CN117179477A - Armrest capable of being adjusted in front-back stepless mode - Google Patents

Abstract

The invention discloses a handrail with stepless adjustment back and forth, which comprises a handrail panel (1), an upper cover plate (2), a lower cover plate (3) and an upright post (5); the handrail panel (1) is integrally formed by adopting polyurethane materials, a plurality of cambered surfaces are arranged on the top surface, and a dent is arranged on the bottom surface. When the rotation direction is adjusted, the armrest panel (1) is rotated by external force, one of the first positioning grooves (8.1) at each end of the base (8) is separated from the convex strips (9.2.2) at the two ends of the top plate (9.2), and one of the first positioning grooves (8.1) at each end is embedded into the corresponding position with the corresponding convex strip (9.2.2) again to realize angular positioning. The panel formed by integrally forming the polyurethane material is added at the top of the handrail, and the handrail can be adjusted according to the ergonomics of hands without an adjusting switch, so that the handrail is convenient for operators to use, and the handrail has a simple internal structure and good reliability.

Description

Armrest capable of being adjusted in front-back stepless mode

Technical Field

The invention relates to the technical field of office equipment, in particular to a handrail capable of being adjusted in a front-back stepless mode.

Background

Armrests are generally arranged on two sides of the office chair in a bilateral symmetry manner and are used for placing hands of a user, so that the hands are relaxed. The existing armrests are more and more complete in function, and have the functions of up-down adjustment, front-back adjustment, inclination angle adjustment and horizontal angle adjustment.

There is presently disclosed a handrail comprising a handrail upright and a handrail handle supported on the handrail upright and rotatable about an axis of rotation, the handrail handle being linearly movable relative to the handrail upright, a rotation mechanism for rotating the handrail handle being disposed substantially entirely inside the handrail upright. The basic idea is to arrange the rotation mechanism at least almost entirely or substantially inside the handrail upright. This means that the rotation mechanism is located inside the handrail structural element, which, although optionally movable in height, i.e. along a vertical line, is not movable in a horizontal direction, i.e. neither in a linear nor in a rotational movement. In other words, the rotation mechanism is not disposed exactly inside a handrail assembly, such as a handrail handle, that is mounted on a handrail upright and that is capable of horizontal movement. Instead, the rotation mechanism (by means of which the handrail handle can be rotated) is provided separately from the handrail handle, i.e. is placed in the handrail upright. The handrail of this structure above has the following drawbacks:

1. the top surface of the handrail is lack of a supporting surface, so that discomfort is brought to a user after the two hands are placed, and the top plate structure of the handrail is lack of a structure conforming to the human hand engineering.

2. In various adjustment, the adjustment switch is required to be turned to perform adjustment, so that certain inconvenience is brought to a user.

3. Although the multi-angle rotation can be realized, the gear meshing structure is adopted, the structure is complex, the later use needs regular maintenance, the internal structure is complex, and the durability is poor.

4. The upright post on the lower road of the armrest is provided with excessive adjusting structures and parts, so that the inner space is extruded, and the difficulty for up-and-down adjustment is increased.

Disclosure of Invention

The technical problem to be solved by the invention is to provide the front-back stepless regulation handrail which is formed by adding the panel formed by integrally molding the polyurethane material on the top of the handrail, can be regulated according to the ergonomics of hands without a regulating switch during regulation, is convenient for operators to use, and has simple internal structure and good reliability.

The technical scheme of the invention is that the handrail with the following structure is provided, and the handrail comprises a handrail panel, an upper cover plate, a lower cover plate and an upright post; the handrail panel is integrally formed by adopting polyurethane materials, a plurality of cambered surfaces are arranged on the top surface, and a concave is arranged on the bottom surface; the upper cover plate and the lower cover plate are fixed to form a handrail main body, a cavity is formed in the handrail main body, the bottom surface of the handrail panel is sunken to wrap the handrail main body, the bottom surfaces of the handrail main body and the handrail main body are flush, and the periphery of the upper cover plate extends outwards to form a supporting frame; the upright post stretches up and down and is provided with a positioning and adjusting mechanism, the top of the upright post is provided with an opening, a base is arranged at the opening and covers the opening, the top surface of the base is provided with a lug, and the cross section of the lug is rectangular; the handrail main body is internally provided with an adjusting disc and an adjusting block, the adjusting disc is positioned in a cavity of the handrail main body, the top of the adjusting disc is provided with a groove, the adjusting block is positioned in the groove of the adjusting disc, the lower cover plate is provided with a long hole, and the lower cover plate is arranged at the top of the base and the protruding block penetrates through the long hole; the adjusting block comprises a cylinder at the bottom and a top plate, wherein the top plate is bilaterally symmetrical, the end parts of the two ends are provided with second elastic pieces which swing along the up-down direction, the bottom surface of the second elastic pieces is provided with positioning convex strips, the base is rectangular, the inner bottom surfaces of the two ends are respectively provided with a plurality of parallel first positioning grooves which are arranged along the width direction, and all the first positioning grooves at the two ends of the base are positioned in the same circumference; the convex strips at the two ends of the top plate of the adjusting block are respectively embedded into a first positioning groove in the same end, so that the armrest main body can be positioned at a rotating angle in the horizontal direction; two outer side walls of the base along the length direction are respectively provided with a group of first elastic pieces, the first elastic pieces are formed by cutting U-shaped grooves in the side walls of the base, and the end parts of the free ends of the first elastic pieces protrude out of the side walls of the base; a group of positioning racks are arranged on two inner side walls of the lower cover plate along the length direction, the base is embedded in the adjusting block, and the end part of each first elastic piece is clung to the corresponding positioning rack, so that the armrest main body is positioned at the front-rear direction;

when the front-back direction is adjusted, the armrest panel is moved forwards or backwards by external force, so that the positioning racks on the two sides of the lower cover plate squeeze the end parts of the first elastic pieces, and the end parts of the first elastic pieces shrink inwards to enable the lower cover plate to be communicated with the upper cover plate and the armrest panel to move forwards or backwards; after moving, the end part of the first elastic sheet is embedded into a corresponding positioning rack to realize positioning;

when the rotation direction is adjusted, the armrest panel is rotated by external force, so that one of the first positioning grooves at each end of the base is separated from the convex strips at the two ends of the top plate, and the corresponding convex strip is embedded into the corresponding first positioning groove at each end again to realize angle positioning.

When the front-back direction is adjusted, the armrest main body slides forwards along the base, the cylinder is arranged outside the convex block, and the back surface of the cylinder abuts against the side surface of the rear end of the long hole to limit; the armrest main body slides backwards along the base, and the front surface of the cylinder abuts against the side surface of the front end of the long hole to limit. 3. A handrail with stepless adjustment of front and back as claimed in claim 1 or 2, wherein: the bottom surface of the second elastic piece is closely attached to the first positioning groove, and the convex strip moves to the first positioning groove on the edge and is embedded under the action of external force.

When the adjusting block rotates in the circumferential direction, the top plates at the two sides are tilted upwards, so that the convex strips can cross the partition plates between the adjacent first positioning grooves, and the bottoms of the convex strips are in an inverted triangle shape.

The regulating block is provided with a central hole and comprises two parts, wherein the regulating block is provided with a rectangular hole in the cylinder and a round hole in the top plate, and the rectangular hole in the cylinder is sleeved outside the lug, so that the regulating block and the round hole are circumferentially limited.

The positioning adjusting mechanism comprises an adjusting plate, a fixing plate, a connector and an armrest fixing plate, wherein the bottom end of the adjusting plate is provided with a bent positioning block, the fixing plate is provided with a plurality of positioning holes distributed up and down, the upright post moves up and down and is positioned by being embedded with one of the positioning holes through the positioning block, the positioning block is separated from the positioning holes by rotating the adjusting plate, so that the upright post slides up and down, after sliding, an elastic piece pushes the adjusting plate to enable the positioning block to be embedded with the corresponding positioning hole for positioning, the bottom end of the elastic piece is propped against the adjusting plate, and the top end of the elastic piece is propped against the base; the armrest fixing plate is arranged approximately perpendicular to the upright post.

The top plate of the adjusting block is diamond-shaped, and the raised strips are positioned on the bottom surfaces of the two ends with the minimum width, so that the elasticity of the end parts of the two ends is increased.

The center of the base is provided with a center hole, the cylinder penetrates through the center hole, and the cylinder is used as a rotation center shaft of the base.

The upper cover plate and the lower cover plate are provided with a first positioning structure in the front-back direction and a second positioning structure in the up-down direction; the first positioning structure comprises a first lock catch and a first lock hole, the first lock hole is positioned in the mounting block of the upper cover plate, the first lock catch is positioned in the mounting block and faces to the inner side, and the first lock catch is horizontally arranged and embedded in the first lock hole; the second positioning structure comprises a second lock catch and a third lock catch, the second lock catch is positioned in the upper cover plate, the third lock catch is positioned on the partition plate in the lower cover plate, and the second lock catch is locked with the upper barb and the lower barb of the third lock catch.

After adopting the structure, the invention has the following advantages:

1. because the handrail panel is integrally formed by adopting polyurethane materials, the top surface is provided with a plurality of cambered surfaces, the bottom surface is provided with a concave, and the polyurethane materials can be integrally manufactured into a structure which accords with human hand engineering, so that the handrail panel can be more suitable for the shape of hands; in addition, the top surface is provided with a plurality of cambered surfaces which are suitable for the protruding parts of the hands; the bottom surface is equipped with the recess and can imbed in the body of handrail, and the recess can increase the fixed intensity of connection between them moreover.

2. Moving the armrest panel forward or backward by an external force when being adjusted in the front-rear direction; when the rotation direction is adjusted, the armrest panel is rotated by external force, namely, the internal adjustment can be realized by the external force directly, and the adjusted position can be positioned by the internal positioning structure after the adjustment, so that convenience can be brought to a user.

3. The adjusting structure and the positioning structure are reliable in order receiving, the self elasticity of the elastic sheet is utilized to realize adjustment and positioning, the elastic sheet is deformed through external force during adjustment, and the elastic sheet is reset and positioned through the self of the elastic sheet during positioning after adjustment, so that the structure does not need later maintenance, and the internal structure is simple and has good reliability.

4. The regulating disk adopted by the structure is used as a reference for the front-back sliding of the lower cover plate when being adjusted front and back, the front-back sliding position of the lower cover plate is not influenced when the regulating disk rotates, and any position which is slid front and back can be adjusted through angle rotation without mutual influence.

5. The cylinder of the adjusting block adopted by the structure not only can be used as a reference for rotation of the adjusting disk, but also can be used for positioning the limit position of the front-back sliding position; the other two second elastic sheets can also position the position of angular rotation.

6. The parts of fore-and-aft regulation and the parts of angle regulation are highly integrated, and all are located on the top of stand, do not occupy the space that utilizes inside, have the altitude mixture control spare part installation in utilizing the stand, and it is also more convenient when the installation moreover.

Drawings

Fig. 1 is an exploded view of the present invention.

Fig. 2 is a split schematic view of the armrest body of the present invention.

Fig. 3 is a split schematic view of the inside of the lower cover plate of the present invention.

Fig. 4 is a schematic cross-sectional view of the present invention.

Fig. 5 is a schematic view of the lower cover plate of the present invention.

Fig. 6 is a schematic view of a conditioning disk of the present invention.

Fig. 7 is a schematic view of a bump of the present invention.

Fig. 8 is a schematic view showing the upper and lower cover plates of the present invention in a separated state.

Fig. 9 is an enlarged schematic view of a portion a of fig. 4.

The figure shows:

1. the handrail panel, 2, the upper cover plate, 2.1, the support frame, 3, the lower cover plate, 3.1, the slot hole, 3.2, the positioning rack, 3.3, the first hasp, 3.4, the third hasp, 4, the handrail main part, 5, stand, 6, the base, 7, the lug, 8, the regulating plate, 8.1, first constant head tank, 8.2, first shell fragment, 8.3, the centre bore, 9, the regulating block, 9.1, the cylinder, 9.2, the roof, 9.2.1, the second shell fragment, 9.2.2, the sand grip, 10, the regulating plate, 11, the fixed plate, 12, the connector, 13, the handrail fixed plate.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1 to 9, the handrail with stepless adjustment back and forth of the invention comprises a handrail panel 1, an upper cover plate 2, a lower cover plate 3 and a stand column 5.

The handrail panel 1 is integrally formed by polyurethane materials, a plurality of cambered surfaces are arranged on the top surface, and a dent is arranged on the bottom surface. As shown in fig. 1 and 2, the top surface of the armrest panel 1 has a large arc, simulates the shape of a human hand to three-dimensionally model, and then is molded. The bottom surface is provided with a dent, and the dent is used for embedding the lower cover plate 3 to fix the lower cover plate and the lower cover plate.

As shown in fig. 1 and 2, the upper cover plate 2 and the lower cover plate 3 are fixed to form a handrail main body 4, a cavity is arranged in the handrail main body 4, and components for front and back adjustment and components for angle rotation are arranged in the cavity. The concave part of the bottom surface of the handrail panel 1 wraps the handrail main body 4 and the bottom surfaces of the handrail main body and the handrail main body are flush, and the periphery of the upper cover plate 2 extends outwards to form a supporting frame 2.1. The supporting frame 2.1 is a circle along the outer side of the upper cover plate 2, and is embedded into the annular groove of the handrail panel 1 after being assembled, so that the connection strength of the supporting frame and the handrail panel is increased, and meanwhile, the strength of the handrail panel 1 can be also manufactured.

The top opening of the upright post 5 is provided with a base 6 at the opening and covers the opening, the top surface of the base 6 is provided with a protruding block 7, and the cross section of the protruding block 7 is rectangular.

Be equipped with adjustment disk 8 and regulating block 9 in the handrail main part 4, adjustment disk 8 is located the cavity of handrail main part 4, the top of adjustment disk 8 is equipped with the recess, regulating block 9 is located the recess of adjustment disk 8, be equipped with slot hole 3.1 on the lower apron 3, lower apron 3 is established at the top of base 6 and lug 7 passes slot hole 3.1.

As shown in fig. 7, the adjusting block 9 includes a cylinder 9.1 at the bottom and a top plate 9.2, the top plate 9.2 is bilaterally symmetrical, two end portions are provided with second elastic pieces 9.2.1 swinging along the up-down direction, the bottom surface of the second elastic pieces 9.2.1 is provided with a positioning convex strip 9.2.2, the base 8 is rectangular, the inner bottom surfaces of the two ends are respectively provided with a plurality of parallel first positioning grooves 8.1 arranged along the width direction, and all the first positioning grooves 8.1 at the two ends of the base 8 are positioned in the same circumference; the convex strips 9.2.2 at the two ends of the top plate 9.2 of the adjusting block 9 are respectively embedded into one of the first positioning grooves 8.1 in the same end, so that the rotation angle positioning of the armrest main body 4 in the horizontal direction is realized. The top plate 9.2 of the adjusting block 9 has a diamond shape, and the convex strips 9.2.2 are positioned on the bottom surfaces of the two ends with the smallest width, so that the elasticity of the end parts of the two ends is increased.

The bottom surface of the second elastic piece 9.2.1 is spaced from the inner bottom surface of the base 8, the bottom surface of the convex strip 9.2.2 is tightly attached to the first positioning groove 8.1, and the convex strip 9.2.2 moves to the first positioning groove 8.1 on the side and is embedded under the action of external force.

When the adjusting block 9 circumferentially rotates, the top plates 9.2 on two sides are tilted upwards, so that the convex strips 9.2.2 can cross the partition plates between the adjacent first positioning grooves 8.1, and the bottoms of the convex strips 9.2.2 are in an inverted triangle shape.

The adjusting block 9 is provided with a central hole and comprises two parts, wherein the rectangular hole is positioned in the cylinder 9.1, the round hole is positioned in the top plate 9.2, and the rectangular hole in the cylinder 9.1 is sleeved outside the protruding block 7, so that the two parts are circumferentially limited.

As shown in fig. 6, a set of first elastic pieces 8.2 are respectively arranged on two outer side walls of the base 8 along the length direction, the first elastic pieces 8.2 are formed by cutting U-shaped grooves on the side walls of the base 8, and the end parts of the free ends of the first elastic pieces 8.2 are protruded out of the side walls of the base 8; a group of positioning racks 3.2 are arranged on two inner side walls of the lower cover plate 3 along the length direction, the base 8 is embedded in the adjusting block 9, and the end part of each first elastic sheet 8.2 is tightly attached to the corresponding positioning rack 3.2, so that the handrail main body 4 is positioned at the front-rear direction; the center of the base 8 is provided with a center hole 8.3, the cylinder 9.1 penetrates through the center hole 8.3, and the cylinder 9.1 serves as a rotation center shaft of the base 8.

As shown in fig. 4, the upright 5 stretches up and down and is provided with a positioning adjusting mechanism, the positioning adjusting mechanism comprises an adjusting plate 10, a fixing plate 11, a connector 12 and an armrest fixing plate 13, a curved positioning block is arranged at the bottom end of the adjusting plate 10, the fixing plate 11 is provided with a plurality of positioning holes distributed up and down, the upright 5 moves up and down and is positioned by being embedded into one of the positioning holes through the positioning block, the adjusting plate 10 is rotated to separate the positioning block from the positioning hole so that the upright 5 slides up and down, and after sliding, an elastic piece pushes the adjusting plate 10 to enable the positioning block to be embedded into the corresponding positioning hole for positioning, the bottom end of the elastic piece is propped against the adjusting plate 10, and the top end of the elastic piece is propped against the base 6; the armrest fixing plate 13 is provided substantially perpendicularly to the upright 5.

As shown in fig. 8, the upper cover plate 2 and the lower cover plate 3 are provided with a first positioning structure in the front-rear direction and a second positioning structure in the up-down direction; the first positioning structure comprises a first lock catch 3.3 and a first lock hole, the first lock hole is positioned in a mounting block 2.2 of the upper cover plate 2, the first lock catch 3.3 is positioned in the mounting block 2.2 and faces to the inner side, and the first lock catch 3.3 is horizontally arranged and embedded in the first lock hole; the second positioning structure comprises a second lock catch 2.3 and a third lock catch 3.4, wherein the second lock catch 2.3 is positioned in the upper cover plate 2, the third lock catch 3.4 is positioned on a partition plate in the lower cover plate 3, and the second lock catch 2.3 and the third lock catch 3.4 are locked by an upper barb and a lower barb.

After the convex strips 9.2.2 are embedded into the first positioning groove 8.1, a distance is arranged between the bottom surface of the convex strips 9.2.2 and the bottom surface of the first positioning groove 8.1, two side walls of the convex strips 9.2.2 are clung to two side walls of the first positioning groove 8.1, so that the convex strips 9.2.2 are embedded more firmly, shaking is avoided after the convex strips are clung to the bottom surface of the first positioning groove 8.1, and the silence is better.

The adjustment process comprises the following steps:

when the front-back direction is adjusted, the armrest panel 1 is moved forwards or backwards by external force, so that the positioning racks 3.2 at the two sides of the lower cover plate 3 squeeze the end parts of the first elastic pieces 8.2, and the end parts of the first elastic pieces 8.2 shrink inwards to enable the lower cover plate 3 to be communicated with the upper cover plate 2 and the armrest panel 1 to move forwards or backwards; after moving, the end part of the first elastic sheet 8.2 is embedded into the corresponding positioning rack 3.2 to realize positioning; when the front-back direction is adjusted, the armrest main body 4 slides forwards along the base 6, and the back surface of the lug 7 abuts against the side surface of the rear end of the long hole 3.1 to limit; the armrest body 4 slides backwards along the base 6, and the front surface of the lug 7 abuts against the side surface of the front end of the long hole 3.1 to limit.

When the rotation direction is adjusted, the armrest panel 1 is rotated by external force, so that one of the first positioning grooves 8.1 at each end of the base 8 is separated from the convex strips 9.2.2 at the two ends of the top plate 9.2, and one of the first positioning grooves 8.1 at each end is embedded into the corresponding position with the corresponding convex strip 9.2.2 again to realize angle positioning.

Claims (10)

1. The handrail comprises a handrail panel (1), an upper cover plate (2), a lower cover plate (3) and an upright post (5); the handrail panel (1) is integrally formed by adopting polyurethane materials, a plurality of cambered surfaces are arranged on the top surface, and a concave is arranged on the bottom surface; the upper cover plate (2) and the lower cover plate (3) are fixed to form a handrail main body (4), a cavity is formed in the handrail main body (4), the bottom surface of the handrail panel (1) is sunken to wrap the handrail main body (4) and the bottom surfaces of the handrail main body and the handrail main body are flush, and the periphery of the upper cover plate (2) extends outwards to form a supporting frame (2.1); the stand column (5) stretches up and down and is provided with a positioning and adjusting mechanism, the top of the stand column (5) is provided with an opening, a base (6) is arranged at the opening and covers the opening, the top surface of the base (6) is provided with a lug (7), and the cross section of the lug (7) is rectangular; an adjusting disc (8) and an adjusting block (9) are arranged in the handrail main body (4), the adjusting disc (8) is positioned in a cavity of the handrail main body (4), a groove is formed in the top of the adjusting disc (8), the adjusting block (9) is positioned in the groove of the adjusting disc (8), a long hole (3.1) is formed in the lower cover plate (3), the lower cover plate (3) is arranged at the top of the base (6), and the protruding block (7) penetrates through the long hole (3.1); the adjusting block (9) comprises a cylinder (9.1) at the bottom and a top plate (9.2), the top plate (9.2) is bilaterally symmetrical, second elastic pieces (9.2.1) swinging along the up-down direction are arranged at the end parts of the two ends of the top plate, positioning convex strips (9.2.2) are arranged on the bottom surface of the second elastic pieces (9.2.1), the base (8) is rectangular, a plurality of parallel first positioning grooves (8.1) are respectively arranged on the inner bottom surfaces of the two ends of the base (8), and all the first positioning grooves (8.1) at the two ends of the base (8) are positioned in the same circumference; the convex strips (9.2.2) at the two ends of the top plate (9.2) of the regulating block (9) are respectively embedded into one first positioning groove (8.1) in the same end, so that the rotation angle positioning of the armrest main body (4) in the horizontal direction is realized;

two outer side walls of the base (8) along the length direction are respectively provided with a group of first elastic pieces (8.2), the first elastic pieces (8.2) are formed by cutting U-shaped grooves in the side walls of the base (8), and the end parts of the free ends of the first elastic pieces (8.2) protrude out of the side walls of the base (8); a group of positioning racks (3.2) are arranged on two inner side walls of the lower cover plate (3) along the length direction, the base (8) is embedded in the adjusting block (9), and the end part of each first elastic piece (8.2) is tightly attached to the corresponding positioning rack (3.2), so that the handrail main body (4) is positioned at the front-rear direction;

when the front-back direction is adjusted, the armrest panel (1) is moved forwards or backwards by external force, so that the positioning racks (3.2) on the two sides of the lower cover plate (3) squeeze the end part of the first elastic piece (8.2), and the end part of the first elastic piece (8.2) is contracted inwards to enable the lower cover plate (3) to be communicated with the upper cover plate (2) and the armrest panel (1) to move forwards or backwards; after moving, the end part of the first elastic sheet (8.2) is embedded into the corresponding positioning rack (3.2) to realize positioning;

when the rotation direction is adjusted, the armrest panel (1) is rotated by external force, one of the first positioning grooves (8.1) at each end of the base (8) is separated from the convex strips (9.2.2) at the two ends of the top plate (9.2), and one of the first positioning grooves (8.1) at each end is embedded into the corresponding position with the corresponding convex strip (9.2.2) again to realize angular positioning.

2. A back and forth stepless adjustment handrail as claimed in claim 1, wherein: when the front-back direction is adjusted, the armrest main body (4) slides forwards along the base (6), and the back surface of the lug (7) is propped against the side surface of the rear end of the long hole (3.1) to limit; the armrest main body (4) slides backwards along the base (6), and the front surface of the lug (7) abuts against the side surface of the front end of the long hole (3.1) to limit.

3. A handrail with stepless adjustment of front and back as claimed in claim 1 or 2, wherein: the bottom surface of the second elastic piece (9.2.1) is spaced from the inner bottom surface of the base (8), the bottom surface of the convex strip (9.2.2) is tightly attached to the first positioning groove (8.1), and the convex strip (9.2.2) moves to the first positioning groove (8.1) on the edge and is embedded under the action of external force.

4. A front-to-back stepless adjustment handrail as claimed in claim 3, wherein: when the adjusting block (9) circumferentially rotates, the top plates (9.2) at two sides tilt upwards, so that the convex strips (9.2.2) can cross the partition plates between the adjacent first positioning grooves (8.1), and the bottoms of the convex strips (9.2.2) are in an inverted triangle shape.

5. A back and forth stepless adjustable handrail as claimed in claim 1, 2 or 4, wherein: the adjusting block (9) is provided with a central hole and comprises two parts, wherein the rectangular hole is positioned in the cylinder (9.1), the round hole is positioned in the top plate (9.2), and the rectangular hole in the cylinder (9.1) is sleeved outside the lug (7) so that the two parts are circumferentially limited.

6. A back and forth stepless adjustment handrail as claimed in claim 5, wherein: the positioning adjusting mechanism comprises an adjusting plate (10), a fixing plate (11), a connector (12) and an armrest fixing plate (13), wherein a bent positioning block is arranged at the bottom end of the adjusting plate (10), a plurality of positioning holes distributed up and down are formed in the fixing plate (11), the upright post (5) moves up and down and is positioned by being embedded into one of the positioning holes through the positioning block, the adjusting plate (10) is rotated to enable the positioning block to be separated from the positioning hole so that the upright post (5) slides up and down, an elastic piece pushes the adjusting plate (10) to enable the positioning block to be embedded into a corresponding positioning hole for positioning after sliding, the bottom end of the elastic piece is propped against the adjusting plate (10), and the top end of the elastic piece is propped against the base (6); the armrest fixing plate (13) is arranged approximately perpendicular to the upright post (5).

7. A handrail with stepless adjustment of front and back as claimed in claim 1 or 2, wherein: the top plate (9.2) of the adjusting block (9) is diamond-shaped, and the raised strips (9.2.2) are positioned on the bottom surfaces of the two ends with the smallest width, so that the elasticity of the end parts of the two ends is increased.

8. A back and forth stepless adjustment handrail as claimed in claim 1, wherein: the center of the base (8) is provided with a center hole (8.3), the cylinder (9.1) penetrates through the center hole (8.3), and the cylinder (9.1) is used as a rotation center shaft of the base (8).

9. A back and forth stepless adjustment handrail as claimed in claim 1, wherein: the upper cover plate (2) and the lower cover plate (3) are provided with a first positioning structure in the front-back direction and a second positioning structure in the up-down direction; the first positioning structure comprises a first lock catch (3.3) and a first lock hole, the first lock hole is positioned in a mounting block (2.2) of the upper cover plate (2), the first lock catch (3.3) is positioned in the mounting block (2.2) and faces to the inner side, and the first lock catch (3.3) is horizontally arranged and embedded in the first lock hole; the second positioning structure comprises a second lock catch (2.3) and a third lock catch (3.4), wherein the second lock catch (2.3) is positioned in the upper cover plate (2), the third lock catch (3.4) is positioned on a partition plate in the lower cover plate (3), and the second lock catch (2.3) is locked with the third lock catch (3.4) through an upper barb and a lower barb.

10. A back and forth stepless adjustment handrail as claimed in claim 1, wherein: after the raised strips (9.2.2) are embedded into the first positioning groove (8.1), a space is arranged between the bottom surface of the raised strips (9.2.2) and the bottom surface of the first positioning groove (8.1), and two side walls of the raised strips (9.2.2) are clung to two side walls of the first positioning groove (8.1).