JP2006026050A - Headrest - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel headrest having a strong securing force even though positional adjustment to a chair, or the like, and positional securing after that can be readily done. <P>SOLUTION: This headrest 1 according to the present invention has a support body 2 directly assuming the support of a head, and a joint portion 3 for arranging the support body 2 in a portion CH to be secured, a ball joint mechanism by a ball portion 6 having a joint ball 13 and a socket portion 7 receiving the ball is employed in the joint portion 3, the support body 2 can be changed in an angle in a suitable range relatively to the portion CH to be secured and can be set in a proper position. The proper position can be kept by pinching the joint ball 13 from inside of the socket portion 7 realizing articulation-like rotational sliding to block the movement of the ball in securing the headrest 1 to the proper position after the adjustment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a headrest that can be attached to a wheelchair or the like, and particularly relates to a novel headrest that can be easily positioned and can be easily and securely fixed to an appropriate position once determined. .

  For example, a chair such as a wheelchair may be provided with a headrest to support a seated person's head from behind and stabilize it at a comfortable and appropriate position. And in this kind of headrest, there are things fixed to the chair, but considering that the seated person changes the sitting posture, the angle of the backrest, etc. Some can be adjusted freely. In this case, the headrest is often attached to the chair by applying several sliding members, rotating members, etc., and the position and angle can be changed as appropriate. Etc. have become common (see, for example, Patent Document 1).

However, in such a method, there are many problems that the individual movable members involved in position adjustment have a single function such as only vertical sliding or only horizontal sliding, and the number of mounting members increases. It was. In addition, due to such design specifications, individual movable members are often provided with dedicated clamps, and as a result, the number of clamps to be tightened is increased when fixing the adjusted headrest in the proper position. The work (operation) required a lot of labor and time.
Also, in the technique that requires a lot of clamps, for example, even if the first clamp is tightened to fix the vertical position of the headrest, when the other clamp that fixes the left and right positions is tightened, the already determined vertical position is subtly In many cases, the headrest is displaced and it is actually very difficult to fit the headrest exactly at the adjusted proper position.

  For this reason, the present applicant has attempted a connection method using a ball joint mechanism in order to more easily adjust and fix the position of the headrest. In other words, this method forms a joint ball on the back side of the headrest and forms a socket part for wrapping the joint ball on the backrest part of the chair, etc. The joint shape of the joint ball accommodated in the socket part The headrest is angularly displaced within an appropriate range by the above-described rotational sliding. Further, in order to fix the headrest at an appropriate position after adjustment, a set screw that is often used as a means for mechanically fixing the movable member is often used.

  However, such a fixing method using a set screw has the following problems. In other words, the set screw is basically in contact with the joint ball in a point contact state to prevent the movement of the ball, so the fixing force per one is relatively weak, and therefore it is generally distributed at multiple locations. It was the target. However, providing a plurality of set screws necessitates screwing or loosening at several points during fixing or adjustment, and the work is complicated.

  In the case of a set screw, a tool is inevitably necessary (for example, a slotted screw requires a negative screwdriver, and a hexagon socket head screw uses a hex wrench (hex It takes a lot of trouble to install a tool permanently. In particular, when the headrest is to be attached to a wheelchair, this tool moves, so that the permanent installation of the tool is not necessarily a suitable form. In addition, if the wheelchair user is an elderly person who needs nursing care or a person whose physical function makes it difficult to support the head according to his / her will, the appropriate position of the headrest is frequently determined according to the content of nursing care or assistance. The fixing operation at a plurality of locations, which requires tools, has forced a caregiver (helper) to take a great burden.

  For this reason, for example, a ball joint mechanism similar to a collet chuck has been considered as a technique that can be fixed by one touch operation without using a tool as much as possible. For example, as shown in FIG. 7, a slit SL is formed in the socket portion 7 'in advance so that the size of the portion for receiving the joint ball 13' can be appropriately changed. A screw N is provided on the outer periphery of 7 ', and when the headrest 1' is fixed at an appropriate position, the screw N is tightened to reduce the size of the socket portion 7 'and to move the joint ball 13'. It is something to stop.

However, in this case, since the screw N is provided on the outer periphery of the socket part 7 ', the socket part 7' is enlarged, and there is a problem that the joint part 3 'is not compact.
Further, in such a method, the chucking force (fixing force) for holding the joint ball 13 ′ by the socket portion 7 ′ is not always sufficient, and the movement of the ball cannot be surely stopped. For example, as shown in the enlarged view of FIG. 7, even if the inner portion (ball receiving portion) of the socket portion 7 ′ is designed to be the same size as the joint ball 13 ′, in a natural state where no force is applied, Since the socket portion 7 'expands due to the slit SL, even if the receiving portion is narrowed by tightening the screw N, a gap is easily formed between the joint ball ball 13' and the socket portion 7 '. It is considered that a sufficient chucking force cannot be obtained.
For this reason, there has been a demand for a headrest having a support mechanism that can provide a reliable fixing force while allowing easy position fixing.
JP2001-293036

  The present invention has been made in view of such a background, and it is possible to easily adjust the position relative to a chair or the like, or to perform subsequent position fixing easily, but to obtain a strong fixing force. This is an attempt to develop a headrest.

  That is, the headrest according to claim 1 is a member that is mounted on a mounted portion such as a chair and supports the head of the seated person, and this member includes a support body that directly supports the head, and the support body. And a joint portion for providing a joint ball to the mounted portion, and a ball joint mechanism including a ball portion having a joint ball and a socket portion for receiving the joint ball is applied to the joint portion. While the support body can be angularly displaced within an appropriate range with respect to the attached portion and set to an appropriate position, an articulated rotational slip is realized in maintaining and fixing the position of the headrest after adjustment. It is characterized by holding the joint ball from the inside of the socket part to prevent the movement of the ball and maintaining the proper position It is.

  According to a second aspect of the present invention, in addition to the requirement of the first aspect, the socket portion is formed with a ball-shaped contact surface that sandwiches the joint ball from two opposite directions, and maintains the headrest in an appropriate position. When fixed, the joint ball is sandwiched by a ball-shaped contact surface to prevent the ball from sliding.

  Furthermore, in addition to the requirements of claim 1 or 2, the socket portion comprises a pipe-shaped socket body and a pressing piece slidably inserted therein. The joint ball is received between the socket main body and the pressing piece, and the socket main body and the pressing piece are formed with a ball-shaped contact surface at a portion for receiving the joint ball. Yes, when adjusting the position of the headrest, the joint ball is rotatably supported by the contact surfaces of both the socket body and the pressing piece, and when the headrest is maintained and fixed at an appropriate position, The joint ball is firmly sandwiched between the contact surfaces to prevent the joint ball from rotating.

  According to a fourth aspect of the present invention, in addition to the requirement of the third aspect, in order to prevent the rotation of the joint ball, the pressure piece is pushed into the socket body by screwing a bolt to firmly hold the joint ball. This is what makes it a feature.

  According to a fifth aspect of the present invention, in addition to the requirements of the first, second, third, or fourth aspect, the attached portion is a backrest portion of a wheelchair.

  In addition to the requirements of claim 1, 2, 3, 4 or 5, the headrest of claim 6 is set so that the clamping direction of the joint ball is substantially along the head support direction by the headrest. It is characterized by being done.

  The above-described problems can be solved by using the configuration of the invention described in each of the claims. That is, according to the first aspect of the present invention, the joint ball is clamped from the inside of the socket portion so as not to move, so that the ball is regulated. Can be realized.

  According to the second aspect of the present invention, the joint ball is held so as to be sandwiched by the spherical contact surfaces from two opposing directions, so that the movable support state allowing the rotation of the ball and the rotation of the ball are prevented. The fixed support state can be easily switched depending on the holding force, and the ball can be fixed securely.

  Furthermore, according to the third aspect of the present invention, a headrest having a ball joint mechanism that can be fixed and easily fixed at an appropriate position and that is compactly assembled is made concrete.

  According to the invention described in claim 4, since the pressing piece is pushed in by screwing in the bolt at the time of fixing, a high clamping force is obtained, and the fixing of the joint ball, that is, the fixing of the headrest is further ensured.

  According to the fifth aspect of the present invention, since the headrest is attached to the wheelchair, the operation of adjusting the head of the wheelchair user (sitting person) to an appropriate position can be performed easily and reliably. In particular, wheelchairs are often used by elderly people, people with physical disabilities, or injured persons (patients), and the head support position must be changed frequently according to work (behavior) such as meals and normal movements. In some cases, the support position can be changed very easily. For this reason, the burden on the caregiver (helper) can be reduced.

  According to the sixth aspect of the present invention, since the holding direction of the joint ball and the head support direction of the headrest are set so as to be substantially along, the maintenance and fixing of the joint ball can be performed more reliably.

  The best mode of the present invention is as described in the following examples.

  As shown in FIG. 1 as an example, the headrest 1 of the present invention is attached, for example, above the back portion BR of the chair CH and supports the back of the seated person M. The attachment to the chair CH is spherical. Adopts a ball joint mechanism that realizes the rotational slip of. That is, the headrest 1 of the present invention has a support body 2 that substantially supports the head and the support body 2 attached to a mounted portion CH (same as CH for the chair) such as a chair CH (backrest portion BR). And a joint part 3 for carrying out. And the ball | bowl part 6 which has the joint ball 13 is formed in the back side (side facing a head support) of this support main body 2, and the socket part 7 which receives this joint ball | bowl 13 in the chair CH etc. is formed. The ball portion 6 is accommodated in the socket portion 7 to realize an articulated rotational slide (so-called ball universal joint), whereby the headrest 1 is freely angularly displaced within an appropriate range.

Further, the headrest 1 of the present invention includes a lock portion 4 that prevents rotational slippage of the joint ball 13 and maintains and fixes the appropriate position in order to fix (maintain) the appropriately adjusted appropriate position easily and reliably by a one-touch operation. Is.
Note that the chair CH is not limited to the wheelchair shown in FIG. 1, and an office chair, an easy chair (rest chair), a seat seat for a passenger car, a treatment seat used for dental treatment, and the like are applicable. Incidentally, the mounted portion CH to which the headrest 1 is mounted is generally such various chairs CH, but is not necessarily limited to the chair CH, which will be described later in [Other Examples]. .
Hereinafter, the joint part 3 and the lock part 4 will be described.

First, the joint part 3 will be described. The joint portion 3 is a portion that realizes a joint-like or spherical rotational slip and enables the position adjustment (angular displacement) of the headrest 1, and includes the ball portion 6 and the socket portion 7 as described above. .
As shown in FIGS. 1 and 2 as an example, the ball portion 6 includes a stay 12 attached to the back side of the support body 2 and a joint ball 13 provided at the tip of the stay 12. The ball 13 is received in the socket portion 7 to realize a joint-like rotational slip.
On the other hand, the socket portion 7 includes a socket main body 17 formed in a pipe shape and a pressing piece 19 that is slidably fitted therein, and accommodates the joint ball 13 therebetween.

The socket body 17 is narrowed on the stay 12 side so that the joint ball 13 received between the pressing piece 19 and the socket body 17 does not come out, and a contact surface 18 for receiving the outer peripheral surface of the ball is formed here.
In addition, the pressing piece 19 is formed in a U-shaped cross section with a recessed central portion, and a contact surface 20 that receives the outer peripheral surface of the ball is formed at a portion that contacts the ball. In addition, the dent of the center part is for receiving the joint ball | bowl 13 equally by the circumferential contact surface 20, and avoiding a contact with the joint ball | bowl 13. FIG. For this reason, the joint piece 13 is also partially cut away on the side of the pressing piece 19 within a range that does not hinder angular displacement (this is referred to as a contact avoiding portion 14).

  Each of the contact surfaces 18 and 20 is formed in a spherical band shape having an appropriate width and an R-surface shape substantially equal to that of the joint ball 13, and by adjusting the force for pinching the ball, Rotational sliding (movable support state) and maintenance fixation (fixed support state) for preventing the movement of the ball are appropriately achieved. That is, when the joint ball 13 is supported by the two contact surfaces 18 and 20 in the rotation-permitted state from the two opposing directions, the position of the headrest 1 can be adjusted by the rotational sliding of the ball. , 20, when the ball is firmly sandwiched to prevent the movement (rotational slip) of the ball, the headrest 1 can be maintained and fixed (locked).

  In other words, as shown in the schematic diagram of FIG. 3, for example, the joint ball 13 is always supported from both sides by two plate-like members (corresponding to the spherical contact surfaces 18 and 20). Therefore, as shown in FIG. 3B, when the ball is firmly sandwiched between the two plate-like members, the rotation of the ball is prevented, and the headrest 1 can be fixed at an appropriate position. As shown in FIG. 3A, when the strong pinching of the ball is released, the position of the headrest 1 can be adjusted by the rotational sliding of the ball.

  Next, the lock unit 4 will be described. The lock portion 4 prevents rotation of the joint ball 13 and fixes the adjusted position of the headrest 1. In this embodiment, the contact piece 18 of the socket body 17 is pressed by pressing the pressing piece 19 against the ball side. And the ball is firmly sandwiched between the contact surface 20 of the pressing piece 19 and the rotation of the ball is prevented. For this reason, as shown in FIGS. 1 and 2, for example, the lock portion 4 includes a pipe-like lock portion main body 31 attached (screwed here) to the socket main body 17, and a nut 32 fixed therein. And a bolt 33 fitted into the nut 32. That is, in this embodiment, the pressing piece 19 is pushed in by screwing the bolt 33, and thereby, the ball is strongly sandwiched between the socket body 17 and the pressing piece 19. For this reason, it is desirable that a knurling or the like is appropriately formed on the rear end knob (head) of the bolt 33 so that it can be easily screwed by hand. In the embodiment shown in FIGS. 1 and 2, a hexagonal hole is formed in the rear end knob of the bolt 33 so that it can be tightened with a hexagon wrench.

As described above, in this embodiment, the joint ball 13 is sandwiched by the ball-shaped contact surfaces 18 and 20 to prevent the rotation of the joint ball 13, thereby obtaining a sufficient fixing force. As shown in FIG. 1, it is possible to further strengthen the fixation (adhesion) of the ball by using the set screw SC together.
In this embodiment, when adjusting the position of the headrest 1, the bolt 33 described above is loosened so that the ball can slide while being in contact with the contact surfaces 18 and 20, and the ball is rotated (sliding contact). However, at this time, even if the bolt 33 is greatly loosened, the lock portion main body 31 can regulate the movable end (sliding end) of the pressing piece 19. It will never change.
The embodiment shown in FIGS. 1 and 2 adopts a form in which the lock portion main body 31 is fitted in the socket main body 17 mainly for the purpose of making the joint portion compact.
[Other Examples]

  The present invention is based on the above-described embodiment as a basic technical idea, but the following modifications can be considered. That is, in the embodiment described above, the joint ball 13 is sandwiched and supported by the ball-shaped contact surfaces 18 and 20 from two opposing directions, and this allows the ball to rotate by the strength with which the ball is sandwiched. This is a very rational support method in that it realizes a movable support state that performs the above and a fixed support state that prevents the rotation of the ball. However, the support form of the joint ball 13 is not limited to the sandwiching between the two ball-shaped contact surfaces 18 and 20, but the pressing piece 19 can be omitted, for example, as shown in FIG. In other words, the joint ball 13 is sandwiched (supported) by the contact surface 18 and the tip of the bolt 33. In this case, as shown in FIG. 4 above, for example, if the tip of the bolt 33 is formed in an R-concave shape that is approximately the same as the ball diameter, the tip surface of the bolt 33 is flatter than the case. It is considered that the support of the ball can be stabilized.

In the basic embodiment described above, the bolt 33 is screwed on the basis of an operation using a knurling formed on the rear end knob portion, and the screwing using a hexagon wrench is appropriately performed. In particular, when the attached portion CH is a wheelchair, it is conceivable that a hexagon wrench is a heavy burden for wheelchair users. For this reason, for example, as shown in FIG. 5, it is possible to pin the clamp lever 36 to the bolt 33 in advance and make the lever foldable (so-called pin lever). When such a pin lever type clamp lever 36 is added to the bolt 33, when the bolt is tightened, the clamp lever 36 is rotated 90 degrees with respect to the axis of the bolt 33, and the bolt 33 is tightened (rotated). ), A large torque can be obtained, and the fixing force can be further strengthened.
Of course, in order to obtain a sufficient fixing force without using a tool, not only the clamp lever 36 but also a butterfly bolt can be applied.

  Furthermore, in the basic embodiment described above, the direction in which the joint ball 13 is sandwiched is set so as to be substantially along the direction (reference axis) for supporting the head of the seated person M. In this case, It cannot be denied that the pipe-shaped lock portion main body 31 and the like protrude beyond the headrest 1. However, for example, when the headrest 1 is attached to a seat or the like of a passenger car, since a person sits on the rear side, such a rear overhang is not necessarily preferable. Therefore, in such a case, for example, as shown in FIG. 6, the clamping direction of the joint ball 13 can be set substantially perpendicular to the support direction (reference axis) of the head. That is, when adopting such a support form, the reference position of the headrest 1 is substantially horizontal, and the clamping direction of the joint ball 13 is substantially vertical.

In the basic embodiment described above, the headrest 1 is attached to the chair CH because it is generally attached to the chair CH. However, the headrest 1 is not necessarily attached to the chair CH. There is no. For example, the headrest 1 is rarely provided in advance in a wheelchair, and many are provided later (so-called option). In recent years, there have been an increasing number of cases in which a seated person M is carried on a motor vehicle together with such a wheelchair. In such a case, the car side, for example, a vehicle body, a stand for raising and lowering a wheelchair, or a wheelchair It is also possible to attach the headrest 1 of the present invention from a stand or the like that fixes the inside of the vehicle with an intermediate member interposed as appropriate.
Further, even if the patient or the like is normally in a bed that is used in a flat state, for example, when the patient is raised and used as a chair, the headrest 1 of the present invention is used when the patient sits on the bed. It is possible to attach. The “attached part” described in claim 1 of the present specification is a reclining in which various chairs CH, a fixed base on which a wheelchair is placed, a lifting base, or a chair-like use can be considered. It includes a bed of a type in a broad sense.

It is explanatory drawing (a) which shows the state which attached the headrest of this invention to the wheelchair, and the perspective view (b) which expands and shows the internal structure of the joint part and lock part of this headrest. It is a half sectional view showing the headrest of the present invention. It is a perspective view which shows typically the movable support state which permits rotation of a joint ball by the spherical contact surface which opposes, and the fixed support state which prevents rotation of a joint ball. It is explanatory drawing which shows the other Example which pinched and supported the joint ball by pinching | interposing the ball | bowl-shaped contact surface and a bolt front-end | tip. It is a perspective view which shows the other Example which pinned the clamp lever for operation to the rear end of the volt | bolt which pushes in a press piece. It is explanatory drawing which shows the other Example which varied the clamping direction of the joint ball, and the head support direction of the headrest. It is explanatory drawing which shows the problem of the ball joint mechanism similar to the collet chuck type.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Headrest 2 Support main body 3 Joint part 4 Lock part 6 Ball part 7 Socket part 12 Stay 13 Joint ball 14 Contact avoidance part 17 Socket main body 18 Contact surface 19 Pressing piece 20 Contact surface 31 Lock part main body 31
32 Nut 33 Bolt 36 Clamp lever BR Backrest CH Mounted part (chair)
M Seated person N Screw SC Set screw SL Slot

Claims (6)

A member that is attached to a mounted part such as a chair and supports the head of the seated person,
In this member, a support main body that directly supports the head and a joint portion for providing the support main body on the attached portion are formed.
In addition, a ball joint mechanism including a ball part having a joint ball and a socket part for receiving the joint ball is applied to the joint part.
While the support body can be angularly displaced with respect to the mounted part within an appropriate range and set to an appropriate position, while maintaining and fixing the position of the headrest after adjustment, the socket part that realizes joint-like rotational sliding is used. A headrest characterized by holding a joint ball from the inside to prevent movement of the ball and maintaining an appropriate position. The socket portion is formed with a ball-shaped contact surface that sandwiches the joint ball from two opposing directions,
2. The headrest according to claim 1, wherein when the headrest is maintained and fixed at an appropriate position, the joint ball is held by a ball-shaped contact surface to prevent the ball from sliding. The socket part comprises a pipe-shaped socket body and a pressing piece slidably inserted therein, and the joint ball is received between the socket body and the pressing piece,
In addition, the socket body and the pressing piece are formed with a ball-shaped contact surface at a portion that receives the joint ball,
When adjusting the position of the headrest, the joint ball is rotatably supported by the contact surfaces of both the socket body and the pressing piece,
3. The headrest according to claim 1, wherein when the headrest is maintained and fixed at an appropriate position, the joint ball is firmly sandwiched between both contact surfaces to prevent rotation of the joint ball.   4. The headrest according to claim 3, wherein when the rotation of the joint ball is prevented, the pressing piece is pushed into the socket body by screwing a bolt so as to firmly clamp the joint ball.   The headrest according to claim 1, wherein the attached portion is a backrest portion of a wheelchair.   6. The headrest according to claim 1, wherein a clamping direction of the joint ball is set so as to substantially follow a head support direction by the headrest.

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