the first threaded section 31 is axially formed a first pivot portion 32, and at the other end of the first threaded section 31 is axially formed a first connecting portion 33.
The second screw 40 is formed on its outer surface with a second threaded section 41 whose pitch is the same as the pitch of the first threaded section 31 of the first screw 30, at one end of the second threaded section 41 is formed a second pivot portion 42, and at the other end of the second threaded section 41 is formed a second connecting portion 43.
Each of the sliding seats 50 includes a base 51 and two nuts 52. The base 51 is a rectangular board, the nuts 52 are radially fixed to the bottom of the base 51, so that the sliding seats 50 are fixed to the first threaded section 31 of the first screw 30 and the second threaded section 41 of the second screw 40, respectively, by the nuts 52.
The connecting calibrating assembly 60 is a cylinder-shaped and includes two positioning portions 61 defined at both ends of the connecting calibrating assembly 60.
Each of the positioning portions 61 includes an inserting groove 62, a positioning hole 63, and a restricting member 64.
The inserting groove 62 is axially defined in the positioning portion 61 for insertion of the first connecting portion 33 of the first screw 30 and the second connecting portion 43 of the second screw 40, respectively. And then the first pivot portion 32 of the first screw 30 and the second pivot portion 42 of the second screw 40 are pivotally disposed on the inner surface of both sides of the groove body 20. The first screw 30 and the second screw 40 are disposed in the receiving space 21 of the groove body 20 in such a manner that the first threaded section 31 of the first screw 30 is located opposite the second threaded section 41 of the second screw 40, so that the sliding seats 50 move relative to each other along with the rotation of the first and second screws 30 and 40.
The positioning hole 63 formed with inner threads is radially defined in the outer surface of the positioning portion 61 and is in communication with the inserting groove 62.
The restricting member 64 formed with outer threads is pressed against the first connecting section 33 of the first screw 30 and the second connecting section 43 of the second screw 40 by screwing through positioning hole 64. When any one of the sliding seats 50 deviates, one of the restricting members 64 of the connecting calibrating assembly 60 can be loosened to adjust the relative position of the first threaded section 31 of the first screw 30 or the second threaded section 41 of the second screw 40. After adjustment, the restricting member 64 can be screwed in the positioning hole 64 against until it is pressed against the first connecting section 33 of the first screw 30 or the second connecting section 43 of the second screw 40. Therefore, it ensures the displacement precision of the sliding seats 50 without worrying that the thread positions of the nuts 52 are different.
The assistant member 70 is a bearing used to relieve the oscillation caused by the rotation of the first screw 30 (as shown in FIGS. 3 and 4) and the second screw 40.
The assistant member 70 is pivotally mounted on the first threaded portion 31 of the screw 30 beside the first pivot connection to form a single support point on the groove body 20.
The assistant member 70 is pivotally mounted on the second threaded portion 41 of the second screw 40 beside the second pivot portion to form another single support point on the groove body 20.
Of course, on each of the first threaded portion 31 of the screw 30 and the second threaded portion 41 of the second screw 40 beside the first and second pivot portions can be disposed an assistant member 70, thus forming two support points on the groove body 20. The assistant member 70 not only reduces the weight supported by the connecting calibrating assembly 60 and improves the stability of rotation, but also prevents the first screw 30 and the second screw 40 from excessive oscillation, and consequently ensuring the precision displacement of the sliding seats 50 along the first and second screws 30 and 40.
The positioning portion 61′ of a connecting calibrating assembly 60′ in accordance with a second embodiment of the present invention is shown in FIG. 7 and includes a C-shaped retainer 62′, a pulling member 63′, a pivot 64′, a screw 65′, and a nut 66′.
The C-shaped retainer 62′ is formed at either end of the connecting calibrating assembly 60′ for insertion of the first and second screws 30 and 40, respectively. One end of the pulling member 63′ is pivotally connected at one end of the screw 65′ by the pivot 64′, the screw 65′ is inserted through both ends of the C-shaped retainer 62′, and the pulling member 63′ is disposed on the C-shaped retainer 62′. Both ends of the C-shaped retainer 62′ are limited by the pulling member 63′ and the nut 66′, the user only needs to pull the pulling member 63′, the screw 65′ will be caused to adjust the tension of the C-shaped retainer 62′, and then the first and second screws 30 and 40 rotate to adjust the displacement error of the sliding seats 50.
The abovementioned linear table structure comprises the sliding seat 50 moveably disposed on the first screw 30 and another sliding seat 50 moveably disposed on the second screw 40, and the two sliding seats 50 move relative to each other. Of course, with the function of connection and calibration of the connecting calibrating assembly 60, the number of the sliding seats and the screws can be adjusted according to need, and the number of the assistant member 70 can be adjusted according to the degree of oscillation of the screws.
For a better understanding of the present invention, its operation and function, reference should be made to FIGS. 2-7 again while reading the following descriptions:
A. The first screw 30 and the second screw 40 are connected through the inserting groove 62 of the connecting calibrating assembly 60, the clockwise thread of the first threaded section 31 of the first screw 30 is located opposite the counterclockwise thread of the second threaded section 41 of the second screw 40.
As mentioned above that the first screw 30 and the second screw 40 are connected by the connecting calibrating assembly 60, by simply exchanging the direction of the thread of the first screw 30 or the second screw 40, the sliding seats 50 can be adjusted to move relative to each other without processing the threads with precision machining, thus reducing the cost and machining time.
B. The first screw 30 and the second screw 40 are connected, positioned and adjusted by the positioning portion 61 of the connecting calibrating assembly 60.
As can be seen from the above description, when position deviation of the sliding seats 50 occurs, the first screw 30 and the second screw 40 will utilize the positioning portion 61 of the connecting calibrating assembly 60 to perform positioning or adjustment function, enabling the user to easily adjust the pitch error caused on the first and second screws 30 and 40 by the sliding seats 50, thus ensuring the precision displacement of the sliding seat 50 along the first and second screws 30 and 40.
C. The first screw 30 or the second screw 40 can be provided with an assistant member 70 beside the connecting calibrating assembly 60 to form a single support point or a double support point on the groove body 20.
With the connection of the connecting calibrating assembly 60, the first screw 30 or the second screw 40 utilizes the assistant member 70 to disperse the weight supported by the connecting calibrating assembly 60, thus avoiding excessive oscillation of the first and screw screws 30, 40, ensuring the displacement stability of the sliding seats 50, and consequently enabling the sliding seats 50 to slide smoothly.
To summarize, the linear table structure in accordance with the present invention comprises: a groove body, a first screw, a second screw, two sliding seats and a connecting calibrating assembly. The first and second screws are connected by the connecting calibrating assembly, the connecting calibrating is used to adjust the pitch error generated on the first and second screws by the sliding seats, thus reducing processing time and cost.
While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.

Claims

1. A linear table structure comprising:

a groove body defined with a receiving space;

a first screw formed on its outer surface with a first threaded section;

a second screw formed on its outer surface with a second threaded section;

two sliding seats each including a base and a nut, the nut being fixed to a side of the base, so that the sliding seats are fixed to the first threaded section of the first screw and the second threaded section of the second screw, respectively, by the nuts;

a connecting calibrating assembly being formed at each end thereof with a positioning portion, one end of the first screw and the second screw are connected to the positioning portions of the connecting calibrating assembly, respectively, the other end of the first screw and the second screw are pivotally disposed in the receiving space of the groove body, the sliding seats utilize the positioning portion of the connecting calibrating assembly to do tension adjustment, thus rotating the first and second screws to adjust pitch error of the sliding seats.

2. The linear table structure as claimed in claim 1, wherein the first screw further includes a first pivot portion and a first connecting portion, the first pivot portion is formed at one end of the first screw, and the first connecting portion is formed at the other end of the first screw;

the second screw further includes a second pivot portion and a second connecting portion, the second pivot portion is formed at one end of the second screw, and the second connecting portion is formed at the other end of the second screw, the first connecting portion of the first screw and the second connecting portion of the second screw are connected to the positioning portion of the connecting calibrating assembly, the first pivot portion of the first screw and the second pivot portion of the second screw are pivotally disposed on an inner surface of both sides of the groove body, so that the first and second screws are disposed in the receiving space of the groove body.

3. The linear table structure as claimed in claim 2, wherein the positioning portions includes an inserting groove, a positioning hole, and a restricting member;

the inserting groove is axially defined in the positioning portion for insertion of the first connecting portion of the first screw and the second connecting portion of the second screw, respectively;

the positioning hole formed with inner threads is radially defined in an outer surface of the positioning portion and is in communication with the inserting groove; and

the restricting member formed with outer threads is pressed against the first connecting section of the first screw and the second connecting section of the second screw by screwing through positioning hole.

4. The linear table structure as claimed in claim 3, wherein an assistant member is pivotally mounted on the first threaded portion of the screw and located beside the first pivot connection to form a single support point on the groove body.

5. The linear table structure as claimed in claim 3, wherein an assistant member is pivotally mounted on the second threaded portion of the second screw and located beside the second pivot portion to form a single support point on the groove body.

6. The linear table structure as claimed in claim 3, wherein an assistant member is mounted on each of the first threaded portion of the screw and the second threaded portion of the second screw located beside the first and second pivot portions.

7. The linear table structure as claimed in claim 3 further comprising an assistant member, and the assistant member is a bearing.

8. The linear table structure as claimed in claim 3, wherein the connecting calibrating assembly further includes a C-shaped retainer, a pulling member, a pivot, a screw, and a nut, the C-shaped retainer is formed at either end of the connecting calibrating assembly for insertion of the first and second screws, respectively, one end of the pulling member is pivotally connected at one end of the screw of the connecting calibrating assembly by the pivot, the screw of the connecting calibrating assembly is inserted through both ends of the C-shaped retainer, and the pulling member is disposed on the C-shaped retainer, one end of the screw of the connecting calibrating assembly is exposed out of the C-shaped retainer so as to screw with the nut, such that both ends of the C-shaped retainer are limited by the pulling member and the nut.

9. The linear table structure as claimed in claim 8, wherein an assistant member is pivotally mounted on the first threaded portion of the screw and located beside the first pivot connection to form a single support point on the groove body.

10. The linear table structure as claimed in claim 8, wherein an assistant member is pivotally mounted on the second threaded portion of the second screw and located beside the second pivot portion to form a single support point on the groove body.

11. The linear table structure as claimed in claim 8, wherein an assistant member is mounted on each of the first threaded portion of the screw and the second threaded portion of the second screw located beside the first and second pivot portions.

12. The linear table structure as claimed in claim 8 further comprising an assistant member, and the assistant member is a bearing.