CN112168629B - Old-age-assisting anti-falling vehicle - Google Patents

Abstract

The invention discloses an anti-falling vehicle for the elderly, which comprises an upper end supporting component, an angle adjusting component, a bottom movement component and a seat component; the upper end supporting component is used for supporting the old people and preventing the old people from falling forwards, leftwards, rightwards and rearwards; the bottom motion assembly is used for driving the anti-falling car to move forwards and backwards; the angle adjusting assembly is arranged on the upper surface of the bottom moving assembly, the upper end of the angle adjusting assembly is fixedly connected with the lower surface of the upper end supporting assembly, and the angle adjusting assembly can rotate around the bottom moving assembly to drive the upper end supporting assembly to rotate; the anti-falling vehicle has the function of adjusting the gravity center and the function of preventing the old people from falling down through the mutual matching of the upper end supporting component, the angle adjusting component, the bottom moving component and the seat component.

Description

Old-age-assisting anti-falling vehicle

Technical Field

The invention relates to the technical field of an aging assisting device, in particular to an aging assisting anti-falling vehicle.

Background

In the current society, the number of solitary old people is continuously increased, various potential safety hazards can appear when the solitary old people walk at home, the solitary old people can cause serious injury to the bodies of the solitary old people after falling down, and a device is needed to ensure the safety of daily walking. The existing anti-falling device mainly comprises a crutch, anti-falling shoes and anti-falling protective clothing. The crutch can play a certain role in protection, but has no high safety coefficient; the anti-falling shoe has a gravity center adjusting portion, but it cannot secure the safety of the old; the anti-fall protective suit can ensure the safety protection of the old when falling down, but has no gravity center adjusting part. Therefore, a walking aid anti-falling device with the gravity center adjusting function and the safety protection function is urgently needed.

Disclosure of Invention

The invention aims to solve the defects and problems in the background art, and provides an anti-falling vehicle for helping the old. An anti-falling vehicle for the aged comprises an upper end supporting component, an angle adjusting component, a bottom motion component and a seat component; the upper end supporting component is used for supporting the old people and preventing the old people from falling forwards, leftwards, rightwards and rearwards; the bottom motion assembly is used for driving the anti-falling car to move forwards and backwards; the angle adjusting assembly is arranged on the upper surface of the bottom moving assembly, the upper end of the angle adjusting assembly is fixedly connected with the lower surface of the upper end supporting assembly, and the angle adjusting assembly can rotate around the bottom moving assembly to drive the upper end supporting assembly to rotate; the seat assembly is also mounted to the upper surface of the bottom motion assembly, and the seat assembly can be opened and closed according to the change in the center of gravity of the elderly person.

Further scheme is, upper end supporting component includes upper portion panel, support arm and back, and the quantity of support arm has two and installs in the both ends of upper portion panel, and the one end that upper portion panel was kept away from to the support arm is provided with the back that is used for supporting the old man back, be provided with back controller in the support arm, back controller is used for controlling the rotation and the locking of back.

Further scheme is, bottom motion subassembly includes driving motor, bottom panel, panel beating backup pad, drive wheel and universal wheel, and there are two panel beating backup pad's quantity, and the panel beating backup pad both ends buckle downwards and form the cavity, and the panel beating backup pad is installed in bottom panel's both ends, and the universal wheel is installed at bottom panel both ends, and the one end roll connection that the bottom panel was kept away from to the panel beating backup pad has the drive wheel, installs driving motor in the cavity of panel beating backup pad, and driving motor is used for driving the drive wheel rotation.

Further scheme is, angle adjusting part includes electric putter, supports pipe, supports the lower extreme of pipe and supporting the pipe and all rotates with bottom panel upper surface middle part to be connected, supports the pipe and all with upper panel fixed connection the upper end of supporting the pipe, supports the quantity of pipe and has two and set up in supporting the pipe both ends, electric putter installs in the upper surface of panel beating backup pad obliquely, electric putter and supports the pipe one-to-one, electric putter's flexible end and supports the pipe lower extreme and rotate to be connected.

Further scheme is, the seat subassembly includes steering wheel, rocker slider connecting rod, slider, bearing frame and section bar frame, and the last surface mounting of every panel beating backup pad has two section bar frames, is provided with the steering wheel between the section bar frame, and the recess is all seted up to the side around the section bar frame, and the bearing frame is installed to the recess bottom of section bar frame leading flank, and upper portion sliding connection has the slider in the recess of side about the section bar frame, rocker one end and bearing frame roll connection, and the rocker other end is connected with the rotation of rocker slider connecting rod, and the one end and the slider rotation of rocker are kept away from to the rocker slider connecting rod are connected, steering wheel can accurate control rocker rotation angle, drive rocker slider connecting rod upper surface mounting's thing to sit on and horizontal plane parallel.

Further scheme is, back controller includes handle, spring, dog, cam, motion pole, incomplete gear piece, gear and lug, motion pole both ends are fixedly connected with lug and incomplete gear piece respectively, the dog is run through at motion pole middle part, the spring housing is established on the motion pole, protruding portion fixed connection on spring one end and the motion pole, the spring other end and dog fixed connection, install the gear in the one end of keeping away from upper portion panel in the support arm, the gear is used for driving the back rotatory, the handle is used for controlling cam rotatory extrusion lug, drive motion pole to keeping away from gear one end motion, make incomplete gear piece break away from with the gear mutually, after the cam does not extrude the lug, the spring reset drives motion pole to the one end motion that is close to the gear, incomplete gear piece meshes with the gear.

The further scheme is that the seat is canvas, and the canvas has soft effect, and when the old people tip backwards, the old people can be supported, and the old people can be prevented from being injured.

Further scheme is, driving motor's output fixedly connected with motion transmission axle I, motion transmission axle I keeps away from rotary driving motor's one end interference fit has bevel gear I, insert in the middle of the drive wheel and be equipped with motion transmission axle II, motion transmission axle II is kept away from interference fit behind the panel beating backup pad having bevel gear II after the one end of bevel gear II runs through, and bevel gear I is connected with the meshing of bevel gear II.

Further, the upper surface of the supporting arm is provided with an elbow supporting block and a curved supporting plate.

Compared with the prior art, the invention has the beneficial effects that:

(1) The upper panel of upper end supporting component can prevent that the old man from falling forward, and the handrail frame of upper panel is convenient for the old man to promote anti-falling forward simultaneously, and the support arm can prevent that old man both sides from falling down, and elbow supporting shoe and the curved backup pad of installation on the support arm can be used for supporting old man's arm and elbow simultaneously, and the back can prevent that the old man from falling backward.

(2) The handle, the cam, the motion rod, the spring, the lug, the stop block, the incomplete gear block, the gear and the backrest are mutually matched, so that when the cam extrudes the lug to drive the motion rod to move towards one end far away from the gear, the incomplete gear block is separated from the gear, and the rotation arm can be rotated to adjust the angle of the backrest; after the cam extrudes the lug, the spring returns to drive the motion rod to move towards one end close to the gear, the incomplete gear block is meshed with the gear, and the backrest cannot rotate at the moment, so that the function of supporting the back of the old man can be achieved, and the old man is prevented from falling backwards.

(3) When the gravity center of the old people is unstable and the old people tip backwards, the driving motor is controlled to drive the anti-falling vehicle to move backwards, so that the gravity center of the anti-falling vehicle and the gravity center of the old people are projected on the same point, the effect of adjusting the gravity center of the anti-falling vehicle is achieved, and the anti-falling vehicle is prevented from tipping; meanwhile, the electric push rod is controlled to stretch to drive the supporting round pipe and the supporting square pipe to rotate forwards, so that the backrest pushes the old people to move forwards, the system is quickly balanced, the old people are prevented from falling down, and the function of protecting the walking safety of the old people is achieved.

(4) When the backrest does not support the old person, the steering engine through the control seat assembly can drive the metal plate connecting plate to rotate, so that the rocker is driven to rotate, the rocker drives the rocker slider connecting rod to rotate, the rocker slider connecting rod is enabled to rotate to form a seat after being horizontal to the horizontal plane, and at the moment, the rocker slider connecting rod and the profile frame form a stable triangular structure to support the old person, so that the safety of the old person is further protected.

Drawings

FIG. 1 is a first block diagram of an anti-roll cart according to the present invention;

FIG. 2 is a second block diagram of the anti-roll device of the present invention;

FIG. 3 is a block diagram of a back controller of the present invention;

FIG. 4 is a block diagram of a bottom motion assembly of the present invention;

FIG. 5 is a partially enlarged block diagram of FIG. 4A according to the present invention;

FIG. 6 is a block diagram of a seat assembly of the present invention;

Reference numerals: the bottom panel 1, the universal wheel 2, the sheet metal support plate 3, the driving motor 4, the driving wheel 5, the motion transmission shaft I6, the bevel gear I7, the motion transmission shaft II 8, the bevel gear II 9, the cavity 10, the steering engine 11, the connecting plate 12, the sheet metal connecting plate 13, the rocker 14, the steering engine fixing plate 15, the sliding block 16, the corner bracket 17, the section bar frame 18, the rocker sliding block connecting rod 19, the canvas 20, the section bar 21, the bearing pedestal 22, the support round tube 23, the electric push rod 24, the support block 25, the connecting block 26, the fixing block 27, the support square tube 28, the armrest frame 29, the upper panel 30, the support arm 31, the upper cover plate 32, the lower cover plate 33, the rotating arm 34, the backrest 35, the elbow support block 36, the curved support plate 37, the backrest controller 38, the handle 39, the cam 40, the spring 41, the moving rod 42, the stopper 43, the incomplete gear block 44, the gear 45, the controller 46 and the bump 47.

Detailed Description

The present invention will be described in further detail with reference to fig. 1 to 6.

Referring to fig. 1,2,4 and 5, an anti-roll cart for helping the old, comprising an upper end support assembly, an angle adjustment assembly, a seat assembly and a bottom motion assembly. The bottom motion subassembly includes bottom panel 1, universal wheel 2, sheet metal backup pad 3, driving motor 4, drive wheel 5, motion transmission axle I6, bevel gear I7, motion transmission axle II 8 and bevel gear II 9, the quantity of sheet metal backup pad 3 has two, the city is enclosed to the downward bending of sheet metal backup pad 3 both ends has cavity 10, two sheet metal backup pads 3 are in the same place with bottom panel 1 both ends fixed connection, universal wheel 2 is installed at bottom panel 1 both ends, driving motor 4 is installed in the one end cavity 10 that bottom panel 1 was kept away from to sheet metal backup pad 3, driving motor 4's output fixedly connected with motion transmission axle I6, bevel gear I7 is installed to the one end that driving motor 4 was kept away from to motion transmission axle I6, bevel gear I7 meshing is connected with bevel gear II 9, insert in the middle of bevel gear II 9 is equipped with motion transmission axle II 8, driving wheel 5 is installed to the one end that bevel gear II 9 was kept away from to motion transmission axle II 8, through the meshing transmission of bevel gear I7 and bevel gear II 9, driving motor 4 can drive driving wheel 5 rotation, the drive prevent that the drive wheel is front and back to move.

Referring to fig. 1, 2 and 6, in the embodiment, a seat assembly is installed in the middle of the upper surface of the sheet metal support plate 3, and the seat assembly comprises a steering engine 11, a connecting plate 12, a sheet metal connecting plate 13, a rocker 14, a steering engine fixing plate 15, a sliding block 16, a corner bracket 17, a profile frame 18, a rocker sliding block connecting rod 19, a canvas 20, a profile 21 and a bearing seat 22. The upper surface of every panel beating backup pad 3 is installed two section bar framves 18 through angle sign indicating number 17, section bar frame 18 top is in the same place through section bar 21 fixed connection, all set up flutedly on the side around section bar frame 18, install steering wheel fixed plate 15 between two section bar framves 18, install steering wheel 11 on the steering wheel fixed plate 15, the output fixedly connected with connecting plate 12 of steering wheel 11, steering wheel 11 can the rotation angle of accurate control connecting plate 12, the shape of connecting plate 12 is the several font, the one end middle part fixedly connected with panel beating connecting plate 13 of steering wheel 11 is kept away from to connecting plate 12, panel beating connecting plate 13 both ends fixedly connected with rocker 14, the bearing roll connection in rocker 14 bottom and the bearing frame 22, the recess lower extreme at section bar frame 18 front surface is installed to the bearing frame 22, the one end rotation that the rocker 14 kept away from the bearing frame 22 is connected with rocker slider connecting rod 19, the one end rotation that the rocker slider connecting rod 19 kept away from the rocker 14 is connected with slider 16, slider 16 sets up in the recess sliding connection of section bar frame 18 upper portion and section bar 18 left and right sides, install canvas 20 between the two rocker slider connecting rods 19. When the seat is used, the steering engine 11 drives the rocker 14 to rotate around the bearing seat 22, the rocker 14 drives the rocker slider connecting rods 19 to rotate, the rocker slider connecting rods 19 reach the preset position, canvas 20 mounted on the upper surfaces of the two rocker slider connecting rods 19 is parallel to the horizontal plane to form the seat, canvas 20 of the seat assembly on the two sheet metal supporting plates 3 are combined together, and at the moment, the rocker 14, the rocker slider connecting rods 19 and the profile frame 18 form a stable triangular structure; when the seat is not used, the steering engine 11 drives the rocker 14 to reversely rotate, so that the rocker slider connecting rod 19 is driven to move in the direction parallel to the section bar frame 18, and the seat is folded.

Referring to fig. 1 and 2, in this embodiment, an angle adjusting assembly is installed on the upper surface of one end of the sheet metal support plate 3 far away from the driving wheel 5 and the upper surface of the bottom panel 1, the angle adjusting assembly comprises a support circular tube 23, an electric push rod 24, a support block 25, a connecting block 26, a fixing block 27 and a support square tube 28, two electric push rods 24 are installed on the upper surface of one end of the sheet metal support plate 3 far away from the driving wheel 5 in an inclined manner, the middle part of the upper surface of the bottom panel 1 is rotatably connected with the support square tube 28 through the support block 25, the two ends of the upper surface of the bottom panel 1 are rotatably connected with the support circular tube 23 through the support block 25, the top ends of the support circular tube 23 and the support square tube 28 are fixedly connected with an upper end support assembly, the support square tube 28 plays a role in overall support, the telescopic ends of the electric push rod 24 are rotatably connected with the fixing block 27, the fixing block 27 is installed at one end of the connecting block 26, one end of the connecting block 26 far away from the fixing block 27 is fixedly connected with the support circular tube 23, and the electric push rod 24 is telescopically pulls the fixing block 27 so as to drive the support circular tube 23 to rotate around the support circular tube 25, thereby achieving the role of adjusting the angle of the upper end support assembly.

Referring to fig. 1, 2 and 3, in the present embodiment, the upper end supporting assembly includes a handrail frame 29, an upper panel 30, a supporting arm 31, a rotating arm 34, a backrest 35, an elbow supporting block 36, a curved supporting plate 37 and a backrest controller 38, the upper panel 30 is fixedly connected with one end of the supporting circular tube 23 and the supporting square tube 28 far from the bottom panel 1, the handrail frame 29 is installed in the middle of the upper panel 30, two supporting arms 31 are installed at both ends of the upper panel 30, one end of the supporting arm 31 far from the upper panel 30 extends horizontally to the direction of the driving wheel 5, and the supporting arms 31 are assembled together by bolting an upper cover plate 32 and a lower cover plate 33. The back controller 38 is installed in the support arm 31, the back controller 33 includes handle 39, cam 40, spring 41, motion pole 42, dog 43, lug 47, incomplete gear piece 44 and gear 45, handle 39 and cam 40 fixed connection, the rotation axis is inserted in the middle of the cam 40 and is connected with lower apron 33 roll, install motion pole 42 and dog 43 in the cavity that upper apron 32 and lower apron 33 enclose, be provided with annular bellying on the motion pole 42, the cover is equipped with spring 41 on the motion pole 42, spring 41 one end and dog 43 fixed connection, spring 41 other end and the annular bellying fixed connection on the motion pole 42, spring 41 is in compressed state, motion pole 42 one end fixedly connected with lug 47, motion pole 42 other end fixedly connected with incomplete gear piece 44. The support arm 31 is provided with the gear 45 in the one end that keeps away from the cam 40 inside, inserts in the middle of the gear 45 and is equipped with the rotation axis, installs the rotation arm 34 on the rotation axis of gear 45, and the one end that the rotation arm 34 kept away from the gear 45 is fixedly connected with back 35. The cam 40 can be driven to rotate by rotating the handle 39, when the cam 40 rotates to press the protruding block 47 to further compress the spring 41, and the motion rod 42 drives the incomplete gear block 44 to move towards one end close to the cam 40, the teeth of the incomplete gear block 44 are separated from the teeth of the gear 45, the gear 45 can rotate, the backrest 35 can rotate around the rotation axis of the gear 45, and at the moment, the angle of the backrest 35 can be adjusted by rotating the rotation arm 34; when the cam 40 does not press the bump 47, under the reset action of the spring 41, the incomplete gear block 44 moves towards one end far away from the cam 40, the teeth of the incomplete gear block 44 are meshed with those of the gear 45, the gear 45 cannot rotate, the backrest 35 cannot rotate around the rotation axis of the gear 45, the backrest 35 is fixed, and at the moment, the backrest 35 can play a certain supporting role to prevent the old people from falling backwards.

Further, the support arm 31 is close to upper surface mounting of upper panel 30 one end and has a controller 46, installs the singlechip in the controller 46, and electric putter 24, steering wheel 11 and driving motor 4 are connected in the output communication of singlechip, and the gyroscope has been integrated to the input communication of singlechip in the gyroscope, and gyroscope sensor and acceleration sensor are used for detecting the focus change of old man, and is common sense in the art.

The working principle of the invention is as follows: when the anti-falling device is used, the wearing gyroscope for the old people is positioned in a space surrounded by the upper panel 30, the supporting arm 31 and the backrest 35, the old people faces to the upper panel 30, the upper end supporting component plays a role in supporting the old people, the old people can grasp the armrest frame 29 by hands and push the anti-falling bicycle to move forward, the elbow supporting block 36 and the curved supporting plate 37 can be used for supporting arms and elbows of the old people, and the supporting angle of the backrest 35 can be adjusted by rotating the handle 39; when the gravity center of the old man is unstable and leans backwards, a gyroscope worn on the old man detects that the human body leans backwards, signals are sent to a singlechip in the controller, the singlechip controls a driving motor 4, and the driving motor 4 drives the anti-falling vehicle to move backwards, so that the gravity center of the anti-falling vehicle and the gravity center of the old man are projected on the same point, and the anti-falling vehicle is prevented from tilting; meanwhile, the electric push rod 24 is controlled to stretch to drive the supporting round pipe 23 and the supporting square pipe 28 to rotate forwards, and the backrest 35 connected with the upper panel 30 pushes the old people to move forwards, so that the system is quickly balanced, and the old people are prevented from falling down; if the backrest 35 does not support the old people, the steering engine 11 of the seat assembly can drive the sheet metal connecting plate 13 to rotate, so that the rocking rod 14 is driven to rotate, the rocking rod 14 drives the rocking rod sliding block connecting rod 19 to rotate, the rocking rod sliding block connecting rod 19 is enabled to rotate to be horizontal with the horizontal plane to form a seat, and at the moment, the rocking rod 14, the rocking rod sliding block connecting rod 19 and the section bar frame 18 form a stable triangular structure to support the old people.

The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims (4)

1. The utility model provides a help old anti-drop car which characterized in that: comprises an upper end supporting component, an angle adjusting component, a bottom moving component and a seat component;

the upper end supporting component is used for supporting the old people and preventing the old people from falling forwards, leftwards, rightwards and rearwards;

the bottom motion assembly is used for driving the anti-falling car to move forwards and backwards;

The angle adjusting assembly is arranged on the upper surface of the bottom moving assembly, the upper end of the angle adjusting assembly is fixedly connected with the lower surface of the upper end supporting assembly, and the angle adjusting assembly rotates around the bottom moving assembly to drive the upper end supporting assembly to rotate;

the seat assembly is also arranged on the upper surface of the bottom motion assembly, and the seat assembly opens and closes the seat according to the change of the gravity center of the aged;

The upper end support assembly comprises an upper panel (30), two support arms (31) and a backrest (35), wherein the number of the support arms (31) is two, the support arms are arranged at two ends of the upper panel (30), one end, far away from the upper panel (30), of each support arm (31) is provided with a backrest (35) for supporting the back of an old man, a backrest controller (38) is arranged in each support arm (31), and the backrest controller (38) is used for controlling the rotation and locking of the backrest (35);

The bottom motion assembly comprises a driving motor (4), a bottom panel (1), a metal plate supporting plate (3), driving wheels (5) and universal wheels (2), wherein the number of the metal plate supporting plates (3) is two, two ends of the metal plate supporting plate (3) are downwards bent to form a cavity (10), the metal plate supporting plate (3) is arranged at two ends of the bottom panel (1), the universal wheels (2) are arranged at two ends of the bottom panel (1), one end, far away from the bottom panel (1), of the metal plate supporting plate (3) is in rolling connection with the driving wheels (5), the driving motor (4) is arranged in the cavity (10) of the metal plate supporting plate (3), and the driving motor (4) is used for driving the driving wheels (5) to rotate;

The angle adjusting assembly comprises an electric push rod (24), supporting round pipes (23) and supporting round pipes (28), wherein the lower ends of the supporting round pipes (28) and the supporting round pipes (23) are respectively and rotatably connected with the middle part of the upper surface of the bottom panel (1), the upper ends of the supporting round pipes (28) and the supporting round pipes (23) are respectively and fixedly connected with the upper panel (30), the number of the supporting round pipes (23) is two and the two ends of the supporting round pipes (28), the electric push rod (24) is obliquely arranged on the upper surface of the sheet metal supporting plate (3), the electric push rod (24) corresponds to the supporting round pipes (23) one by one, and the telescopic ends of the electric push rod (24) are rotatably connected with the lower ends of the supporting round pipes (23);

The seat assembly comprises a steering engine (11), rocking bars (14), rocking bar sliding block connecting rods (19), sliding blocks (16), bearing blocks (22) and profile frames (18), wherein two profile frames (18) are arranged on the upper surface of each sheet metal supporting plate (3), the steering engine (11) is arranged between the profile frames (18), grooves are formed in the front side, the rear side, the left side and the right side of each profile frame (18), the bearing blocks (22) are arranged at the bottom ends of the grooves in the front side of each profile frame (18), the sliding blocks (16) are slidingly connected to the middle upper parts in the grooves in the left side and the right side of each profile frame (18), one end of each rocking bar (14) is in rolling connection with the corresponding bearing block (22), the other end of each rocking bar (14) is in rolling connection with the corresponding rocking bar sliding block connecting rod (19), one end, far away from each rocking bar (14), of each rocking bar sliding block connecting rod (19) is in rolling connection with the corresponding sliding block (16), the rotating angle of each rocking bar (14) is precisely controlled by the steering engine (11), and a seat arranged on the upper surface of each rocking bar connecting rod (19) is driven to be parallel to a horizontal plane.

The backrest controller (38) comprises a handle (39), a spring (41), a stop block (43), a cam (40), a moving rod (42), an incomplete gear block (44), a gear (45) and a lug (47), wherein the two ends of the moving rod (42) are fixedly connected with the lug (47) and the incomplete gear block (44) respectively, the middle part of the moving rod (42) penetrates through the stop block (43), the spring (41) is sleeved on the moving rod (42), one end of the spring (41) is fixedly connected with a protruding part on the moving rod (42), the other end of the spring (41) is fixedly connected with the stop block (43), a gear (45) is installed in one end, far away from the upper panel (30), of the supporting arm (31), the gear (45) is used for driving the backrest (35) to rotate, the cam (40) is rotationally extruded to extrude the lug (47), the moving rod (42) to one end far away from the gear (45), the incomplete gear block (44) is separated from the gear (45), after the cam (40) is not extruded, the spring (41) is reset to drive the moving rod (42) to move towards the gear (45) and the gear (45) to be meshed with the incomplete gear block (45).

2. The anti-roll cart for helping old people according to claim 1, wherein: the seat is canvas (20).

3. The anti-roll cart for helping old people according to claim 1, wherein: the output fixedly connected with motion transmission axle I (6) of driving motor (4), the one end interference fit that rotation driving motor (4) was kept away from to motion transmission axle I (6) has bevel gear I (7), insert in the middle of driving wheel (5) and be equipped with motion transmission axle II (8), interference fit has bevel gear II (9) behind the one end that bevel gear II (9) was kept away from to motion transmission axle II (8) runs through panel beating backup pad (3), and bevel gear I (7) and bevel gear II (9) meshing are connected.

4. The anti-roll cart for helping old people according to claim 1, wherein: the upper surface of the supporting arm (31) is provided with an elbow supporting block (36) and a curved supporting plate (37).