U.S. patent application number 10/392974 was filed with the patent office on 2003-10-02 for sealing structure.
This patent application is currently assigned to MORI SEIKI CO., LTD.. Invention is credited to Fujii, Takeshi, Kojo, Koichi.
Application Number | 20030183635 10/392974 |
Document ID | / |
Family ID | 28035851 |
Filed Date | 2003-10-02 |
United States Patent
Application |
20030183635 |
Kind Code |
A1 |
Fujii, Takeshi ; et
al. |
October 2, 2003 |
Sealing structure
Abstract
In a vertical machining center, side covers (22) are provided
upright on a saddle on opposite sides of a column. The side covers
(22) each have a surface having a fitting groove (22c) defined
between an open/close door (22b) and an inspection window (22a) of
a rhomboidal shape having anteroposteriorly inclined longitudinal
edges. A front cover (25) is attached to the column. Elongate seal
members (27) are respectively provided along opposite side edges of
the front cover (25) as vertically extending in sliding contact
with the surfaces of the side covers (22) for closing small gaps
defined between the side edges of the front cover (25) and the
surfaces of the side covers (22).
Inventors: |
Fujii, Takeshi;
(Yamatokoriyama-shi, JP) ; Kojo, Koichi;
(Yamatokoriyama-shi, JP) |
Correspondence
Address: |
ARMSTRONG,WESTERMAN & HATTORI, LLP
1725 K STREET, NW
SUITE 1000
WASHINGTON
DC
20006
US
|
Assignee: |
MORI SEIKI CO., LTD.
Yamatokoriyama-shi
JP
|
Family ID: |
28035851 |
Appl. No.: |
10/392974 |
Filed: |
March 21, 2003 |
Current U.S.
Class: |
220/345.1 ;
220/345.6; 409/134 |
Current CPC
Class: |
B23Q 11/0825 20130101;
B23Q 11/085 20130101; Y10T 409/30392 20150115 |
Class at
Publication: |
220/345.1 ;
220/345.6 |
International
Class: |
B65D 043/12; B65D
043/20 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 28, 2002 |
JP |
2002-090174 |
Claims
What is claimed is:
1. A sealing structure comprising: an object having a surface
having a thin groove; a member movable on the surface of the object
with a gap defined between the movable member and the surface of
the object; and a seal member attached to the movable member and
having a flexible edge portion kept in sliding contact with the
surface of the object for closing the gap by the flexible edge
portion; wherein the seal member, which is moved in sliding contact
with the surface of the object as the movable member is moved, is
disposed as intersecting the thin groove present in the surface of
the object.
2. A sealing structure for a machine tool comprising: a saddle
movable laterally on a bed; a column movable back and forth on the
saddle; a front cover attached to the column as covering a front
surface of the column; a side cover having a surface having a thin
groove, and provided upright on the saddle along a direction of
movement of the column with a gap defined between the side cover
and a side edge of the front cover; and a seal member attached to
the front cover and having a flexible edge portion kept in sliding
contact with the surface of the side cover for closing the gap by
the flexible edge portion; wherein the seal member, which is moved
in sliding contact with the surface of the side cover as the column
is moved, is disposed as intersecting the thin groove present in
the surface of the side cover.
3. A sealing structure as set forth in claim 2, wherein the side
cover has an inspection window, wherein an open/close door having a
slightly smaller size than the inspection window is removably
fitted in the inspection window, wherein the thin groove is a
fitting groove defined when the open/close door is fitted in the
inspection window.
4. A sealing structure as set forth in claim 3, wherein the seal
member extends vertically, wherein the inspection window has a
rhomboidal shape having four edges inclined with respect to a
vertical line.
5. A sealing structure as set forth in claim 3, wherein the seal
member is inclined toward a front or rear side with respect to a
vertical line, wherein the inspection window has a rectangular or
square shape having a pair of vertically extending opposite
edges.
6. A sealing structure as set forth in claim 2, wherein the side
cover comprises a plurality of steel plates combined with each
other with opposed end faces thereof abutting against each other.
wherein the thin groove is an abutment groove defined along a
juncture between the steel plates as extending vertically.
7. A sealing structure as set forth in claim 2, wherein the column
comprises a spindle head movable up and down on the front surface
thereof, wherein the front cover comprises an extendible portion
which extends and contracts in accordance with the up-and-down
movement of the spindle head.
8. A sealing structure as set forth in claim 2, further comprising
cover units provided at laterally opposite ends of the bed, wherein
the cover units respectively accommodate cover sheets which are
wound so as to be paid out as biased in a winding direction,
wherein the cover sheets paid out of the cover units are each
connected to a front edge of the side cover via a cover
connector.
9. A sealing structure as set forth in claim 2, further comprising
an extendible cover attached to a lower edge of the front cover,
the extendible cover being adapted to extend and contract in
accordance with the back-and-forth movement of the column.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a sealing structure for
closing a gap defined between a surface of an object and a member
movable on the surface of the object by a seal member attached to
the movable member in sliding contact with the surface of the
object.
[0003] 2. Description of Related Art
[0004] A machine tool including a plurality of members movable in
different directions (e.g., a machining center having a saddle, a
column and a spindle head which are movable along an X-axis, a
Y-axis and a Z-axis, respectively) generally includes various
covers which are provided to isolate guide ways for guiding the
respective movable members and ball threads for driving the
respective movable members from a machining region for protection
of these members from chips and the like. Some of these covers are
provided in relatively movable manner, so that a gap is defined
therebetween. Therefore, a sealing structure for closing a gap
defined between two associated covers is employed which includes a
seal member (e.g., a lip seal) attached to one of the covers in
sliding contact with a surface of the other cover.
[0005] Since such a cover is provided for isolating the inside of
the machine from the machining region as described above, it is
often necessary to provide an inspection window in the cover for
inspecting the inside of the machine. In general, an open/close
door having a slightly smaller size than the inspection window
provided in the cover and openable for inspection is removably
fitted in the inspection window to close the inspection window.
Therefore, a thin fitting groove is present in the surface of the
cover between the open/close door and the peripheral edge of the
inspection window.
[0006] Where the cover is too large to be formed of a single steel
plate or the like, the cover is formed by combining a plurality of
steel plates with each other with their opposed end faces abutting
against each other. In this case, a thin abutment groove is present
in the large cover along a juncture between the steel plates.
[0007] As shown in FIG. 9, when a seal member (e.g. lip seal) 60 is
slid on a surface of a cover 50 having a thin groove 51 such as the
fitting groove or the abutment groove to pass over the thin groove
51 present in the surface of the cover 50, a flexible edge portion
61 of the seal member 60 kept in press contact with the surface of
the cover may enter the thin groove 51. When the seal member 60 is
repeatedly moved in and out of the thin groove 51, the flexible
edge portion 61 of the seal member 60 is liable to be broken or
deformed. This makes it impossible to keep the seal member 60 into
contact with the surface of the cover, deteriorating the sealing
performance.
[0008] It is therefore an object of the present invention to
provide a sealing structure for closing a gap defined between a
surface of an object and a member movable on the surface of the
object by a seal member attached to the movable member in sliding
contact with the surface of the object, the seal member being
unlikely to enter a thin groove present in the surface of the
object.
SUMMARY OF THE INVENTION
[0009] In accordance with a first aspect of the present invention
to achieve the aforesaid object, there is provided a sealing
structure comprising: an object having a surface having a thin
groove; a member movable on the surface of the object with a gap
defined between the movable member and the surface of the object;
and a seal member attached to the movable member and having a
flexible edge portion kept in sliding contact with the surface of
the object for closing the gap by the flexible edge portion;
wherein the seal member, which is moved in sliding contact with the
surface of the object as the movable member is moved, is disposed
as intersecting the thin groove present in the surface of the
object.
[0010] In this sealing structure, the seal member moved in sliding
contact with the surface of the object is disposed as intersecting
the thin groove present in the surface of the object as described
above. Hence, there is no possibility that the edge portion of the
seal member enters the thin groove when the seal member passes over
the thin groove present in the surface of the object. With this
sealing structure, the breakage or deformation of the seal member
can assuredly be prevented, leading to more reliable sealing
performance.
[0011] Particularly, the present invention may be embodied as a
sealing structure for a machine tool, which comprises a saddle
movable laterally on a bed, a column movable back and forth on the
saddle, a front cover attached to the column as covering a front
surface of the column, a side cover having a surface having a thin
groove and provided upright on the saddle along a direction of
movement of the column with a gap defined between the side cover
and a side edge of the front cover, and a seal member attached to
the front cover and having a flexible edge portion kept in sliding
contact with the surface of the side cover for closing the gap by
the flexible edge portion. In this case, the seal member, which is
moved in sliding contact with the surface of the side cover as the
column is moved, is disposed as intersecting the thin groove
present in the surface of the side cover.
[0012] The foregoing and other objects, features and effects of the
present invention will become more apparent from the following
description of the preferred embodiments with reference to the
attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view illustrating a vertical
machining center which employs a sealing structure according to the
present invention;
[0014] FIG. 2 is a front view illustrating the vertical machining
center;
[0015] FIG. 3 is a schematic side view illustrating a positional
relationship between side covers and a front cover in the vertical
machining center;
[0016] FIG. 4 is a schematic plan view illustrating the positional
relationship between the side covers and the front cover in the
vertical machining center;
[0017] FIG. 5 is a schematic front view illustrating the positional
relationship between the side covers and the front cover in the
vertical machining center;
[0018] FIGS. 6A to 6C are perspective views illustrating the
movement of the front cover relative to the side covers in the
vertical machining center;
[0019] FIG. 7 is a partially enlarged perspective view illustrating
a seal member attached to the front cover;
[0020] FIG. 8 is a diagram illustrating a positional relationship
between the seal member and an inspection window provided in the
side cover, which is observed when the seal member passes over the
inspection window; and
[0021] FIG. 9 is a diagram for explaining a problem associated with
a prior art sealing structure.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Preferred embodiments of the present invention will
hereinafter be described with reference to the drawings. FIGS. 1 to
5 illustrate a vertical machining center 1 which employs a sealing
structure according to the present invention. As shown, the
vertical machining center 1 includes a table 12 fixed to a front
portion of a bed 11, a saddle 13 movable laterally of the table 12
(along an X-axis) on guide ways 11a provided on a rear portion of
the bed 11, a column 14 movable back and forth (along a Y-axis) on
guide ways 13a provided on an upper surface of the saddle 13, and a
spindle head 15 movable up and down (along a Z-axis) on guide ways
14a provided on a front surface of the column 14. The spindle head
15 is covered with a head cover 21.
[0023] A pair of side covers 22 each formed of a steel plate are
provided upright on the saddle 13 on opposite sides of the column
14 with respect to the X-axis as extending along the Y-axis. As
shown in FIGS. 6A, 6B, 6C and 8, the side covers 22 are each formed
with a rhomboidal inspection window 22a having anteroposteriorly
inclined longitudinal edges. An open/close door 22b having a
slightly smaller size than the inspection window 22a and openable
for inspection is removably fitted in the inspection window 22a.
Therefore, a fitting groove 22c is present in the surface of the
side cover 22 between the open/close door 22b and the peripheral
edge of the inspection window 22a.
[0024] Further, a pair of cover units 23 are provided at opposite
ends of the bed 11 with respect to the X-axis. The cover units 23
respectively accommodate cover sheets 23a which are wound to be
paid out as biased in a winding direction. The cover sheets 23a
paid out of the respective cover units 23 are connected to front
edges of the paired side covers 22 via cover connectors 24 each
formed of a steel plate.
[0025] Therefore, a region where the saddle guide ways 11a and a
ball thread (not shown) as a saddle driving mechanism are disposed
is completely isolated from a machining region by the cover sheets
23a paid out of the cover units 23, the cover connectors 24 and the
side covers 22, whereby the saddle guide ways and the ball thread
are protected from chips and the like.
[0026] A front cover 25 for covering the spindle head guide ways
14a and a ball thread (not shown) as a spindle head driving
mechanism is attached to the column 14 below the head cover 21
surrounding the spindle head 15. The front cover 25 includes an
extendible portion 25a which extends and contracts in accordance
with the up-and-down movement of the spindle head 15.
[0027] An extendible cover 26 for covering the column guide way 13a
and a ball thread (not shown) as a column moving mechanism is
attached to a lower edge of the front cover 25. The extendible
cover 26 extends and contracts in accordance with the
back-and-forth movement of the column 14 (see FIGS. 6A, 6B and
6C).
[0028] As shown in FIGS. 6A, 6B and 6C, small gaps are defined
between surfaces of the side covers 22 and opposite side edges of
the front cover 25 movable back and forth along the Y-axis together
with the column 14. For closing the gaps, elongate seal members 27
are respectively attached to the opposite side edges of the front
cover 25 as extending perpendicularly to the Y-axis. In FIGS. 6A,
6B and 6C, structural elements such as the column 14, the spindle
head 15 and the head cover 21 are not shown for easier
understanding of the movement of the front cover 25 relative to the
side covers 22.
[0029] As shown in FIG. 7, the seal members 27 each include a
generally rigid support portion 27a supported by the associated
side edge of the front cover 25, and a lip-shaped flexible edge
portion 27b connected to the support portion 27a. The edge portion
27b projecting from the support portion 27a at a predetermined
angle is kept in press contact with the surface of the side cover
22. Therefore, the seal member 27 is slidable on the surface of the
side cover 22 as the front cover 25 is moved back and forth along
the Y-axis together with the column 14.
[0030] As described above, the fitting groove 22c defined between
the peripheral edge of the inspection window 22a and the open/close
door 22b fitted in the inspection window 22a is present in the
surface of the side cover 22 on which the seal member 27 is slide.
However, the inspection window 22a has a rhomboidal shape having
anteroposteriorly inclined longitudinal edges as described above,
whereas the seal member 27 is supported by the front cover 25 as
extending perpendicularly to the Y-axis. In the sealing structure,
therefore, the edge of the seal member 27 intersects parts of the
fitting groove 22c extending along the inclined longitudinal edges
of the inspection window 22a as shown in FIG. 8, when the seal
member 27 passes over the inspection window 22a.
[0031] Therefore, there is no possibility that the flexible edge
portion 27b of the seal member 27 enters the parts of the fitting
groove extending along the inclined longitudinal edges of the
inspection window 22a when the seal member 27 passes over the
inspection window 22a. Therefore, the breakage or deformation of
the flexible edge portion 27b of the seal member 27 can assuredly
be prevented, leading to more reliable sealing performance.
[0032] In the embodiment described above, the inspection window 22a
has a rhomboidal shape having anteroposteriorly inclined
longitudinal edges, so that the seal member 27 attached to the
front cover 25 as extending perpendicularly to the Y-axis
intersects the fitting groove 22c present in the surface of the
side cover 22 between the peripheral edge of the inspection window
22a and the open/close door 22b. However, the present invention is
not limited to this arrangement. For example, the inspection window
provided in the side cover 22 may have a rectangular or square
shape having a pair of vertically extending opposite edges. In this
case, the seal member 27 attached to the front cover 22 is inclined
with respect to the Y-axis. This arrangement also allows the seal
member 27 to intersect the fitting groove present in the surface of
the side cover 22.
[0033] Further, the embodiment described above is directed to the
case where the fitting groove is present between the peripheral
edge of the inspection window 22a and the open/close door 22b in
the surface of the side cover 22 on which the seal member 27 is
slid. However, the present invention is not limited to the case.
The present invention is also applicable to a case, for example,
where the side cover is formed by combining a plurality of steel
plates with each other with their end faces abutting against each
other and, hence, has an abutment groove along a juncture between
the steel plates. Even in this case, the same effect can be
provided by allowing the seal member to intersect the abutment
groove.
[0034] Further, the embodiment described above is directed to the
vertical machining center 1 employing the sealing structure in
which the gaps defined between the surfaces of the side covers 22
and the side edges of the front cover 25 are closed by the seal
members 27 respectively attached to the side edges of the front
cover 25. However, the present invention is not limited to this
sealing structure, but is applicable to various types of sealing
structures for closing a gap defined between a surface of an object
having a thin groove such as a fitting groove or an abutment groove
and a member movable on the surface of the object by a seal member
attached to the movable member in sliding contact with the surface
of the object.
[0035] While the present invention has been described in detail by
way of the embodiment thereof, it should be understood that the
foregoing disclosure is merely illustrative of the technical
principles of the present invention but not limitative of the same.
The spirit and scope of the present invention are to be limited
only by the appended claims.
* * * * *