Magnetic head arm of hard disk drive

Abstract

The utility model discloses a magnetic head arm of a hard disk drive, which comprises a magnetic head cantilever and a driving arm which are integrally connected. A pivot hole is formed in the joint of the magnetic head cantilever and the driving arm and is used for mounting a rotating shaft; a containing groove is formed in the end, away from the pivot hole, of the driving arm and used for installing a voice coil. A limiting protruding block is arranged on one side of the driving arm and comprises a first arc section, a second arc section and a limiting section, and the first arc section, the second arc section and the limiting section are sequentially connected. According to the technical scheme, the limiting protruding block is arranged on the driving arm, the first arc section and the second arc section on the limiting protruding block are connected with the limiting section, the limiting column is provided with the matched contact faces, and when abnormal conditions such as sudden power failure or mechanical impact or control failure happen, the magnetic head arm collides with the limiting column, the magnetic head arm can be prevented from being damaged. The position where the limiting protruding block collides with the limiting column is in surface contact, contact is more stable, loads can be better dispersed through surface contact, and mechanical damage caused by local overload is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of hard disk drives, in particular to a magnetic head arm of a hard disk drive. Background Art

[0002] The head arm, also known as the head drive arm, is a component in the hard disk drive. It is mainly used to move the head to the read and write position on the disk surface in order to read and write data. During the operation of the hard disk, the head arm is driven by the voice coil motor to move precisely above the high-speed rotating disk to read and write data. When the hard disk is not working, the head stays in the start-stop area of ​​the disk. The start-stop area is a special area that does not store any data. When the hard disk is not working or the disk does not reach the predetermined rotation speed, the head will be moved to this area for parking to prevent contact between the head and the disk, thereby protecting the hard disk from damage.

[0003] In the prior art, in order to protect the magnetic head from exceeding the working range, the hard disk is usually equipped with a limit post, which is used as a physical barrier to limit the maximum stroke of the magnetic head arm. However, in abnormal situations such as sudden power failure, mechanical shock or control system failure, there is a risk of unexpected collision between the magnetic head arm and the limit post. When the magnetic head arm collides with the limit post under the above abnormal circumstances, the contact between the limit post and the magnetic head arm is usually that the side of the magnetic head arm is in linear contact with the limit post in the thickness direction. During the collision process, since the linear contact area between the magnetic head arm and the limit post in the thickness direction is small, the extrusion force is relatively concentrated, and the stress at the collision site is high, which can easily cause mechanical damage, thereby affecting the service life of the magnetic head arm.

[0004] To this end, the present application aims to propose a magnetic head arm for a hard disk drive, aiming to solve the above-mentioned problems. Utility Model Content

[0005] The main purpose of the utility model is to provide a head arm for a hard disk drive, aiming to solve the technical problem in the prior art that, due to the small linear contact area between the head arm and the limit post in the thickness direction, when a collision occurs under abnormal circumstances, the stress is more concentrated, which is easy to cause mechanical damage and thus affects the service life of the head arm.

[0006] In order to achieve the above-mentioned purpose of the utility model, the utility model proposes a head arm of a hard disk drive, including a head cantilever and a driving arm, the head cantilever and the driving arm are connected as one body; a pivot hole is provided at the connection between the head cantilever and the driving arm, and the pivot hole is used to install a rotating shaft; a receiving groove is provided at one end of the driving arm away from the pivot hole, and the receiving groove is used to install a voice coil; a limiting protrusion is provided on one side of the driving arm, and the limiting protrusion includes a first arc segment, a second arc segment and a limiting segment with a concave surface facing the receiving groove, and the first arc segment, the second arc segment and the limiting segment are connected in sequence.

[0007] Furthermore, a first mounting portion is provided at one end of the head suspension away from the driving arm, and the first mounting portion is used for mounting the magnetic head or the flexible arm.

[0008] Furthermore, the first mounting portion is formed by inward depression of one or both sides of the end of the magnetic head arm.

[0009] Furthermore, a second mounting portion is provided on a side of the head cantilever away from the limiting protrusion, and the second mounting portion is used for mounting a flexible circuit board.

[0010] Furthermore, a first limiting groove is provided on the driving arm away from a side surface of the limiting protrusion and close to an end of the second mounting portion.

[0011] Furthermore, a second limiting groove is provided on the driving arm away from a side surface of the limiting protrusion and away from an end of the second mounting portion.

[0012] Furthermore, a convex rib is arranged inside the pivot hole.

[0013] Furthermore, the head suspension is provided with a process hole, and the process hole is provided between the pivot hole and the first mounting portion.

[0014] Furthermore, the surfaces of the process hole close to one end of the pivot hole and one end of the first mounting portion are arc surfaces, and the inner diameter of the arc surface close to one end of the pivot hole is larger than the inner diameter of the arc surface close to one end of the first mounting portion.

[0015] Furthermore, the magnetic head arm is made of aluminum.

[0016] Beneficial effects:

[0017] Compared with the prior art, a magnetic head arm of a hard disk drive in an embodiment of the present application comprises a magnetic head cantilever and a driving arm, wherein the magnetic head cantilever and the driving arm are connected as one body; a pivot hole is provided at the connection between the magnetic head cantilever and the driving arm, wherein the pivot hole is used to install a rotating shaft; a receiving groove is provided at one end of the driving arm away from the pivot hole, wherein the receiving groove is used to install a voice coil; a limiting protrusion is provided on one side of the driving arm, wherein the limiting protrusion comprises a first arc segment, a second arc segment and a limiting segment with a concave surface facing the containing groove, wherein the first arc segment, the second arc segment and the limiting segment are connected in sequence. The technical solution is provided with a limiting protrusion on the driving arm, wherein the first arc segment, the second arc segment and the limiting segment on the limiting protrusion are connected, and the limiting column is provided with a matching contact surface. When an abnormal situation such as sudden power failure, mechanical shock or control failure occurs, resulting in a collision between the magnetic head arm and the limiting column, the position where the limiting protrusion collides with the limiting column is surface contact, which is more stable during contact. Surface contact can better disperse the load and reduce mechanical damage caused by local overload. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the planar structure of an existing magnetic head arm;

[0019] Figure 2 A schematic diagram of the three-dimensional structure of a magnetic head arm according to an embodiment of the utility model;

[0020] Figure 3 A schematic diagram of the three-dimensional structure of a magnetic head arm according to another embodiment of the utility model;

[0021] Figure 4 The figure is a schematic diagram of the planar structure of a magnetic head arm according to an embodiment of the utility model.

[0022] in:

[0023] 1. head arm; 10. head cantilever; 100. pivot hole; 1000. convex rib; 101. first mounting portion; 102. second mounting portion; 103. process hole; 11. drive arm; 110. accommodating groove; 111. limiting protrusion; 1110. first arc segment; 1111. second arc segment; 1112. limiting segment; 112. first limiting groove; 113. second limiting groove.

[0024] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0025] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0027] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0028] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] A disk drive is a computer storage device that can read data from or write data to disk storage media (such as hard disks, floppy disks, etc.). When reading data, the disk drive uses a magnetic head to sense magnetic changes in the magnetic coating on the disk surface. The disk rotates at high speed driven by a voice coil motor, and the magnetic head is suspended at a very small distance (usually at the nanometer level) above the disk surface. As the disk rotates, the magnetic head can detect changes in magnetic flux on the disk surface, which represent the data stored on the disk. The magnetic head converts the detected magnetic signal into an electrical signal, which is then processed by a series of circuits and finally transmitted to other parts of the computer, such as memory or the central processing unit (CPU). When writing data, the computer sends the data to be stored to the disk drive in the form of electrical signals. The circuits in the disk drive convert these electrical signals into changes in the magnetic field that the magnetic head can generate. Based on these signals, the magnetic head generates corresponding magnetic changes in the magnetic coating on the disk surface, thereby recording the data on the disk in a magnetic form.

[0030] In a disk drive, data reading or writing requires the use of a head assembly, which usually includes a read / write head, a head arm, a voice coil motor, and a preamplifier. One end of the head arm is connected to the head, and the other end is connected to the voice coil motor. Through a driving device such as a voice coil motor, the head can be accurately moved to a specific track and sector position on the disk surface when the disk rotates at high speed. The voice coil motor consists of a rigid magnetic flux loop, a permanent magnet, a motion mechanism, and a voice coil. The permanent magnet is embedded in the rigid magnetic flux loop to form a uniform magnetic field in space, and the voice coil is arranged in the receiving groove of the driving arm. The driving principle is as follows: the energized voice coil is acted upon by the Ampere force in the magnetic field, and the Ampere force drives the head arm to swing around the rotating shaft. The magnitude of the current can change the magnitude of the Ampere force, thereby controlling the speed of the voice coil movement. The direction of the current can change the direction of the Ampere force, thereby controlling the direction of the voice coil movement. As the core mechanical component in the disk drive, the head arm provides mechanical support for the head. The stability of its performance plays an important role in the accuracy and efficiency of data reading and writing operations.

[0031] For example, the existing design of the magnetic head arm can be found in Figure 1 In the existing design of hard disk, the limit post for limiting the maximum travel of the head arm is usually a circular post, which usually contacts the side of the other end of the head arm when one end of the head enters the start-stop zone, such as Figure 1 As shown, since the side surface is an arc segment with a concave surface facing outward, when it contacts the circular limit post, the contact in the thickness direction of the head arm is a line contact, and the contact area is relatively small. When abnormal situations such as sudden power failure, mechanical shock, or control system failure occur, the head arm is at risk of colliding with the limit post. For example, if the head arm is moving rapidly toward the start-stop area, and the power is suddenly cut off when the head arm approaches the circular limit post, due to inertia, the head arm will continue to move in the direction of movement for a period of time, resulting in a collision with the circular limit post. Since the contact in the thickness direction of the head arm is a line contact, the contact area is relatively small, and the pressure is relatively concentrated during the collision, which can easily cause mechanical damage.

[0032] In order to solve the technical problem in the above-mentioned prior art that, due to the small linear contact area between the magnetic head arm and the limiting column in the thickness direction, when a collision occurs under abnormal circumstances, the stress is concentrated, which is easy to cause mechanical damage and thus affects the service life of the magnetic head arm, the embodiment of the present application provides a magnetic head arm for a hard disk drive, and the technical solution is provided by setting a limiting protrusion 111 on the driving arm 11, and the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 on the limiting protrusion 111 are connected, and the limiting column is provided with an adaptive contact surface. When an abnormal situation such as sudden power failure, mechanical shock or control failure occurs, causing the magnetic head arm to collide with the limiting column, the position where the limiting protrusion 111 collides with the limiting column is surface contact, which is more stable during contact. Surface contact can better disperse the load and reduce mechanical damage caused by local overload. The magnetic head arm in the embodiment of the present application will be described in detail below in conjunction with the accompanying drawings.

[0033] See also Figures 2 to 4 In the present embodiment, a head arm 1 of a hard disk drive is provided, comprising a head suspension 10 and a driving arm 11, wherein the head suspension 10 and the driving arm 11 are integrally connected; a pivot hole 100 is provided at the connection between the head suspension 10 and the driving arm 11, wherein the pivot hole 100 is used to install a rotating shaft; an accommodating groove 110 is provided at one end of the driving arm 11 away from the pivot hole 100, wherein the accommodating groove 110 is used to install a voice coil; a limiting protrusion 111 is provided on one side of the driving arm 11, wherein the limiting protrusion 111 comprises a first arc segment 1110, a second arc segment 1111 and a limiting segment 1112 with a concave surface facing the accommodating groove 110, wherein the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 are connected in sequence.

[0034] In this embodiment, the magnetic head can be directly mounted on the end of the magnetic head suspension 10 away from the receiving slot to support and move the magnetic head to the correct position on the disk surface for data reading and writing. It should be noted that the hard disk will generate a certain degree of vibration during operation, especially when the voice coil motor drives the disk to rotate at high speed and the driving arm 11 seeks quickly. Therefore, the magnetic head can also be mounted on the end away from the receiving slot through a flexible arm. The flexible arm can play a role of buffering and shock absorption. It can absorb these vibrations and prevent the vibration from being transmitted to the magnetic head. The driving arm 11 is used to connect the magnetic head suspension 10 and the voice coil motor to transmit the movement of the voice coil motor to the magnetic head suspension 10. Specifically, the driving arm 11 is connected to the voice coil motor through the pivot hole 100 and the rotating shaft, thereby allowing the magnetic head arm 1 to rotate around the rotating shaft to realize the movement of the magnetic head on the disk surface. The receiving slot 110 is used to install the voice coil coil, wherein the voice coil coil is a part of the voice coil motor. The voice coil coil is subjected to the Ampere force in the magnetic field, and the moving direction and speed of the magnetic head arm 1 are controlled by changing the direction and magnitude of the current. When the hard disk is not working, the magnetic head stays in the start-stop area of ​​the disk. The limiting protrusion 111 can ensure that the magnetic head is correctly parked in the start-stop area to prevent the magnetic head from sliding to the data area when the hard disk is started or stopped, causing data damage.

[0035] In the above embodiment, the limiting protrusion 111 is arranged in a manner that the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 are connected, mainly because the area of ​​the first arc segment 1110 and the second arc segment 1111 is larger than the area of ​​the inclined surface or the single curved surface under the same conditions, and the contact surface is larger when it is used to contact with the corresponding matching limiting column. Compared with the prior art, the technical solution of the present application is provided with a limiting protrusion 111 on the driving arm 11, and the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 on the limiting protrusion 111 are connected, and the limiting column is provided with a matching contact surface. When an abnormal situation such as sudden power failure, mechanical shock or control failure occurs, causing the magnetic head arm 1 to collide with the limiting column, the position where the limiting protrusion 111 collides with the limiting column is surface contact, which is more stable during contact. Surface contact can better disperse the load and reduce mechanical damage caused by local overload.

[0036] See also Figures 2 to 4 In one embodiment, the end of the head suspension 10 away from the driving arm 11 is provided with a first mounting portion 101, and the first mounting portion 101 is used to mount a head or a flexible arm. The first mounting portion 101 is formed by inward depression of one or both sides of the end of the head arm 1.

[0037] In the present embodiment, the installation of the magnetic head or the flexible arm on the magnetic head cantilever 10 is realized through the first installation part 101. The first installation part 101 is formed by an inward depression on one or both sides of the end of the magnetic head arm 1, providing a stable installation platform for fixing the magnetic head or the flexible arm. Specifically, the flexible arm can be fixed to the first installation part 101 by glue or adhesive, or by welding, or a mounting hole can be set on the first installation part 101, and the flexible arm can be fixedly connected by the mounting hole and bolts. Similarly, the magnetic head can also be fixed in the above manner. It can be understood that when the first installation part 101 is used to install the flexible arm, the magnetic head is installed at the other end of the flexible arm, and the design of the flexible arm enables it to withstand certain bending and twisting while maintaining a precise distance between the magnetic head and the disk surface.

[0038] See also Figures 2 to 4 In one embodiment, a second mounting portion 102 is disposed on a side of the head suspension 10 away from the limiting protrusion 111 , and the second mounting portion 102 is used for mounting a flexible circuit board.

[0039] In this embodiment, the flexible circuit board connects the magnetic head on the magnetic head arm 1 with the control unit of the hard disk through a line. The flexible circuit board not only transmits data signals, but also transmits control signals, such as magnetic head positioning instructions and feedback signals. The specific control process is as follows: the hard disk control unit calculates the track to which the magnetic head needs to move according to the required data position and generates a positioning instruction. The control unit sends the positioning instruction to the preamplifier through the flexible circuit board. After receiving the instruction from the control unit, the preamplifier amplifies it and converts it into a current signal for driving the voice coil motor. The voice coil motor generates a corresponding Ampere force according to the current signal provided by the preamplifier, drives the magnetic head arm 1 to move, and the magnetic head arm 1 rotates around the shaft to move the magnetic head above the target track. The position sensor (such as a servo sensor) of the magnetic head arm 1 monitors the position of the magnetic head in real time and feeds back the position information to the control unit.

[0040] In the above embodiment, the second mounting portion 102 provides a mounting position for the flexible circuit board, ensuring that the flexible circuit board can normally provide electrical connection, transmit control signals and data, so that the magnetic head arm 1 can respond to the instructions of the hard disk control unit. It can be understood that when multiple magnetic head arms are arranged in the shaft, the second mounting portions 102 of the multiple magnetic head arms together constitute the mounting space of the flexible circuit board for the installation of the flexible circuit board.

[0041] See also Figures 2 to 4 In one embodiment, a first limiting groove 112 is provided on a side of the driving arm 11 away from the limiting protrusion 111 and close to an end of the second mounting portion 102 .

[0042] In this embodiment, the first limit groove 112 is used to limit the swing amplitude of the driving arm 11. Specifically, under the action of the voice coil motor, the driving arm 11 moves in a manner of swinging around the rotating shaft, and the limit protrusion 111 limits the maximum swing position and the parking position of one side of the driving arm 11. Therefore, the first limit groove 112 is used to limit the position of the swing amplitude of the other side of the driving arm 11 to prevent the driving arm 11 from exceeding the designed swing range under abnormal circumstances. Specifically, as Figure 4 As shown, the first limiting groove 112 is an arc with the concave surface facing inward, which can cooperate with the arc-shaped limiting column with the concave surface facing outward. When the arc-shaped first limiting groove 112 contacts the limiting column, the contact area between the inclined surface and the arc-shaped limiting column with the concave surface facing outward in the prior art is larger, thereby reducing stress concentration, thereby protecting the head and the disk surface and extending the service life of the hard disk.

[0043] See also Figures 2 to 4 In one embodiment, a second limiting groove 113 is provided on a side of the driving arm 11 away from the limiting protrusion 111 and away from an end of the second mounting portion 102 .

[0044] In this embodiment, the second limiting groove 113 has the same function as the first limiting groove 112, which is used to limit the swing amplitude of the driving arm 11. It can be understood that the purpose of setting the second limiting groove 113 is to limit the position by the first limiting groove 112 and the second limiting groove 113 at the same time, that is, after the driving arm 11 moves to the position with the largest swing amplitude, the first limiting groove 112 and the second limiting groove 113 contact the corresponding limiting column at the same time. When the first limiting groove 112 and the second limiting groove 113 act at the same time, the contact area can be further increased and the stress concentration can be further reduced. Specifically, the second limiting groove 113 can also be a concave inward arc, which can be adapted to the corresponding limiting column.

[0045] See also Figures 2 to 4 In one embodiment, a rib 1000 is disposed inside the pivot hole 100 .

[0046] In this embodiment, when the magnetic head arm 1 rotates around the shaft, the rib 1000 can prevent the shaft and the driving arm 11 from rotating relative to each other. The presence of the rib 1000 makes the pivot hole 100 more durable and can withstand the repeated stress generated by the magnetic head arm 1 during the read and write operations. At the same time, the rib 1000 can also help fix and align the shaft, and it provides a clear reference point, making the installation of the shaft more accurate and consistent.

[0047] See also Figures 2 to 4 In one embodiment, the head suspension 10 is provided with a process hole 103 , and the process hole 103 is provided between the pivot hole 100 and the first mounting portion 101 .

[0048] In this embodiment, the process hole 103 is used for positioning, fixing and operating convenience during the manufacturing and assembly process. For example, the head arm 1 can be formed by stamping or cutting. The edge of the head arm 1 formed by this process has burrs and the surface is not smooth, and subsequent grinding is required. The process hole 103 can be used to fix the head arm 1 during the grinding process to avoid the movement of the head arm 1 and prevent the head arm 1 from being damaged. For another example, during the assembly process of the head drive arm assembly, the process hole 103 allows the use of specific clamps or positioning pins to ensure the precise alignment of the head suspension 10 during the assembly process. This is necessary to ensure the correct installation and positioning of the head, reduce human errors in the assembly process, and improve the consistency and reliability of the assembly.

[0049] In the above embodiment, the setting of the process hole 103 can further reduce the weight of the head arm 1. The lighter head arm 1 can respond to the driving force of the voice coil motor more quickly, thereby increasing the speed at which the head moves to the target track and reducing the seek time.

[0050] See also Figures 2 to 4 In one embodiment, the surface of the process hole 103 close to one end of the pivot hole 100 and one end close to one end of the first mounting portion 101 is an arc surface, and the inner diameter of the arc surface close to one end of the pivot hole 100 is larger than the inner diameter of the arc surface close to one end of the first mounting portion 101.

[0051] In this embodiment, the two ends of the process hole 103 are arc surfaces, and the inner diameters of the two arc surfaces are different, which is more conducive to the heat dissipation of the magnetic head arm 1. It should be noted that the voice coil motor will generate heat during operation, especially when it is frequently started and stopped. Due to the process of converting electrical energy into magnetic energy and mechanical energy, part of the energy is transferred to the magnetic head arm 1 in the form of heat energy. At the same time, when the magnetic head writes data, it is necessary to change the magnetization state of the disk surface. This process involves the current passing through the magnetic head to generate a magnetic field, which will also generate a certain amount of heat. This part of the heat will also be transferred to the magnetic head arm 1, and the heat dissipation method of the magnetic head arm 1 is that the surface contacts the air and transfers the heat to the air to achieve the purpose of heat dissipation. The two ends of the process hole 103 are set as arc surfaces, and the inner diameters of the two arc surfaces are different, which leads to the surface connecting the two arc surfaces being an inclined surface. Compared with the rectangular surface, a larger area can be formed. This part of the area can be used for heat dissipation inside the magnetic head suspension 10, thereby improving the heat dissipation efficiency.

[0052] In one embodiment, the head arm 1 is made of aluminum.

[0053] In this embodiment, aluminum has a low density, and the use of aluminum can reduce the weight of the magnetic head arm 1, thereby reducing its inertia when moving, improving the response speed and positioning accuracy. At the same time, aluminum is a good thermal conductor, which can effectively conduct away the heat generated by the magnetic head arm 1, especially the heat generated during the reading and writing operations of the magnetic head arm 1 and the operation of the voice coil motor, thereby reducing the risk of overheating.

[0054] The limiting process of the limiting protrusion 111, the first limiting groove 112 and the second limiting groove 113 of the magnetic head arm 1 is as follows:

[0055] The limiting protrusion 111 is limited: the energized voice coil is subjected to the Ampere force in the magnetic field, and the Ampere force drives the head arm 1 to swing around the rotation axis in the direction where the limiting protrusion 111 is set. When the driving arm 11 rotates to the maximum position, the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 in the limiting protrusion 111 can adapt to the surface of the limiting column. After the limiting protrusion 111 contacts the adapted surface of the limiting column, the limiting and parking of the head arm are completed.

[0056] The first limiting groove 112 and the second limiting groove 113 cooperate for limiting: the energized voice coil is subjected to the Ampere force in the magnetic field, and the Ampere force drives the head arm 1 to swing around the direction of the limiting protrusion 111 set on the rotation axis. When the driving arm 11 rotates to the maximum position, the first limiting groove 112 and the second limiting groove 113 simultaneously contact the surfaces matched with the corresponding limiting columns to achieve the limiting of the driving arm 11.

[0057] In summary, compared with the prior art, the technical solution of the present application is to set a limiting protrusion 111 on the driving arm 11, and the first arc segment 1110, the second arc segment 1111 and the limiting segment 1112 on the limiting protrusion 111 are connected, and the limiting column is provided with a matching contact surface. When an abnormal situation such as sudden power failure, mechanical shock or control failure occurs, causing the magnetic head arm to collide with the limiting column, the position where the limiting protrusion 111 collides with the limiting column is a surface contact, which is more stable during contact. The surface contact can better disperse the load and reduce the mechanical damage caused by local overload. At the same time, the area of ​​the first arc segment 1110 and the second arc segment 1111 of the present application is larger than the area of ​​the inclined surface or the single curved surface under the same conditions. When used to contact with the corresponding matching limiting column, the contact surface is larger, which is more conducive to dispersing the load and reducing the mechanical damage caused by local overload.

[0058] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A magnetic head arm for a hard disk drive, characterized in that: include: A head suspension and a driving arm, wherein the head suspension and the driving arm are integrally connected; A pivot hole is provided at the connection between the head suspension and the driving arm, and the pivot hole is used to install the rotating shaft; an accommodating groove is provided at one end of the driving arm away from the pivot hole, and the accommodating groove is used to install the voice coil; A limiting protrusion is arranged on one side of the driving arm, and the limiting protrusion comprises a first arc segment, a second arc segment and a limiting segment with a concave surface facing the accommodating groove, and the first arc segment, the second arc segment and the limiting segment are connected in sequence.

2. The magnetic head arm of the hard disk drive according to claim 1, characterized in that: A first mounting portion is disposed at one end of the head suspension away from the driving arm, and the first mounting portion is used for mounting a magnetic head or a flexible arm.

3. The magnetic head arm of the hard disk drive according to claim 2, characterized in that: The first mounting portion is formed by inward depression of one or both sides of the end of the magnetic head arm.

4. The magnetic head arm of the hard disk drive according to claim 1, characterized in that: A second mounting portion is disposed on a side of the head cantilever away from the limiting protrusion, and the second mounting portion is used for mounting a flexible circuit board.

5. The magnetic head arm of the hard disk drive according to claim 4, characterized in that: The driving arm is provided with a first limiting groove at one end away from a side surface of the limiting protrusion and close to the second mounting portion.

6. The magnetic head arm of a hard disk drive according to claim 4, characterized in that: The driving arm is provided with a second limiting groove on a side surface away from the limiting protrusion and on an end away from the second mounting portion.

7. The magnetic head arm of a hard disk drive according to claim 1, characterized in that: A convex rib is arranged inside the pivot hole.

8. The magnetic head arm of a hard disk drive according to claim 2, characterized in that: The head suspension is provided with a process hole, and the process hole is arranged between the pivot hole and the first mounting portion.

9. The magnetic head arm of the hard disk drive according to claim 8, characterized in that: The surfaces of the process hole close to one end of the pivot hole and one end of the first mounting portion are arc surfaces, and the inner diameter of the arc surface close to one end of the pivot hole is larger than the inner diameter of the arc surface close to one end of the first mounting portion.

10. The magnetic head arm of a hard disk drive according to any one of claims 1 to 9, characterized in that: The material of the magnetic head arm is aluminum.

Images