Bed With Dually Positionable Head Support

1. Industrial Field of Application

This invention relates to a bed capable of raising the upper part of a person's body.

2. Description of the Prior Art

In previous beds capable of raising the upper part of a person's body, the back supporting frame, which forms a plane when raised, forced the user to remove his/her pillow and articles put on the back supporting frame in order to prevent them from falling every time the back supporting frame was raised.

This invention prevents a pillow and articles put on the front area of the bed from falling when the front area is raised.

In this invention the head supporting frame 21c is connected to the front of the back supporting frame 21b, which can be raised and pivoted at any angle, so that the frame 21c can be bent freely at a joint. A posture change-over means 30 is provided to select between two pivoting states of the head supporting frame 21c when the back supporting frame 21b is raised and pivoted. The two states are: a first state in which the head supporting frame 21c is pivoted in the same plane as the back supporting frame 21b and a second state in which the head supporting frame 21c is kept in the horizontal posture while pivoting.

In the bed capable of raising the upper part of a person's body according to this invention, the posture change-over means 30 has a rod 28 whose fixed end is connected to the protruding arm 27 under the head supporting frame 21c and other end can be fitted to either of a bracket 22a of the bed frame or a bracket 29 of the back supporting frame 21b.

If the rod is connected to the bracket under the back supporting frame before the back supporting frame is raised, the head supporting frame is held in a condition that the head supporting frame and the back supporting frame form a plane. The plane consisting of the frames, extends upwardly and pivots about a pivot point in the same manner as the previous beds capable of raising the upper part of a person's body. If the rod is connected to the bracket of the bed frame, a parallel link is made, and the head supporting frame is always kept horizontal, thereby preventing a pillow and other articles on the head supporting frame from falling.

FIG. 1 is a side view of the whole bed.

FIG. 2 is a plan view of the whole bed.

FIG. 3 is a side view of a pivoting frame.

FIG. 4 is a side view of the pivoting frame.

FIG. 5 is a plan view of the pivoting frame.

FIG. 6 is a side view of a principal part of a pivoting frame actuating mechanism.

FIG. 7 is a plan view of the principal part.

FIG. 8 shows how a posture change-over means operates.

FIG. 9 shows how the posture change-over means operates.

FIG. 10 is a side view of a handrail.

FIG. 11 is a side view of a pivoting mechanism of the handrail.

FIG. 12 is a front view of a principal part showing how the handrail pivots.

FIG. 13 is a plan view showing the pivoting process of the pivoting frame actuating mechanism.

FIG. 14 is a plan view showing the pivoting process of the pivoting frame actuating mechanism.

FIG. 15 is a plan view showing the pivoting process of the pivoting frame actuating mechanism.

FIG. 16 is a plan view showing the pivoting process of the pivoting frame actuating mechanism.

FIG. 17 is a side view of a principal part showing a bending process of a front bed section.

FIG. 18 is a side view of the principal part showing a bending process of the front bed section.

FIG. 19 is a side view of the principal part showing a bending process of the front bed section.

FIG. 20 is a side view of the principal part showing a bending process of the front bed section.

FIG. 21 is a side view of the principal part showing a bending process of the front bed section.

FIG. 22 is a side view of the whole bed in the raised state.

FIG. 23 is a side view of the bed when a person on the bed is in the posture to take a meal or when the bed is in the pivoting start position.

FIG. 24 is a side view of the bed when the pivoting frame has completed pivoting and a person on the bed is going to go down on the floor.

An embodiment of this invention is explained below according to the figures.

In FIG. 1, a fixed frame 1 of the bed is supported by front feet 2 and rear feet 3. When viewed from the side, its center part in the longitudinal direction descends, and when viewed from above, right and left side frames 1a and 1b are connected by joining frames 1c (see FIG. 13). Parts 4 and 5 are a front board and a rear board, respectively.

A pivoting frame 6 (see FIGS. 3-5) of the bed is fixed to a pivoting plate 8 which is held by upper and lower bearings between a lower fixed ring 7a fixed to the joining frame 1c located in the descending center part of the fixed frame 1. An upper fixed ring 7b is integrally fixed to the lower fixed ring 7a so that the pivoting plate 8 can pivot freely. The pivoting frame 6 comprises side frames 6a and 6b provided on the left and right sides of the bed in the longitudinal direction, two tie frames 6c for connecting to the pivoting plate 8, and a mounting frame 6d to which the tie frames 6c are connected.

The above-mentioned pivoting frame 6 has the pivoting mechanism as described below. At first, fixed cams 9a and 9b are fixedly secured on the right and left areas on the upper face of the fixed ring 7b in the protruded state, and the fixed cams 9a and 9b have cam grooves A and B, respectively, to displace the mating part inward from the back toward the front.

On the other hand, the pivoting frame 6 is provided with an integrally fixed transmission mounting frame 16 having a rectangular shape when viewed from above (see FIGS. 6-7). A motor 10 is mounted in this frame 16 with the drive output shaft 10a set in the longitudinal direction, and a screw shaft 12 is connected to the shaft 10a in the longitudinal direction through a friction transmission joint 11 serving also as a shock absorber. The screw shaft 12 is received on bearings of the transmission mounting frame 16 so that the shaft can freely pivot. A screw cylinder 13 is screwed onto the screw shaft 12 and provided with shafts 14 and 15 on the right and left sides to prevent the shaft 13 from rotating. The shafts 14 and 15 are provided with rollers 17 which roll on the right and left frames 16a and 16b of the frame 16, keeping contact with them.

A lateral frame 18 has holes 18a and 18b on the right and left ends, to one of which cam pin 19 is inserted. When the pin 19 is inserted into the hole 18a or 18b on the lateral frame 18 and the motor is started to move the screw cylinder 13 forward, the lower end of the pin 19 is fitted into the cam groove A (cam 9a) or B (cam 9b) and pivots the pivoting frame 6 rightward or leftward through the transmission mounting frame 16 in cooperation with the motor 10 (see FIGS. 13-16). Rotating the motor 10 reversely to move the screw cylinder 13 backward draws out the pin 19 backward from the cam groove A or B, and the cam action obtained in this time causes the pivoting frame 6 to pivot in the reverse direction to the above-mentioned direction to return to its origin. The pivoting angle of the pivoting frame 6 varies depending on the displacement angle and length of the cam grooves A and B. In this invention, the cam grooves are designed so that the friction transmission joint 11 functions to stop the pivoting frame 6 when it pivots approximately 90.degree..

The pivoting frame 6 is connected with the front bed supporting frame 21 supporting the front bed section 20a for receiving the upper part of a person's body above the femur as follows; the pivoting frame 6 is provided with a reverse U-shaped protruding frame 22 (see FIGS. 8-9) which has brackets 24 and 25 to fit the waist supporting frame 21a and the back supporting frame 21b, respectively. The base sides of the supporting frames 21a and 21b are secured with pins 23 so that they can pivot freely, and their moving ends are properly supported by the pivoting frame 6 so that the frames are kept substantially horizontally. Also, the head supporting frame 21c is fitted to the front of the back supporting frame 21b so that the frame 21c can pivot freely with the aid of a pin 26. The front of a protruding arm 27, under the head supporting frame 21c, is connected to the bracket 22a on the protruding frame 22 through a rod 28. When the back supporting frame 21b is pivoted upward, only the head supporting frame 21c is kept in the horizontal posture. When the base of the rod 28 is connected to the bracket 29, fixed on the back supporting frame 21b, the head supporting frame 21c is not kept horizontal when the back supporting frame 21 is pivoted; it moves together with the back supporting frame 21b. Thus, a posture change over means 30, for changing the posture of the head supporting 21c by changing the mounting position of the rod 28, functions between the back supporting frame 21b and the head supporting frame 21c.

Cylinders 32 are provided on the four corners of the pivoting frame 6 to attach handrails 31. The handrail 31 (see FIGS. 10-12) comprises a gate-shaped fixed handrail 31a which is inserted into the cylinders 32 from above and a pivoting handrail 31b which is inserted into the handrail 31a in the longitudinal direction through a boss 31c integrally secured on the rear upper part of the fixed handrail 31a and held with a screw 33 and a drawing-out preventive groove 34a cut on an insertion shaft 34. The pivoting handrail 31b is made of a pipe which is formed in a substantially elliptical loop and designed so that it can be set in two positions, i.e. in the hanging-down position and in the slanting position (at which it is held inward and slightly slanting), by means of pivoting stoppers 31d and 34d provided on the boss 31c and the pivoting handrail 31b at the end face of the insertion shaft 34, respectively.

A cylinder 34c is a safety cover for the stopper section. The front bed section 20a has an ordinary bendable bed mat, which is placed on the upper surface of the front bed supporting frame 21 set on the pivoting frame 6 as described above. The rear edge of the front bed section 20a is formed in a circular arc which has radius extending from a center of the pivoting frame 6.

The rear bed section 20b is placed on the upper surface on the rear side of the fixed frame 1. The front edge is formed in a circular arc traced with a radius extending from a center of the pivoting frame 6. The projections C and D on the right and left sides of the bed section 20b having an arched edge when viewed from above are inclined gradually lower than the other surfaces toward the ends.

Below is explained the pivoting mechanism of the waist supporting frame 21a and the back supporting frame 21b mounted on the pivoting frame 6 through the protruding frame 22 so that they can pivot. Under the supporting frames 21a and 21b, cam rollers 37 and 38 are fitted through brackets 35 and 36 (see FIGS. 17-21), respectively, so that they can roll through lateral shafts. Also, a cam 39, with which the cam roller 37 is put into contact, is fixed on the right side of the lateral frame 18 integrally secured to the screw cylinder 13. A cam 40 with which the cam roller 38 is put into contact, is fixed on the left side. When the screw cylinder 13 is moved forward by rotating the screw shaft 12 by the motor 10, the cam roller 38 is pushed by the vertical front face of the cam 40 to cause the back supporting frame 21b to pivot gradually backward, and, almost simultaneously, the cam roller 37 is gradually moved up by the cam 39 to cause the rear side of the waist supporting frame 21a to pivot somewhat upward. Then, a few seconds before the condition shown in FIG. 19 occurs, the cam pin 19 inserted into the hole 18a or 18b at the end of the lateral frame 18, is fitted into the cam groove A or B of the fixed cam 9a or 9b on the side where the pin is located. After this, the screw cylinder 13 moves forward, and when the pin 19 reaches the displacing zone of the cam groove, the pivoting frame 6 starts pivoting to the left or right. When the pivoting frame pivots approximately 45.degree., the back supporting frame 21b is turned down slightly, and at the same time the waist supporting frame 21a gradually becomes sharp in inclination while the pivoting frame 6 further pivots. Then, when the pivoting frame 6 reaches the pivoting limit of approximately 90.degree., the back supporting frame 21b is set in the vertical position, and the waist supporting frame 21a returns to the horizontal position. The positional relation between cams and pins or cam rollers and the shape of cams are designed so that the above-mentioned movements can be obtained.

A switch box 41 (see FIG. 7) to operate the motor 10 is provided with a cord so that a handicapped person, or aged person on the bed or a person who looks after him/her can operate the motor from any position and change the switch to rotate the motor 10 in the regular or reverse direction, i.e. to change the rotation direction of the screw shaft 12 to move the screw cylinder 13 forward or backward.

A slide member 42 (see FIGS. 2 and 22) made of leather or synthetic rubber is applied to the arched face of the front bed section 20a (convex edge) or the rear bed section 20b (concave edge) or to both the faces to pivot the section 20a smoothly.

The mechanism of the above-mentioned embodiment is described below.

A handicapped person or an aged person is laid on the bed with the upper half of the body above the waist on the front bed section 20a and with the legs on the rear bed section 20b. When he/she wants to raise his/her upper part of body from the lying posture to take a meal, to come down on the right side (left side with respect to the person lying on his/her back) floor 43 or to be held or carried on his/her back by a person standing at the right side of the bed, the cam pin 19 should be inserted into the left hole 18 of the lateral frame 18 beforehand as shown in FIGS. 6 and 7, and the screw shaft 12 should be rotated counterclockwise by the motor 10 to move the screw cylinder 13 forward. Then, first the cam roller 37, fitted to the waist supporting frame 21a through the bracket 35, is moved up by the cam 39. At the same time the cam roller 38, fitted to the back supporting frame 21b through the bracket 36, gets into contact with the front face of the cam 40, so that the supporting frames 21 and 21b are pivoted as shown in the operation processes shown in FIGS. 17 to 19 and the person on the bed is moved into the posture to take a meal or read a book as shown in FIGS. 22 and 23. To simply raise the person on the bed to such a posture, the cam pin 19 need not be inserted into the hole 18a or 18b. Next, when the motor 10 is further rotated to move the screw cylinder 13 forward, the cam pin 19 gets into contact with the displacing zone in the cam groove A of the left fixed cam 9a provided on the bed fixed frame 1, and the frame 16 on which the motor 10 is mounted and the pivoting frame 6 integrally fixed to the frame 16 pivots rightward (in the arrow E direction) with respect to the fixed frame 1 from the state shown in FIG. 13 to the state shown in FIG. 16 through the states shown in FIGS. 14 and 15. In the state shown in FIG. 15, during pivoting movement, the cam rollers 37 and 38 and the cams 39 and 40 are located as shown in FIG. 19. As the screw cylinder 13 is moved further forward, the pivoting frame 6 and the driving section, including the motor pivot approximately 45.degree. from the state shown in FIG. 15 to the state shown in FIG. 16, i.e. pivoted approximately 90.degree. from the initial position. During the second pivoting movement of about 45.degree., the positional relation between the cam rollers 37 and 38 and the cams 39 and 40 is changed from the state shown in FIG. 19 to the state shown in FIG. 21, while the back supporting frame 21b pivots slightly backward, the rear side of waist supporting frame 21a becomes slightly higher simultaneously, and, after this, the back supporting frame 21b stands up again, and, at the same time, the waist supporting frame 21 is set to the horizontal state, i.e. the lying person is finally set to the posture shown in FIG. 24 through the posture shown in FIG. 23.

The bed can be returned from the position shown in FIG. 24 to the original horizontal position by rotating the motor 10 clockwise (in the reverse direction to the above-mentioned direction). In this case, completely reverse operation to the above-mentioned is performed, so that the person is returned to the lying posture. To move the pivoting frame 6 reversely so that the person on the bed can get down at the opposite side of the bed, the cam pin 19 should be inserted in the other hole 18b to fit it into the cam groove B of the fixed cam 9b.

Accordingly, since waist supporting frame 21a and the back supporting frame 21b are operated as shown in FIGS. 19 to 21 as stated above during the operating processes of the front bed section 20a from FIGS. 23 to 24, the femur of a person on the bed near the waist, which is supported on the front of the waist supporting frame 12a, is slightly lifted a) to prevent his/her feet from being rubbed over the fixed rear bed section 20b while the front bed section is pivoting and b) to prevent the foot from twisting opposite to the pivoting direction by being caught by the fixed rear bed section 20b. At this time, if only the waist supporting frame 21a is lifted, the person on the bed is excessively bent and in pain. Therefore, this bed is designed so that the waist supporting frame 21a returns to the horizontal posture and stands up again after the back supporting frame 21b turns slightly backward. Accordingly, a person lying in the posture shown in FIG. 23 can raise his/her back and, finally, turn to the side of the bed to bring his/her feet onto the floor as shown in FIG. 24. Then, the pivoting handrails 31b, at the rear of the handrails 31, are operated as shown in FIG. 12 to pivot inward from above. The pivoting handrails 31b, therefore, come near the right and left hands of the person who wants to stand up from the posture shown in FIG. 24. Then, he/she can stand up easily by grasping the pivoting handrails 31b and sliding his/her body apart from the bed with the strength of his/her arms.

Also, when the end of the rod 28 has been connected to the bracket 22a of the protruding frame 22, the head supporting frame 21c is kept horizontal, therefore, as shown in FIGS. 23 and 24, the pillow 44 on the head supporting frame 21c is kept in place without falling even if the back supporting frame 21b is raised and pivoted.

An effect of this invention, as explained above, is that a head supporting frame is connected to the front of a back supporting frame so that the head supporting frame can be bent freely at the joint. A posture change-over means is designed so that the posture of the head supporting frame when the back supporting frame is raised and pivoted can be selected from two postures; a posture where the head supporting frame is kept horizontal and a posture where the head supporting frame and the back supporting frame form one plane. Therefore, in the latter case, the bed can be used in the same manner as previous beds capable of raising the upper body, and in the former case, a user can raise his/her upper body without dropping the pillow or articles even when he/she raises his/her back.