Patent Application
20050253343
The claimed invention relates generally to the field of housing structures and more particularly, but not by way of limitation, to an apparatus and method for forming a housing seal.
Disc drives are digital data storage devices which store and retrieve large amounts of user data in a fast and efficient manner. The data are magnetically recorded on the surfaces of one or more data storage discs (media) affixed to a spindle motor for rotation at a constant high speed.
An array of vertically aligned data transducing heads are controllably positioned by an actuator to read data from and write data to tracks defined on the recording surfaces. An actuator motor rotates the actuator to move the heads across the disc surfaces. The heads are configured to be hydrodynamically supported adjacent the disc surfaces by fluidic pressures established by the high speed rotation of the discs.
It is generally desirable to enclose the heads and recording media in a sealed housing to protect these components from the deleterious effects of fluid-borne contaminants from the surrounding atmosphere. Some device designers have proposed hermetically sealed designs that contain a lower density atmosphere within the housing, such as an inert gas (helium, etc.), to reduce windage and vibration effects and achieve higher levels of operational performance.
With the continued demand for higher performance data storage devices, there remains a continual need for improved housing seal configurations. It is to these and other improvements that the claimed invention is generally directed.
As embodied herein and as claimed below, the present invention is generally directed to an apparatus and method for sealing a housing.
In accordance with some preferred embodiments, the apparatus comprises opposing first and second housing members, the first member having a groove formed by opposing sidewalls and a recessed surface at a distal extent of the groove.
A sealing material spans the groove so that, upon compression of the material between said members, a unitary channel is formed by a medial portion of the sealing material, the opposing sidewalls and the recessed surface.
The groove preferably extends adjacent a peripheral edge of the first housing member so that the sealing material and the first and second housing members form an enclosed, sealed housing. The channel preferably entraps a fluid, such as air, which operates as a compliant member to support the sealing member.
Preferably, the first housing member comprises a substantially planar first surface into which the groove partially extends. The second housing member comprises a substantially planar second surface, and the sealing material is respectively compressed between the first and second surfaces on opposing sides of the groove.
In accordance with further preferred embodiments, the method comprises providing opposing first and second housing members, the first housing member having a groove formed by opposing sidewalls and a recessed surface at a distal extent.
The method further comprises compressing a sealing material between the first and second housing members, the sealing member spanning the groove so that a unitary channel is formed by a medial portion of the sealing material, the opposing sidewalls and the recessed surface.
The compressing step preferably entraps a fluid within said channel to provide compliant support of the sealing material. The method further preferably comprises applying the sealing material as a bead to a selected one of the first and second housing members in alignment with the groove to form a form in place gasket (FIPG).
The providing step preferably comprises supplying the first housing member with a substantially planar first surface into which the groove extends and the second housing member with a substantially planar second surface, and the compressing step further preferably comprises respectively compressing the sealing material between the first and second surfaces on opposing sides of the groove.
These and various other features and advantages which characterize the claimed invention will become apparent upon reading the following detailed description and upon reviewing the associated drawings.
While the claimed invention has utility in any number of different applications,
The sealed housing provides a controlled interior environment for various constituent components of the device 100, including a spindle motor 106 which rotates a number of data recording discs 108, and an actuator 110 which supports a corresponding array of data transducing heads 112 adjacent the disc surfaces.
The actuator 110 is controllably positioned by a voice coil motor (VCM) 114 which aligns the heads 112 with tracks (not shown) defined on the disc surfaces. A flex circuit assembly 116 provides electrical communication paths between the actuator 110 and control electronics supported on a printed circuit board assembly (PCBA) 118 mounted to the underside of the base deck 102.
Of particular interest to the present discussion is the manner in which the top cover 104 mates with the base deck 102 to form the sealed housing. A first preferred embodiment is shown in
The groove 122 circumferentially extends adjacent a peripheral edge 126 of the top cover 104, as depicted in
A suitable sealing material 128 spans the groove 122. The sealing material preferably comprises a bead of viscous elastomeric material that is controllably applied to the top cover 104 to provide a form in place gasket (FIPG). Other sealing materials and configurations can be used, however, such as a preformed gasket having a selected cross-sectional shape, such as circular (i.e., a hollow or solid o-ring).
The base deck 102 in
Upon compression of the sealing material 128, a portion of the material partially extends into the groove 122, leaving a gap between the sealing material 128 and the recessed surface 125. A unitary channel 138 is accordingly formed by a medial portion 140 of the sealing material, the opposing sidewalls 124 and the recessed surface 125, said channel extending along the length of the groove. The channel 138 preferably serves to entrap a fluid (such as air) to compliantly support the sealing material 128.
It will be noted that the various preferred embodiments presented herein provide certain advantages over the prior art. The embodiments are easily manufactured and accept tolerance variations within ranges that are readily achievable using standard manufacturing processes.
The entrapped fluid in the channel operates as a compliant member that supports the sealing material so that lower compression forces can be utilized during the clamping of the top cover to the base deck. This eliminates the need for the addition of expensive structural members or extra material as in prior art designs.
Also, the need to machine or otherwise precision form the path for a preformed sealing gasket (such as in the base deck) can be eliminated, as well as the sorting of various housing members during the manufacturing process to locate base deck/top cover pairs with desired dimensions and/or tolerances.
It will now be understood that the present invention (as embodied herein and as claimed below is generally directed to an apparatus and method for sealing a housing.
In accordance with some preferred embodiments, the apparatus comprises opposing first and second housing members (such as 102 and 104), said first member having a groove (such as 122) formed by opposing sidewalls (such as 124) and a recessed surface (such as 125) at a distal extent (such as distance D).
A sealing material (such as 128) spans the groove so that, upon compression of the material between said members, a unitary channel (such as 138) is formed by a medial portion (such as 140) of the sealing material, the opposing sidewalls (such as 125) and the recessed surface (such as 124).
The groove preferably extends adjacent a peripheral edge (such as 126) of the first housing member so that the sealing material and the first and second housing members form an enclosed, sealed housing. The channel preferably entraps a fluid, such as air, which operates as a compliant member to support the sealing member.
Preferably, the first housing member comprises a substantially planar first surface (such as 120) into which the groove partially extends. The second housing member comprises a substantially planar second surface (such as 130), and the sealing material is respectively compressed between the first and second surfaces on opposing sides of the groove.
In accordance with further preferred embodiments, the method comprises providing opposing first and second housing members (such as 102, 104), the first housing member having a groove (such as 122) formed by opposing sidewalls (such as 124) and a recessed surface (such as 125) at a distal extent (such as distance D).
The method further-comprises compressing a sealing material (such as 128) between the first and second housing members, the sealing member spanning the groove so that a unitary channel (such as 138) is formed by a medial portion (such as 140) of the sealing material, the opposing sidewalls (such as 124) and the recessed surface (such as 125).
The compressing step preferably entraps a fluid within said channel to provide compliant support of the sealing material. The method further preferably comprises applying the sealing material as a bead to a selected one of the first and second housing members in alignment with the groove to form a form in place gasket (FIPG).
The providing step preferably comprises supplying the first housing member with a substantially planar first surface (such as 120) into which the groove extends and the second housing member with a substantially planar second surface (130), and the compressing step preferably comprises respectively compressing the sealing material between the first and second surfaces on opposing sides of the groove.
For purposes of the appended claims, the term “unitary channel” will be defined consistent with the foregoing discussion as a single, continuous channel that extends along the length of the groove (such as 122) as a result of noncontact between the sealing material (such as 128) and the recessed surface (such as 125).
The term “distal extent” will be defined consistent with the foregoing discussion to describe a maximum depth distance of the gap (such as the distance D shown in
The recited “first means” will be understood to correspond to at least the sealing material 128, the groove 122 and the unitary channel 138, as shown in
It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments of the invention, this detailed description is illustrative only, and changes may be made in detail, especially in matters of structure and arrangements of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. For example, the particular elements may vary depending on the particular application of the housing without departing from the spirit and scope of the present invention.
In addition, although the embodiments described herein are directed to the sealing of a data storage device housing, it will be appreciated by those skilled in the art that the claimed subject matter is not so limited, but rather extends to any number of different housing applications.
