CN109938931B

CN109938931B - Stair stretcher for medical field

Info

Publication number: CN109938931B
Application number: CN201910303782.9A
Authority: CN
Inventors: 张楼锋
Original assignee: Individual
Current assignee: Zhuji Tiantong Chemical Fiber Co ltd
Priority date: 2018-06-19
Filing date: 2018-06-19
Publication date: 2020-06-30
Anticipated expiration: 2038-06-19
Also published as: CN108743055A; CN109938931A; CN108743055B

Abstract

The invention belongs to the technical field of stretchers, and particularly relates to a stair stretcher for the medical field, which comprises a stretcher fixing plate, a first adjusting mechanism, a second adjusting mechanism, an unlocking plate sliding chute, a second guide groove, a pressing plate, a first rack, a second rack, a synchronizing mechanism and the like, wherein the swinging plates in the first adjusting mechanism and the second adjusting mechanism are adjusted to adapt to different conditions: firstly, when the stretcher transports a patient on a horizontal road, the swinging plate is in a horizontal state, and the same effect as that of a common simple stretcher is achieved. Second, when the stretcher transported the patient between the stair, four swing boards all were in vertical state, and two handles of stretcher one side are located the stretcher upside, and two handles of stretcher opposite side are located the stretcher downside, can guarantee like this that the patient on the stretcher can be steadily transported between the stair of altitude and depression. The design of the synchronizing mechanism and the two pressing plates reduces the cooperative fit among users, and increases the convenience of use of the stretcher.

Description

Stair stretcher for medical field

Technical Field

The invention belongs to the technical field of stretchers, and particularly relates to a stair stretcher for the medical field.

Background

Conventional simple medical stretchers are currently in widespread use in the context of transporting patients. For a high-rise building with an elevator in a city, the common medical stretcher can convey patients by utilizing different floors of the elevator; because the elevator is stable to move up and down, when a patient is transported in a high-rise building with the elevator, the common medical stretcher can be fully competent for the transportation task; however, in the case of a small high-rise building without an elevator, once a patient is injured and must be transported by a common medical stretcher, the common medical stretcher is prone to tilt during the patient transportation process in a staircase, and the patient on the stretcher may slip off the stretcher to cause secondary injury. In order to ensure that the stretcher can be always in a horizontal state when the stretcher is used for transporting patients in a staircase and prevent the patients from sliding off the stretcher, the medical stretcher for transporting the patients in the staircase needs to be designed.

The invention designs a stair stretcher for the medical field to solve the problems.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention discloses a stair stretcher for the medical field, which is realized by adopting the following technical scheme.

In the description of the present invention, it should be noted that the terms "inside", "below", "upper" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the present invention usually place when using, and are only used for convenience of description and simplification of description, but do not indicate or imply that the devices or elements indicated must have a specific orientation, be constructed in a specific orientation or be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

The utility model provides a stair stretcher that medical field used which characterized in that: the stretcher comprises a stretcher fixing plate, stretcher cloth, a first stretcher side plate, a second stretcher side plate, a first adjusting mechanism, a second adjusting mechanism, a sliding groove, a third guide groove, an unlocking plate sliding groove, a second guide groove, a pressing plate, a first rack, a second rack, a first supporting block, a second supporting block, a rack sliding groove, a shaft hole, a rack guide hole and a synchronizing mechanism; wherein, a stretcher cloth is arranged between the two stretcher fixing plates; the first stretcher side plate and the second stretcher side plate are respectively arranged at two ends of the stretcher fixing plate.

The structure and the mounting structure of first stretcher curb plate and second stretcher curb plate are the same, to first stretcher curb plate: the side surface of the first stretcher side plate, which is far away from the stretcher cloth, is symmetrically provided with two sliding grooves; two third guide grooves are symmetrically formed in two sides of each sliding groove; two unlocking plate sliding grooves are symmetrically formed in the end faces of the two ends of the first stretcher side plate; each unlocking plate sliding groove is communicated with the corresponding sliding groove; a second guide groove is formed in the side face of each unlocking plate sliding groove; the first adjusting mechanism and the second adjusting mechanism are respectively arranged in the two sliding grooves; the middle part of the first stretcher side plate is provided with a rack sliding groove; the middle position of the side surface of the rack sliding chute is provided with a shaft hole; the rack sliding groove is respectively communicated with the two sliding grooves; a first supporting block is arranged on the top groove surface of the sliding groove provided with the first adjusting mechanism; a second supporting block is arranged on the bottom groove surface of the sliding groove provided with the second adjusting mechanism; the first supporting block and the second supporting block are close to the rack sliding groove; the first supporting block and the second supporting block are both provided with through rack guide holes; one end of the first rack is arranged on the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is installed on the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove.

The first adjusting mechanism in the first stretcher side plate is opposite to the first adjusting mechanism in the second stretcher side plate; the second adjustment mechanism in the first stretcher side plate is opposite to the second adjustment mechanism in the second stretcher side plate; the first and second adjustment mechanisms are identical.

For both platens: one end of a press plate is connected with a first adjusting mechanism in the first stretcher side plate, and the other end of the press plate is connected with a first adjusting mechanism in the second stretcher side plate; one end of the other pressing plate is connected with the second adjusting mechanism in the first stretcher side plate, and the other end of the other pressing plate is connected with the second adjusting mechanism in the second stretcher side plate.

The two stretcher fixing plates are positioned between the two pressing plates.

The first adjusting mechanism comprises a sliding block, a third guide block, a second fixed block, a limiting block spring, a limiting block sliding groove, an unlocking plate, a second guide block, a second spring, a limiting groove, a ring sleeve, a limiting disc, a limiting strip-shaped plate, a first fixed block, a handle, a swinging plate, a fixed rod, a containing groove, a short inclined plane, a long inclined plane, a fillet, a limiting tooth, a first guide block, a first spring, a first guide groove and a sliding through groove, wherein the sliding block is arranged in the corresponding sliding groove in a sliding fit manner; two third guide blocks are symmetrically arranged on two sides of the sliding block; the two third guide blocks are respectively arranged in the two third guide grooves in a sliding fit manner; one end of the fixed rod is arranged on the sliding block, and the other end of the fixed rod is provided with a limiting disc; the fixed rod is vertical to the first stretcher side plate; a plurality of limiting teeth are uniformly distributed on the outer circular surface of the limiting disc along the circumferential direction; the ring sleeve is nested on the fixed rod and is positioned between the sliding block and the limiting disc; one end of the swinging plate is arranged on the outer circular surface of the ring sleeve; the handle and the first fixed block are both arranged on the side surface of the swinging plate far away from the sliding block; the handle is positioned at one end of the swinging plate far away from the ring sleeve, and the first fixed block is positioned between the limiting disc and the handle; a through sliding through groove is formed in the first fixing block; two first guide grooves are symmetrically formed in the two sides of the sliding through groove; the limiting strip-shaped plate is arranged in the sliding through groove in a sliding fit mode, and two ends of the limiting strip-shaped plate extend out of the sliding through groove; two first guide blocks are symmetrically arranged on two sides of the limiting strip-shaped plate; the two first guide blocks are respectively positioned in the two first guide grooves; the first guide block slides in the first guide groove; one ends of the two first springs are respectively arranged on the two first guide blocks, and the other ends of the two first springs are respectively arranged on the groove surfaces of the two first guide grooves; the two first springs are respectively positioned in the two first guide grooves; one end of the limiting strip-shaped plate is matched with the limiting teeth on the limiting disc.

The side surface of the sliding block is provided with an accommodating groove; a limiting block sliding groove is formed in the top groove surface of the accommodating groove; the limiting block is slidably arranged in the limiting block sliding groove; one end of the limiting block spring is arranged on the limiting block, and the other end of the limiting block spring is arranged on the groove surface of the limiting block sliding groove; one end of the limiting block, which is far away from the limiting block spring, is provided with a short inclined plane and a long inclined plane; a second fixed block is arranged on the side groove surface of the sliding groove with the unlocking plate sliding groove; a limiting groove is formed in the upper plate surface of the second fixing block; the unlocking plate is arranged in the unlocking plate sliding groove in a sliding fit mode, and two ends of the unlocking plate extend out of the unlocking plate sliding groove; the second guide block is arranged on the unlocking plate; the second guide block is positioned in the second guide groove; the second guide block slides in the second guide groove; one end of the second spring is arranged on the second guide block, and the other end of the second spring is arranged on the groove surface of the second guide groove; the second spring is located in the second guide groove.

For the first adjustment structure: the limiting block is matched with a limiting groove on the second fixing block; the second fixed block is matched with the accommodating groove; one end of the unlocking plate is matched with the long inclined plane on the limiting block.

To first adjustment mechanism, second adjustment mechanism, first rack and second rack in the first stretcher side plate: one end of the first rack is arranged on the sliding block of the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is installed on the sliding block of the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove.

To first adjustment mechanism, second adjustment mechanism, first rack and second rack in the second stretcher curb plate: one end of the first rack is arranged on the sliding block of the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is installed on the sliding block of the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove.

The two pressing plates are as follows: one end of one pressing plate is connected with an unlocking plate of a first adjusting mechanism in the first stretcher side plate, and the other end of the pressing plate is connected with an unlocking plate of a first adjusting mechanism in the second stretcher side plate; one end of the other pressing plate is connected with an unlocking plate of the second adjusting mechanism in the first stretcher side plate, and the other end of the other pressing plate is connected with an unlocking plate of the second adjusting mechanism in the second stretcher side plate.

The synchronous mechanism is arranged on the first stretcher side plate, the stretcher fixing plate and the second stretcher side plate; a first rack and a second rack in the first stretcher side plate are matched with the synchronous mechanism; the first rack and the second rack in the second stretcher side plate are matched with the synchronizing mechanism.

The synchronizing mechanism comprises a first change gear, a first rotating shaft, a first bevel gear, a second rotating shaft, a third fixed block, a third bevel gear, a fourth bevel gear, a third rotating shaft, a fourth fixed block, a fifth bevel gear, a sixth bevel gear, a fifth fixed block, a seventh bevel gear, an eighth bevel gear, a fourth rotating shaft, a fifth rotating shaft and a second change gear, wherein the first rotating shaft is arranged in a shaft hole at a rack sliding groove of the first stretcher side plate through a bearing, and two ends of the first rotating shaft extend out of the shaft hole; one end of the first rotating shaft is provided with a first change gear, and the other end of the first rotating shaft is provided with a first bevel gear; the first change gear is positioned in the rack sliding groove of the first stretcher side plate; the third fixing block is arranged on the first stretcher side plate; the third fixing block is provided with a through round hole; the second rotating shaft is arranged in a round hole of the third fixed block through a bearing, and two ends of the second rotating shaft penetrate through the third fixed block; one end of the second rotating shaft is provided with a second bevel gear, and the other end of the second rotating shaft is provided with a third bevel gear; the first bevel gear is meshed with the second bevel gear; the fourth fixed block is arranged on the corresponding stretcher fixed plate; the fourth fixed block is provided with a through round hole; the third rotating shaft is arranged in a round hole of the fourth fixed block through a bearing, and two ends of the third rotating shaft penetrate through the fourth fixed block; one end of the third rotating shaft is provided with a fourth bevel gear, and the other end of the third rotating shaft is provided with a fifth bevel gear; the third bevel gear is meshed with the fourth bevel gear; the fifth fixing block is arranged on the second stretcher side plate; the fifth fixed block is provided with a through round hole; the fourth rotating shaft is arranged in a round hole of the fifth fixing block through a bearing, and two ends of the fourth rotating shaft penetrate through the fifth fixing block; one end of the fourth rotating shaft is provided with a sixth bevel gear, and the other end of the fourth rotating shaft is provided with a seventh bevel gear; the fifth bevel gear is meshed with the sixth bevel gear; the fifth rotating shaft is arranged in a shaft hole at the rack sliding groove of the second stretcher side plate through a bearing, and two ends of the fifth rotating shaft extend out of the shaft hole; one end of the fifth rotating shaft is provided with a second steering gear, and the other end of the fifth rotating shaft is provided with an eighth bevel gear; the second change gear is positioned in the rack sliding groove of the first stretcher side plate; the seventh bevel gear is meshed with the eighth bevel gear.

A first rack and a second rack in the first stretcher side plate are respectively meshed with a first change gear; and a first rack and a second rack in the second stretcher side plate are respectively meshed with the second change gear.

As a further improvement of the technology, the side surfaces of the limiting teeth are parallel to the side surfaces of the adjacent limiting teeth. Such design lies in, when the one end of spacing strip template was located between two adjacent spacing tooth, the both sides of spacing strip template and the side of two spacing tooth laminate completely, and two spacing tooth can be spacing completely with spacing strip template and can not produce the side and move.

As a further improvement of the present technology, the first spring is a compression spring; when the first spring is uncompressed, one end of the limiting strip plate is positioned between two adjacent limiting teeth on the limiting circular disc.

As a further improvement of the technology, the maximum vertical height of the short inclined plane on the limiting block is S1, and the maximum vertical height of the long inclined plane is S2; the depth of the limiting groove on the second fixing block is S3; s2 > S3 > S1. Such design lies in, when the stopper entered into the spacing groove, because the biggest vertical height on the short inclined plane on the stopper is greater than the groove depth of spacing groove on the second fixed block, so the slider can't drive the stopper and remove to the direction of keeping away from the second fixed block, and then the slider also can't remove. The maximum vertical height of the long inclined plane on the limiting block is larger than the groove depth of the limiting groove on the second fixing block, so that when one end of the unlocking plate with a round corner can extrude the long inclined plane on the limiting block, the limiting block moves towards the direction of the limiting block spring under the extrusion of the unlocking plate, and the limiting block spring is compressed; when the short inclined plane of the limiting block also stretches out of the limiting groove, the sliding block can drive the limiting block to move towards the direction far away from the second fixing block, and the limiting block is separated from the limiting groove. The limiting block spring has the effect that the limiting block can move and reset under the reset action of the limiting block spring.

As a further improvement of the present technology, the unlocking plate has a rounded corner at one end of the slide groove. Due to the action of the curved surface of the round angle, the end of the unlocking plate with the round angle can more easily extrude the long inclined plane on the limiting block; in addition, under the high-frequency extrusion, the fillet can also play a role in reducing the abrasion.

As a further improvement of the technology, the limiting block spring is a compression spring; when the limiting block spring is not compressed, one end of the limiting block with the long inclined plane extends out of the limiting block sliding groove.

As a further improvement of the present technology, the first bevel gear, the second bevel gear, the third bevel gear, the fourth bevel gear, the fifth bevel gear, the sixth bevel gear, the seventh bevel gear, and the eighth bevel gear have the same size.

As a further improvement of the present technology, the first direction changing gear and the second direction changing gear have the same size.

The working principle of the first adjusting mechanism and the working principle of the second adjusting mechanism are the same, and for the first adjusting mechanism: the limiting disc is fixed on the fixed rod; spacing strip template, first guide block, first spring and the design of first fixed block lie in: firstly, when the first spring is uncompressed, one end of the limiting strip-shaped plate is positioned between two adjacent limiting teeth on the limiting disc, and the limiting strip-shaped plate is limited, so that the swinging plate cannot swing; secondly, when spacing bar type board when the direction of keeping away from spacing disc removes under the external force pulling, first guide block follows spacing bar type board motion, and first spring is compressed, breaks away from between two adjacent spacing tooth from the one end of spacing bar type board, and spacing bar type board no longer by spacingly, so the user can make the swing plate swing around the axis of dead lever through the handle, and the ring cover is rotatory around the axis of dead lever under the drive of swing plate. The effect of first spring is, under the power that resets of first spring, first guide block drives spacing template and removes and resets, and the one end reinsertion of spacing template is between two adjacent spacing teeth, and spacing template is spacing once more. The limiting block is matched with a limiting groove in the second fixing block, the second fixing block is matched with the accommodating groove, the second fixing block can relatively enter the sliding accommodating groove in the process that the sliding block moves towards the direction of the second fixing block, the second fixing block extrudes the long inclined plane on the limiting block, the limiting block moves towards the direction of the limiting block spring, and the limiting block spring is compressed; along with the continuous removal of slider, when the stopper was located the position of spacing groove, under the restoring force of stopper spring, the stopper inserted the spacing groove fast, and the groove face of holding tank is touched to the second fixed block this moment, and the slider can't continue to move to the second fixed block direction, and the stopper is spacing by the spacing groove, and the slider also can't move to the direction of keeping away from the second fixed block. The sliding block is symmetrically provided with two third guide blocks, so that when the sliding block slides in the sliding groove, the third guide blocks slide in the third guide grooves, and the sliding block can stably slide in the sliding groove; in addition, the third guide block is positioned in the third guide groove, so that the slide block cannot be separated from the sliding groove. The unlocking plate, the second spring and the second guide block are designed in such a way that one end of the unlocking plate, which is provided with a round corner, extrudes the long inclined surface on the limiting block under the action of external force, and then the limiting block can be unlocked and limited; when the unlocking plate moves towards the direction of the limiting block, the second guide block moves along with the unlocking plate, and the second spring is compressed; when the unlocking plate is not acted by external force any more, the second guide block drives the unlocking plate to move and reset under the reset action of the second spring.

A first rack and a second rack in the first stretcher side plate are respectively meshed with the first change gear; and a first rack and a second rack in the second stretcher side plate are respectively meshed with the second change gear. When the sliding block of the first adjusting mechanism in the first stretcher side plate moves in the sliding groove, the first rack in the first stretcher side plate moves along with the sliding block of the first adjusting mechanism in the first stretcher side plate, under the action of the turning of the first turning gear, the moving direction of the second rack in the first stretcher side plate is opposite to that of the first rack in the first stretcher side plate, and further the moving direction of the sliding block of the first adjusting mechanism in the first stretcher side plate is always opposite to that of the sliding block of the second adjusting mechanism in the first stretcher side plate. When the first change gear rotates, the rotating direction and the speed of the second change gear are basically the same with those of the first change gear under the synchronous action of the synchronizing mechanism, so that under the change action of the second change gear, the moving direction of a second rack in the second stretcher side plate is opposite to that of a first rack in the second stretcher side plate, and further, the moving direction of a sliding block of the first adjusting mechanism in the second stretcher side plate is always opposite to that of a sliding block of the second adjusting mechanism in the second stretcher side plate. Finally, when any one of the sliding blocks in the first stretcher side plate or the second stretcher side plate moves, other sliding blocks in the first stretcher side plate or the second stretcher side plate also act correspondingly.

For the synchronization mechanism: when the first change gear or the second change gear firstly rotates, the working principle is the same, taking the first change gear as an example: when the first change gear rotates, the first change gear drives the second change gear to rotate through the first rotating shaft, the first bevel gear, the second rotating shaft, the third bevel gear, the fourth bevel gear, the third rotating shaft, the fifth bevel gear, the sixth bevel gear, the fourth rotating shaft, the seventh bevel gear, the eighth bevel gear and the fifth rotating shaft; the first change gear and the second change gear rotate in the same direction. The first bevel gear, the second bevel gear, the third bevel gear, the fourth bevel gear, the fifth bevel gear, the sixth bevel gear, the seventh bevel gear and the eighth bevel gear are the same in size, and the first change gear and the second change gear are the same in size; therefore, after the first change gear rotates and a series of transmission is carried out, the rotating speed of the second change gear and the rotating speed of the first change gear are basically unchanged. Finally, the synchronization mechanism functions as: after the first change gear rotates, the rotating direction and the rotating speed of the second change gear are kept unchanged from those of the first change gear, so that the first change gear and the second change gear realize a synchronous effect.

When the stretcher of the invention conveys patients on a flat road surface, the limiting block of the first adjusting mechanism in the first stretcher side plate does not generate limiting action with the second fixing block in the first adjusting mechanism, and the limiting block of the second adjusting mechanism in the first stretcher side plate does not generate limiting action with the second fixing block in the second adjusting mechanism; the limiting block of the first adjusting mechanism in the second stretcher side plate does not produce limiting action with the second fixing block in the first adjusting mechanism, and the limiting block of the second adjusting mechanism in the second stretcher side plate does not produce limiting action with the second fixing block in the second adjusting mechanism. When the stretcher of the invention conveys patients on a flat road surface, the swinging plates in all the first adjusting mechanisms are in horizontal positions, one end of the limiting strip-shaped plate is positioned between two adjacent limiting teeth of the limiting disc, and the state of the swinging plates is limited; and the swinging plates in all the second adjusting mechanisms are in horizontal positions, one end of the limiting strip plate is positioned between two adjacent limiting teeth of the limiting disc, and the states of the swinging plates are limited. The user can lift the stretcher by the handle, and all the stretchers can stably convey patients in a horizontal mode because all the swinging plates are in the horizontal position. The user can be through adjusting the distance of two sliders in first stretcher curb plate or the second stretcher curb plate for the distance between the handle also can be adjusted relatively, and the person of facilitating the use exerts oneself better and lifts the stretcher.

When the stretcher of the invention transports patients between stairs, users cooperatively pull the limiting strip-shaped plates in all the first adjusting mechanisms and the second adjusting mechanisms to move towards the direction far away from the limiting disc, the first guide block moves along the limiting strip-shaped plates, the first spring is compressed, one end of each limiting strip-shaped plate is separated from the space between two adjacent limiting teeth, the limiting strip-shaped plates are not limited any more, and then the users can enable the swinging plates to swing around the axis of the fixed rod through the handles, and the ring sleeve rotates around the axis of the fixed rod under the driving of the swinging plates. A user positioned on the upper side of the stair swings the swinging plates in the first adjusting mechanism and the second adjusting mechanism to be in a vertical state through the handle, and the handle is positioned on the upper side of the stretcher cloth; the user who is located the stair downside swings the pendulum plate in the first adjustment mechanism and the second adjustment mechanism of this department to vertical state through the handle, and the handle is located the downside of stretcher cloth. Subsequently, the user cooperates the spacing template of release, so under the power that resets of first spring, first guide block drives spacing template removal and resets, and the one end reinsertion of spacing template is spacing between two adjacent spacing teeth, and spacing template is spacing once more. When all the limiting strip plates are limited, the states of all the swinging plates are locked; therefore, the stretcher is prevented from being inclined due to the swinging of the swinging plate when the stretcher is lifted, so that a patient can slide down from the stretcher to cause secondary injury.

Finally, wherein the user pulls the handle to make the limiting groove of stopper and second fixed block produce limiting displacement in the slider to first adjustment mechanism in the first stretcher curb plate is the example: a user pulls the handle to move towards the direction of the second fixed block, and the handle drives the sliding block to move towards the direction of the second fixed block through the swinging plate, the ring sleeve and the fixed rod; when the sliding block moves towards the direction of the second fixed block, the second fixed block relatively enters the sliding accommodating groove, the second fixed block extrudes the long inclined plane on the limiting block, the limiting block moves towards the direction of the limiting block spring, and the limiting block spring is compressed; along with the continuous removal of slider, when the stopper was located the position of spacing groove, under the restoring force of stopper spring, the stopper inserted the spacing groove fast, and the groove face of holding tank is touched to the second fixed block this moment, and the slider can't continue to move to the second fixed block direction, and the stopper is spacing by the spacing groove, and the slider also can't move to the direction of keeping away from the second fixed block. For the first stretcher side plate, the sliding block in the first adjusting mechanism drives the first rack to move, so that under the action of the turning of the first turning gear, the moving direction of the second rack in the first stretcher side plate is opposite to that of the first rack in the first stretcher side plate, the moving direction of the sliding block of the first adjusting mechanism in the first stretcher side plate is always opposite to that of the sliding block of the second adjusting mechanism in the first stretcher side plate, and the sliding block in the second adjusting mechanism is finally positioned in a limited state. Due to the synchronous action of the synchronizing mechanism, after the first change gear rotates, the rotating direction and the rotating speed of the second change gear are kept unchanged with the rotating direction and the rotating speed of the first change gear, so that under the change action of the second change gear, the moving direction of a second rack in the second stretcher side plate is opposite to that of a first rack in the second stretcher side plate, the moving direction of a sliding block of the first adjusting mechanism in the second stretcher side plate is always opposite to that of a sliding block of the second adjusting mechanism in the second stretcher side plate, and finally, the first adjusting mechanism in the second stretcher side plate and the sliding block in the second adjusting mechanism are both in a limited state. The stretcher has the advantages that all the slide blocks are limited: because the slider is spacing, so the slider can not slide in the sliding tray, and then the user is when lifting the stretcher with the handle, and the handle can not produce lateral shifting, has guaranteed that the stretcher can be smoothly lifted better and can not produce the slope in the transportation process, has protected the patient more. In addition, due to the design of the synchronous mechanism, when any one sliding block actively slides, other sliding blocks can passively follow the sliding block to move, and after the sliding is actively limited, other sliding blocks can also be limited, so that the cooperative fit among users is reduced, and the convenience in use of the stretcher is increased. When the stretcher is conveyed between the stairs, the stretcher can realize that the four swinging plates are all in a vertical state, the two handles at one side of the stretcher are positioned at the upper side of the stretcher, and the two handles at the other side of the stretcher are positioned at the lower side of the stretcher, so that the stretcher can adapt to the fluctuation of the height in the conveying process between the stairs, the cloth of the stretcher is in a horizontal state as much as possible, and the secondary injury caused by the fact that a patient slides down from the stretcher is prevented.

When the stretcher of the invention is not used for transporting patients between stairs, users press the pressing plates at two sides in a cooperative manner, the unlocking plates connected with the pressing plates are extruded, the working procedures of all the unlocking plates are the same, and the unlocking plate of the first adjusting mechanism in the first stretcher side plate is taken as an example: the unlocking plate enables one end of the unlocking plate with a round corner to extrude the long inclined plane on the limiting block under the action of external force, when the unlocking plate moves towards the direction of the limiting block, the second guide block moves along with the unlocking plate, and the second spring is compressed; the limiting block moves towards the limiting block spring direction under the extrusion of the unlocking plate, and the limiting block spring is compressed; when the short inclined plane of stopper also stretched out the spacing groove, the slider just can drive the stopper and remove to the direction of keeping away from the second fixed block, and the stopper breaks away from the spacing groove, and finally the slider no longer is spacing. After the second fixed block breaks away from the holding tank of slider, under the effect that resets of stopper spring, the stopper can remove and reset. When the unlocking plate is not acted by external force any more, the second guide block drives the unlocking plate to move and reset under the reset action of the second spring. Finally, after all the sliding blocks are separated from the limit, users can adjust the swinging plate to be in a horizontal state again. The design of the two pressing plates in the stretcher has the advantages that users are prevented from sequentially pressing the unlocking plates to unlock and limit the sliding blocks, and the convenience in use of the stretcher is increased.

Compared with the traditional stretcher technology, the swinging plates in the first adjusting mechanism and the second adjusting mechanism can be adjusted to adapt to different conditions: first, when the stretcher transported the patient on the horizontal road, the balance weight was in the horizontality, and the user can be through adjusting the distance of two sliders in first stretcher curb plate or the second stretcher curb plate for the distance between the handle also can be adjusted relatively, and the person of facilitating the use exerts oneself better and lifts the stretcher. Secondly, when the stretcher transports a patient between the stairs, the four swing plates can be in a vertical state through adjustment, the two handles on one side of the stretcher are positioned on the upper side of the stretcher, and the two handles on the other side of the stretcher are positioned on the lower side of the stretcher, so that the stretcher can adapt to the fluctuation in the transportation process between the stairs, the cloth of the stretcher is in a horizontal state as much as possible, and the patient is prevented from sliding down from the stretcher to cause secondary injury. In addition, due to the design of the synchronizing mechanism and the two pressing plates, the cooperative fit among users is reduced, and the convenience in use of the stretcher is improved. The invention has simple structure and better use effect.

Drawings

Fig. 1 is an overall schematic view of the stretcher.

Fig. 2 is a connection schematic diagram of the whole bottom elevation of the stretcher.

Fig. 3 is a schematic view of a stretcher cloth installation.

Fig. 4 is a schematic sectional view of the installation of the first and second adjustment mechanisms.

Fig. 5 is a schematic front view of the first rack and the second rack respectively engaged with the first change gear.

Fig. 6 is a schematic sectional front view of the slider mounting.

Fig. 7 is a schematic structural view of the first adjustment mechanism.

FIG. 8 is a schematic cross-sectional view of a slider.

Fig. 9 is a schematic structural diagram of a limiting block.

Fig. 10 is a schematic view of the unlocking plate structure.

Fig. 11 is a schematic view of the handle mounting.

Fig. 12 is a schematic sectional front view of the first guide block.

Fig. 13 is a sectional view of the first fixing block.

Fig. 14 is a schematic view of the first guide block installation.

Fig. 15 is a schematic view of a first stretcher side panel configuration.

Fig. 16 is a schematic cross-sectional view of a first stretcher side panel.

Fig. 17 is an enlarged (first) view of a first stretcher side panel in section.

Fig. 18 is a partially enlarged (second) cross-sectional view of the first stretcher side plate.

Fig. 19 is a schematic view of a synchronization mechanism.

FIG. 20 is a schematic view of the platen installation.

Number designation in the figures: 1. fixing a stretcher plate; 2. a stretcher cloth; 3. a first stretcher side panel; 4. a second stretcher side panel; 5. a first adjustment mechanism; 6. a second adjustment mechanism; 7. a sliding groove; 8. a third guide groove; 9. a slider; 10. a third guide block; 12. a second fixed block; 13. a limiting block; 14. a stopper spring; 15. a limiting block chute; 16. an unlocking plate; 17. a second guide block; 18. a second spring; 19. a second guide groove; 20. a limiting groove; 21. sleeving a ring; 22. a limiting disc; 23. a limiting strip plate; 24. a first fixed block; 25. a handle; 26. a swinging plate; 27. fixing the rod; 28. accommodating grooves; 29. a short bevel; 30. a long inclined plane; 31. round corners; 32. limiting teeth; 33. a first guide block; 34. a first spring; 35. a first guide groove; 36. a sliding through groove; 37. an unlocking plate chute; 40. a synchronization mechanism; 41. a first change gear; 42. a first rotating shaft; 43. a first bevel gear; 44. a second bevel gear; 45. a second rotating shaft; 46. a third fixed block; 47. a third bevel gear; 48. a fourth bevel gear; 49. a third rotating shaft; 50. a fourth fixed block; 51. a fifth bevel gear; 52. a sixth bevel gear; 54. a fifth fixed block; 55. a fourth rotating shaft; 56. a seventh bevel gear; 57. an eighth bevel gear; 58. a fifth rotating shaft; 59. a second change gear; 60. pressing a plate; 61. a first rack; 62. a second rack; 63. a first support block; 64. a second support block; 65. a rack chute; 66. a shaft hole; 67. and a rack guide hole.

Detailed Description

As shown in fig. 1 and 2, the stretcher comprises a stretcher fixing plate 1, a stretcher cloth 2, a first stretcher side plate 3, a second stretcher side plate 4, a first adjusting mechanism 5, a second adjusting mechanism 6, a sliding groove 7, a third guide groove 8, an unlocking plate sliding groove 37, a second guide groove 19, a pressing plate 60, a first rack 61, a second rack 62, a first supporting block 63, a second supporting block 64, a rack sliding groove 65, a shaft hole 66, a rack guide hole 67 and a synchronizing mechanism 40; as shown in fig. 3, a stretcher cloth 2 is arranged between two stretcher fixing plates 1; as shown in fig. 1, a first stretcher side plate 3 and a second stretcher side plate 4 are respectively installed at both ends of the stretcher fixing plate 1.

The structure and the mounted structure of the first stretcher side plate 3 and the second stretcher side plate 4 are the same, to the first stretcher side plate 3: as shown in fig. 15 and 16, the first stretcher side plate 3 is symmetrically provided with two sliding grooves 7 on the side far away from the stretcher cloth 2; two third guide grooves 8 are symmetrically formed in two sides of each sliding groove 7; as shown in fig. 18, two unlocking plate sliding grooves 37 are symmetrically formed on both end surfaces of the first stretcher side plate 3; each unlocking plate slide slot 37 communicates with a corresponding slide slot 7; a second guide groove 19 is formed on the side surface of each unlocking plate sliding groove 37; as shown in fig. 4, the first adjustment mechanism 5 and the second adjustment mechanism 6 are respectively installed in the two slide grooves 7; as shown in fig. 16, the first stretcher side plate 3 is provided with a rack sliding groove 65 at the middle part; a shaft hole 66 is formed in the middle of the side surface of the rack sliding groove 65; the rack sliding groove 65 is respectively communicated with the two sliding grooves 7; a first supporting block 63 is arranged on the top groove surface of the sliding groove 7 provided with the first adjusting mechanism 5; a second supporting block 64 is arranged on the bottom groove surface of the sliding groove 7 provided with the second adjusting mechanism 6; the first supporting block 63 and the second supporting block 64 are both close to the rack sliding groove 65; as shown in fig. 17, the first support block 63 and the second support block 64 are both provided with a through rack guide hole 67 therein; as shown in fig. 4, one end of the first rack 61 is mounted on the first adjustment mechanism 5, and the other end passes through the rack guide hole 67 of the first support block 63 and enters the rack chute 65; one end of the second rack 62 is mounted on the second adjusting mechanism 6, and the other end passes through the rack guide hole 67 of the second support block 64 and enters the rack slide groove 65.

As shown in fig. 1, the first adjustment mechanism 5 in the first stretcher side plate 3 and the first adjustment mechanism 5 in the second stretcher side plate 4 are opposed; the second adjustment mechanism 6 in the first stretcher side plate 3 is opposite to the second adjustment mechanism 6 in the second stretcher side plate 4; the first adjustment mechanism 5 and the second adjustment mechanism 6 are identical.

As shown in fig. 2, for two platens 60: one end of a press plate 60 is connected to the first adjustment mechanism 5 in the first stretcher side plate 3 and the other end is connected to the first adjustment mechanism 5 in the second stretcher side plate 4; the other presser plate 60 is connected at one end to the second adjustment mechanism 6 in the first stretcher side plate 3 and at the other end to the second adjustment mechanism 6 in the second stretcher side plate 4.

As shown in fig. 2, two stretcher securing plates 1 are located between two pressure plates 60.

As shown in fig. 6, 7 and 8, the first adjusting mechanism 5 includes a sliding block 9, a third guide block 10, a second fixing block 12, a limiting block 13, a limiting block spring 14, a limiting block sliding slot 15, an unlocking plate 16, a second guide block 17, a second spring 18, a limiting slot 20, a ring sleeve 21, a limiting disc 22, a limiting strip-shaped plate 23, a first fixing block 24, a handle 25, a swinging plate 26, a fixing rod 27, a receiving slot 28, a short inclined plane 29, a long inclined plane 30, a round corner 31, a limiting tooth 32, a first guide block 33, a first spring 34, a first guide slot 35 and a sliding through slot 36, as shown in fig. 6, wherein the sliding block 9 is installed in the corresponding sliding slot 7 in a sliding fit manner; as shown in fig. 6 and 8, two third guide blocks 10 are symmetrically mounted on two sides of the sliding block 9; the two third guide blocks 10 are respectively installed in the two third guide grooves 8 in a sliding fit manner; as shown in fig. 8 and 11, one end of the fixing rod 27 is mounted on the sliding block 9, and the other end is mounted with the limiting disc 22; the fixing rod 27 is perpendicular to the first stretcher side plate 3; as shown in fig. 12, a plurality of limiting teeth 32 are uniformly distributed on the outer circumferential surface of the limiting disc 22 along the circumferential direction; as shown in fig. 7 and 11, the ring sleeve 21 is nested on the fixing rod 27, and the ring sleeve 21 is positioned between the sliding block 9 and the limiting disk 22; one end of the swing plate 26 is mounted on the outer circular surface of the ring sleeve 21; the handle 25 and the first fixing block 24 are both arranged on the side surface of the swinging plate 26 far away from the sliding block 9; the handle 25 is positioned at one end of the swinging plate 26 far away from the ring sleeve 21, and the first fixed block 24 is positioned between the limiting disc 22 and the handle 25; as shown in fig. 13, a through sliding through groove 36 is opened in the first fixing block 24; two first guide grooves 35 are symmetrically formed on two sides of the sliding through groove 36; as shown in fig. 12 and 14, the limiting strip-shaped plate 23 is installed in the sliding through groove 36 in a sliding fit manner, and both ends of the limiting strip-shaped plate 23 extend out of the sliding through groove 36; two first guide blocks 33 are symmetrically arranged on two sides of the limiting strip plate 23; the two first guide blocks 33 are respectively positioned in the two first guide grooves 35; the first guide block 33 slides in the first guide groove 35; one ends of the two first springs 34 are respectively installed on the two first guide blocks 33, and the other ends are respectively installed on the groove surfaces of the two first guide grooves 35; the two first springs 34 are respectively positioned in the two first guide grooves 35; one end of the limiting strip plate 23 is matched with the limiting teeth 32 on the limiting disc 22.

As shown in fig. 8, the side surface of the slider 9 is provided with a receiving groove 28; the top groove surface of the accommodating groove 28 is provided with a limiting block sliding groove 15; as shown in fig. 6 and 9, the limiting block 13 is slidably mounted in the limiting block sliding groove 15; one end of a limiting block spring 14 is arranged on the limiting block 13, and the other end of the limiting block spring is arranged on the groove surface of the limiting block sliding groove 15; one end of the limiting block 13, which is far away from the limiting block spring 14, is provided with a short inclined surface 29 and a long inclined surface 30; as shown in fig. 6, a second fixing block 12 is mounted on the side groove surface of the sliding groove 7 having the unlocking plate sliding groove 37; as shown in fig. 11, a limiting groove 20 is formed on the upper plate surface of the second fixing block 12; as shown in fig. 6 and 10, the unlocking plate 16 is mounted in the unlocking plate slide groove 37 in a sliding fit manner, and both ends of the unlocking plate 16 extend out of the unlocking plate slide groove 37; the second guide block 17 is mounted on the unlocking plate 16; the second guide block 17 is positioned in the second guide groove 19; the second guide block 17 slides in the second guide groove 19; one end of a second spring 18 is arranged on the second guide block 17, and the other end is arranged on the groove surface of the second guide groove 19; the second spring 18 is located in the second guide groove 19.

As shown in fig. 6, for the first adjustment structure: the limiting block 13 is matched with a limiting groove 20 on the second fixing block 12; the second fixing block 12 is matched with the accommodating groove 28; one end of the unlocking plate 16 is matched with the long inclined surface 30 on the limiting block 13.

As shown in fig. 4, for the first adjustment mechanism 5, the second adjustment mechanism 6, the first rack 61 and the second rack 62 in the first stretcher side plate 3: one end of the first rack 61 is mounted on the slider 9 of the first adjusting mechanism 5, and the other end passes through the rack guide hole 67 of the first support block 63 and enters the rack sliding groove 65; one end of the second rack 62 is mounted on the slider 9 of the second adjusting mechanism 6, and the other end passes through the rack guide hole 67 of the second support block 64 and enters the rack slide groove 65.

For the first adjustment mechanism 5, the second adjustment mechanism 6, the first rack 61 and the second rack 62 in the second stretcher side plate 4: one end of the first rack 61 is mounted on the slider 9 of the first adjusting mechanism 5, and the other end passes through the rack guide hole 67 of the first support block 63 and enters the rack sliding groove 65; one end of the second rack 62 is mounted on the slider 9 of the second adjusting mechanism 6, and the other end passes through the rack guide hole 67 of the second support block 64 and enters the rack slide groove 65.

As shown in fig. 2 and 20, the two pressing plates 60: one end of a pressing plate 60 is connected with the unlocking plate 16 of the first adjusting mechanism 5 in the first stretcher side plate 3, and the other end is connected with the unlocking plate 16 of the first adjusting mechanism 5 in the second stretcher side plate 4; the other presser plate 60 is connected at one end to the unlocking plate 16 of the second adjustment mechanism 6 in the first stretcher side plate 3 and at the other end to the unlocking plate 16 of the second adjustment mechanism 6 in the second stretcher side plate 4.

As shown in fig. 1, the synchronizing mechanism 40 is mounted on the first stretcher side plate 3, the stretcher fixing plate 1 and the second stretcher side plate 4; the first rack 61 and the second rack 62 in the first stretcher side plate 3 are both fitted with the synchronizing mechanism 40; the first and

second racks

61, 62 in the second stretcher side panel 4 are both engaged with the synchronizing mechanism 40.

As shown in fig. 19, the above-mentioned synchronizing mechanism 40 includes a first direction-changing gear 41, a first rotating shaft 42, a first bevel gear 43, a second bevel gear 44, a second rotating shaft 45, a third fixing block 46, a third bevel gear 47, a fourth bevel gear 48, a third rotating shaft 49, a fourth fixing block 50, a fifth bevel gear 51, a sixth bevel gear 52, a fifth fixing block 54, a seventh bevel gear 56, an eighth bevel gear 57, a fourth rotating shaft 55, a fifth rotating shaft 58, and a second direction-changing gear 59, as shown in fig. 2, 4, and 17, wherein the first rotating shaft 42 is mounted in a shaft hole 66 at a rack sliding slot 65 of the first stretcher side plate 3 through a bearing, and both ends of the first rotating shaft 42 extend out of the shaft hole 66; one end of the first rotating shaft 42 is provided with a first change gear 41, and the other end is provided with a first bevel gear 43; the first change gear 41 is positioned in the rack sliding slot 65 of the first stretcher side plate 3; as shown in fig. 2 and 19, the third fixing block 46 is mounted on the first stretcher side plate 3; the third fixing block 46 has a through circular hole; the second rotating shaft 45 is installed in a round hole of the third fixing block 46 through a bearing, and two ends of the second rotating shaft 45 penetrate through the third fixing block 46; one end of the second rotating shaft 45 is provided with a second bevel gear 44, and the other end is provided with a third bevel gear 47; the first bevel gear 43 and the second bevel gear 44 are meshed; the fourth fixing blocks 50 are mounted on the corresponding stretcher fixing plates 1; the fourth fixing block 50 has a through circular hole; the third rotating shaft 49 is mounted in a round hole of the fourth fixing block 50 through a bearing, and two ends of the third rotating shaft 49 penetrate through the fourth fixing block 50; one end of the third rotating shaft 49 is provided with a fourth bevel gear 48, and the other end is provided with a fifth bevel gear 51; the third bevel gear 47 and the fourth bevel gear 48 are meshed; the fifth fixing block 54 is mounted on the second stretcher side plate 4; the fifth fixing block 54 has a through round hole; the fourth rotating shaft 55 is mounted in a circular hole of the fifth fixing block 54 through a bearing, and two ends of the fourth rotating shaft 55 penetrate through the fifth fixing block 54; a sixth bevel gear 52 is mounted at one end of the fourth rotating shaft 55, and a seventh bevel gear 56 is mounted at the other end; the fifth bevel gear 51 is meshed with the sixth bevel gear 52; the fifth rotating shaft 58 is mounted in a shaft hole 66 at the rack sliding groove 65 of the second stretcher side plate 4 through a bearing, and two ends of the fifth rotating shaft 58 extend out of the shaft hole 66; one end of the fifth rotating shaft 58 is provided with a second change gear 59, and the other end is provided with an eighth bevel gear 57; the second change gear 59 is positioned in the rack sliding groove 65 of the first stretcher side plate 3; the seventh bevel gear 56 meshes with the eighth bevel gear 57.

As shown in fig. 5, the first rack 61 and the second rack 62 of the first stretcher side plate 3 are respectively engaged with the first direction changing gear 41; the first rack 61 and the second rack 62 in the second stretcher side plate 4 are respectively engaged with the second change gear 59.

As shown in fig. 12, the side surfaces of the stopper teeth 32 are parallel to the side surfaces of the adjacent stopper teeth 32. Such design lies in that, when the one end of spacing strip template 23 was located between two adjacent spacing tooth 32, the both sides of spacing strip template 23 and the side of two spacing tooth 32 laminate completely, and two spacing tooth 32 can be with spacing strip template 23 complete spacing and can not produce the side and move.

As shown in fig. 12, the first spring 34 is a compression spring; when the first spring 34 is uncompressed, one end of the limiting strip plate 23 is positioned between two adjacent limiting teeth 32 on the limiting disk 22.

The maximum vertical height of the short inclined plane 29 on the limiting block 13 is S1, and the maximum vertical height of the long inclined plane 30 is S2; the depth of the limiting groove 20 on the second fixing block 12 is S3; s2 > S3 > S1. Such design lies in, when stopper 13 entered into spacing groove 20, because the biggest vertical height of the last short inclined plane 29 of stopper 13 is greater than the groove depth of spacing groove 20 on second fixed block 12, so slider 9 can't drive stopper 13 and remove to the direction of keeping away from second fixed block 12, and then slider 9 also can't remove. The maximum vertical height of the long inclined surface 30 on the limiting block 13 is greater than the depth of the limiting groove 20 on the second fixing block 12, so that when one end of the unlocking plate 16 with the round angle 31 can extrude the long inclined surface 30 on the limiting block 13, the limiting block 13 moves towards the limiting block spring 14 under the extrusion of the unlocking plate 16, and the limiting block spring 14 is compressed; when the short inclined surface 29 of the limiting block 13 also extends out of the limiting groove 20, the sliding block 9 can drive the limiting block 13 to move in the direction away from the second fixing block 12, and the limiting block 13 is separated from the limiting groove 20. The stopper spring 14 is used for moving and resetting the stopper 13 under the resetting action of the stopper spring 14.

As shown in fig. 6 and 10, the unlocking plate 16 has a rounded corner 31 at one end of the slide groove 7. Due to the curved surface effect of the round corner 31, the end of the unlocking plate 16 with the round corner 31 can more easily press the long inclined surface 30 on the limiting block 13; in addition, the fillet 31 can also function to reduce wear at high frequency of extrusion.

As shown in fig. 6, the stopper spring 14 is a compression spring; when the stopper spring 14 is uncompressed, the end of the stopper 13 having the long inclined surface 30 extends out of the stopper slide groove 15.

As shown in fig. 19, the first bevel gear 43, the second bevel gear 44, the third bevel gear 47, the fourth bevel gear 48, the fifth bevel gear 51, the sixth bevel gear 52, the seventh bevel gear 56, and the eighth bevel gear 57 have the same size.

As shown in fig. 19, the first direction change gear 41 and the second direction change gear 59 have the same size.

The first adjusting mechanism 5 and the second adjusting mechanism 6 have the same working principle, and for the first adjusting mechanism 5: the limiting disc 22 is fixed on the fixing rod 27; the design of spacing strip template 23, first guide block 33, first spring 34 and first fixed block 24 lies in: firstly, when the first spring 34 is uncompressed, one end of the limiting strip plate 23 is positioned between two adjacent limiting teeth 32 on the limiting disc 22, and the limiting strip plate 23 is limited, so that the swinging plate 26 cannot swing; secondly, when the limiting strip-shaped plate 23 is pulled by external force to move in a direction away from the limiting disc 22, the first guide block 33 moves along with the limiting strip-shaped plate 23, the first spring 34 is compressed, one end of the limiting strip-shaped plate 23 is separated from between two adjacent limiting teeth 32, the limiting strip-shaped plate 23 is no longer limited, then a user can enable the swinging plate 26 to swing around the axis of the fixed rod 27 through the handle 25, and the ring sleeve 21 rotates around the axis of the fixed rod 27 under the driving of the swinging plate 26. The first spring 34 has the function that under the reset force of the first spring 34, the first guide block 33 drives the limiting strip plate 23 to move and reset, one end of the limiting strip plate 23 is inserted between two adjacent limiting teeth 32 again, and the limiting strip plate 23 is limited again. The limiting block 13 is matched with the limiting groove 20 on the second fixing block 12, the second fixing block 12 is matched with the accommodating groove 28, and the effect that when the sliding block 9 moves towards the direction of the second fixing block 12, the second fixing block 12 can relatively enter the sliding accommodating groove 28, the second fixing block 12 extrudes the long inclined plane 30 on the limiting block 13, the limiting block 13 moves towards the limiting block spring 14, and the limiting block spring 14 is compressed; along with the continuous removal of slider 9, when stopper 13 is located the position of spacing groove 20, under stopper spring 14's restoring force, stopper 13 inserts fast in spacing groove 20, and second fixed block 12 touches the groove surface of holding tank 28 this moment, and slider 9 can't continue to move in the direction of second fixed block 12 normal direction, and stopper 13 is spacing by spacing groove 20, and slider 9 also can't move to the direction of keeping away from second fixed block 12. Two third guide blocks 10 are symmetrically arranged on the sliding block 9, so that when the sliding block 9 slides in the sliding groove 7, the third guide blocks 10 slide the sliding block 9 in the third guide grooves 8, and the third guide blocks 10 can enable the sliding block 9 to stably slide in the sliding groove 7; in addition, since the third guide block 10 is located in the third guide groove 8, the slider 9 does not come off from the slide groove 7. The unlocking plate 16, the second spring 18 and the second guide block 17 are designed in such a way that one end of the unlocking plate 16, which is provided with a round angle 31, is extruded on the long inclined surface 30 on the limiting block 13 under the action of external force, and then the limiting block 13 can be unlocked and limited; when the unlocking plate 16 moves towards the direction of the limiting block 13, the second guide block 17 moves along with the unlocking plate 16, and the second spring 18 is compressed; when the unlocking plate 16 is no longer acted by external force, the second guide block 17 drives the unlocking plate 16 to move and reset under the reset action of the second spring 18.

The first rack 61 and the second rack 62 in the first stretcher side plate 3 are respectively engaged with the first change gear 41; the first rack 61 and the second rack 62 in the second stretcher side plate 4 are respectively engaged with the second change gear 59. Then when the sliding block 9 of the first adjusting mechanism 5 in the first stretcher side plate 3 moves in the sliding groove 7, the first rack 61 in the first stretcher side plate 3 follows the sliding block 9 of the first adjusting mechanism 5 in the first stretcher side plate 3, and under the action of the direction change of the first direction change gear 41, the second rack 62 in the first stretcher side plate 3 moves in the direction opposite to the direction of movement of the first rack 61 in the first stretcher side plate 3, and therefore the direction of movement of the sliding block 9 of the first adjusting mechanism 5 in the first stretcher side plate 3 is always opposite to the direction of movement of the sliding block 9 of the second adjusting mechanism 6 in the first stretcher side plate 3. When the first change gear 41 rotates, the rotation direction and speed of the second change gear 59 and the first change gear 41 are substantially the same by utilizing the synchronization function of the synchronization mechanism 40, so that under the change of direction of the second change gear 59, the moving direction of the second rack 62 in the second stretcher side plate 4 is opposite to the moving direction of the first rack 61 in the second stretcher side plate 4, and further, the moving direction of the slider 9 of the first adjustment mechanism 5 in the second stretcher side plate 4 is always opposite to the moving direction of the slider 9 of the second adjustment mechanism 6 in the second stretcher side plate 4. Finally, when any one of the slide blocks 9 of the first stretcher side plate 3 or the second stretcher side plate 4 moves, the other slide block 9 of the first stretcher side plate 3 or the second stretcher side plate 4 also acts accordingly.

For the synchronization mechanism 40: the operating principle when the first direction change gear 41 or the second direction change gear 59 first rotates is the same, taking the first direction change gear 41 as an example: when the first direction changing gear 41 rotates, the first direction changing gear 41 drives the second direction changing gear 59 to rotate through the first rotating shaft 42, the first bevel gear 43, the second bevel gear 44, the second rotating shaft 45, the third bevel gear 47, the fourth bevel gear 48, the third rotating shaft 49, the fifth bevel gear 51, the sixth bevel gear 52, the fourth rotating shaft 55, the seventh bevel gear 56, the eighth bevel gear 57 and the fifth rotating shaft 58; the first direction change gear 41 and the second direction change gear 59 rotate in the same direction. Since the first bevel gear 43, the second bevel gear 44, the third bevel gear 47, the fourth bevel gear 48, the fifth bevel gear 51, the sixth bevel gear 52, the seventh bevel gear 56, and the eighth bevel gear 57 are all the same in size, the first direction changing gear 41 and the second direction changing gear 59 are the same in size; therefore, after the first direction changing gear 41 is rotated, the rotational speed of the second direction changing gear 59 is substantially constant with the rotational speed of the first direction changing gear 41 through a series of transmissions. Finally, the synchronization mechanism 40 functions to: after the first direction changing gear 41 rotates, the rotating direction and the rotating speed of the second direction changing gear 59 are kept unchanged from the rotating direction and the rotating speed of the first direction changing gear 41, so that the first direction changing gear 41 and the second direction changing gear 59 achieve a synchronous effect.

The specific implementation mode is as follows: when the stretcher of the invention carries a patient on a flat road surface, the limiting block 13 of the first adjusting mechanism 5 in the first stretcher side plate 3 does not generate a limiting effect with the second fixing block 12 in the first adjusting mechanism 5, and the limiting block 13 of the second adjusting mechanism 6 in the first stretcher side plate 3 does not generate a limiting effect with the second fixing block 12 in the second adjusting mechanism 6; the limiting block 13 of the first adjusting mechanism 5 in the second stretcher side plate 4 does not produce a limiting effect with the second fixing block 12 in the first adjusting mechanism 5, and the limiting block 13 of the second adjusting mechanism 6 in the second stretcher side plate 4 does not produce a limiting effect with the second fixing block 12 in the second adjusting mechanism 6. When the stretcher of the invention transports patients on a flat road, the swinging plates 26 in all the first adjusting mechanisms 5 are in a horizontal position, one end of the limiting strip-shaped plate 23 is positioned between two adjacent limiting teeth 32 of the limiting disc 22, and the state of the swinging plates 26 is limited; all the swing plates 26 in the second adjusting mechanism 6 are in a horizontal position, one end of the limiting strip plate 23 is positioned between two adjacent limiting teeth 32 of the limiting disc 22, and the state of the swing plates 26 is limited. The user can lift the stretcher by the handle 25, and all the stretchers can smoothly carry the patient in a horizontal manner since all the swing plates 26 are in the horizontal position. The user can be through adjusting the distance of two sliders 9 in first stretcher curb plate 3 or the second stretcher curb plate 4 for the distance between handle 25 also can be adjusted relatively, and the person of facilitating the use exerts oneself better and lifts the stretcher.

When the stretcher of the invention transports patients between stairs, users cooperatively pull the limiting strip-shaped plates 23 in all the first adjusting mechanism 5 and the second adjusting mechanism 6 to move away from the limiting disc 22, the first guide block 33 moves along with the limiting strip-shaped plates 23, the first spring 34 is compressed, one end of each limiting strip-shaped plate 23 is separated from between two adjacent limiting teeth 32, the limiting strip-shaped plates 23 are not limited any more, then the users can enable the swinging plates 26 to swing around the axis of the fixed rod 27 through the handles 25, and the ring sleeves 21 rotate around the axis of the fixed rod 27 under the driving of the swinging plates 26. A user positioned at the upper side of the stairs swings the swinging plates 26 in the first adjusting mechanism 5 and the second adjusting mechanism 6 to be vertical through the handle 25, and the handle 25 is positioned at the upper side of the stretcher cloth 2; the user who is located at the lower side of the staircase swings the swing plates 26 of the first and

second adjusting mechanisms

5 and 6 thereto to the vertical state by the handle 25, and the handle 25 is located at the lower side of the stretcher cloth 2. Subsequently, the users cooperate to release the limiting strip plate 23, so that under the restoring force of the first spring 34, the first guide block 33 drives the limiting strip plate 23 to move and restore, one end of the limiting strip plate 23 is inserted between two adjacent limiting teeth 32 again, and the limiting strip plate 23 is limited again. When all the limiting strip plates 23 are limited, the states of all the swinging plates 26 are locked; thus, the situation that when the stretcher is lifted, the swinging plate 26 swings to cause the stretcher to incline, so that a patient slides down from the stretcher to cause secondary injury is prevented.

Finally, wherein the user pulls the handle 25 to make the limiting block 13 in the sliding block 9 and the limiting groove 20 of the second fixing block 12 generate a limiting effect, taking the first adjusting mechanism 5 in the first stretcher side plate 3 as an example: a user pulls the handle 25 to move towards the direction of the second fixed block 12, and the handle 25 drives the sliding block 9 to move towards the direction of the second fixed block 12 through the swinging plate 26, the ring sleeve 21 and the fixed rod 27; when the sliding block 9 moves towards the direction of the second fixed block 12, the second fixed block 12 relatively enters the sliding accommodating groove 28, the second fixed block 12 presses the long inclined surface 30 on the limiting block 13, the limiting block 13 moves towards the direction of the limiting block spring 14, and the limiting block spring 14 is compressed; along with the continuous removal of slider 9, when stopper 13 is located the position of spacing groove 20, under stopper spring 14's restoring force, stopper 13 inserts fast in spacing groove 20, and second fixed block 12 touches the groove surface of holding tank 28 this moment, and slider 9 can't continue to move in the direction of second fixed block 12 normal direction, and stopper 13 is spacing by spacing groove 20, and slider 9 also can't move to the direction of keeping away from second fixed block 12. For the first stretcher side plate 3, due to the fact that the sliding block 9 in the first adjusting mechanism 5 drives the first rack 61 to move, under the action of the direction change of the first direction change gear 41, the moving direction of the second rack 62 in the first stretcher side plate 3 is opposite to that of the first rack 61 in the first stretcher side plate 3, then the moving direction of the sliding block 9 of the first adjusting mechanism 5 in the first stretcher side plate 3 is always opposite to that of the sliding block 9 of the second adjusting mechanism 6 in the first stretcher side plate 3, and finally the sliding block 9 in the second adjusting mechanism 6 is also in a limited state. Due to the synchronous action of the synchronizing mechanism 40, after the first change gear 41 rotates, the rotating direction and the rotating speed of the second change gear 59 are kept unchanged from the rotating direction and the rotating speed of the first change gear 41, then under the change of direction of the second change gear 59, the moving direction of the second rack 62 in the second stretcher side plate 4 is opposite to the moving direction of the first rack 61 in the second stretcher side plate 4, further, the moving direction of the slider 9 of the first adjusting mechanism 5 in the second stretcher side plate 4 is always opposite to the moving direction of the slider 9 of the second adjusting mechanism 6 in the second stretcher side plate 4, and finally, the slider 9 in the first adjusting mechanism 5 and the second adjusting mechanism 6 in the second stretcher side plate 4 are both in a limited state. The stretcher of the invention has the advantages that all the slide blocks 9 are limited: because the sliding block 9 is limited, the sliding block 9 cannot slide in the sliding groove 7, and then when a user lifts the stretcher by using the handle 25, the handle 25 cannot move transversely, so that the stretcher can be stably lifted without inclination in the conveying process, and a patient is protected more. In addition, due to the design of the synchronizing mechanism 40, when any one sliding block 9 actively slides, other sliding blocks 9 can passively follow the action of the sliding block, and after the sliding is actively limited, other sliding blocks 9 can also be limited, so that the cooperative fit among users is reduced, and the convenience in use of the stretcher is improved. When the stretcher is transported between stairs, the stretcher can realize that the four swinging plates 26 are all in a vertical state, the two handles 25 on one side of the stretcher are positioned on the upper side of the stretcher, and the two handles 25 on the other side of the stretcher are positioned on the lower side of the stretcher, so that the stretcher can adapt to the fluctuation in the transportation process between the stairs, the stretcher cloth 2 is in a horizontal state as much as possible, and the patient is prevented from sliding down from the stretcher to cause secondary injury.

When the stretcher of the present invention is no longer used for transporting patients between stairs, the users press the pressing plates 60 at both sides in a cooperative manner, the unlocking plate 16 connected to the pressing plates 60 is pressed, and the working process of all the unlocking plates 16 is the same, taking the unlocking plate 16 of the first adjusting mechanism 5 in the first stretcher side plate 3 as an example: the unlocking plate 16 enables one end of the unlocking plate 16 with the round corner 31 to press the long inclined surface 30 on the limiting block 13 under the action of external force, when the unlocking plate 16 moves towards the direction of the limiting block 13, the second guide block 17 moves along with the unlocking plate 16, and the second spring 18 is compressed; the limiting block 13 moves towards the limiting block spring 14 under the extrusion of the unlocking plate 16, and the limiting block spring 14 is compressed; when the short inclined surface 29 of the limiting block 13 also extends out of the limiting groove 20, the sliding block 9 can drive the limiting block 13 to move in the direction away from the second fixing block 12, the limiting block 13 is separated from the limiting groove 20, and finally the sliding block 9 is not limited any more. After the second fixing block 12 is separated from the receiving groove 28 of the slider 9, the stopper 13 can move to be reset under the reset action of the stopper spring 14. When the unlocking plate 16 is no longer acted by external force, the second guide block 17 drives the unlocking plate 16 to move and reset under the reset action of the second spring 18. Finally, after all the sliders 9 are disengaged from the limit, the users can adjust the swing plate 26 to the horizontal state again. The design of the two pressing plates 60 in the stretcher of the invention has the advantages that users are prevented from sequentially pressing the unlocking plates 16 to unlock and limit the slide blocks 9, and the convenient use of the stretcher of the invention is increased.

In conclusion, the invention has the main beneficial effects that: the wobble plate 26 in both the first adjustment mechanism 5 and the second adjustment mechanism 6 can be adjusted to accommodate different situations: firstly, when the stretcher transports the patient on the horizontal road, the swing plate 26 is in the horizontal state, and the user can adjust the distance between the two sliding blocks 9 in the first stretcher side plate 3 or the second stretcher side plate 4, so that the distance between the handles 25 can be adjusted relatively, and the user can lift the stretcher better. Secondly, when the stretcher transports a patient between the stairs, the four swing plates 26 can be in a vertical state by adjustment, the two handles 25 on one side of the stretcher are positioned on the upper side of the stretcher, and the two handles 25 on the other side of the stretcher are positioned on the lower side of the stretcher, so that the stretcher can adapt to the fluctuation of the height during the transportation between the stairs, the stretcher cloth 2 is in a horizontal state as much as possible, and the patient is prevented from sliding down from the stretcher to cause secondary injury. In addition, the design of the synchronizing mechanism 40 and the two pressing plates 60 of the present invention reduces the cooperation between the users, increasing the convenience of use of the stretcher of the present invention. The invention has simple structure and better use effect.

Claims

1. The utility model provides a stair stretcher that medical field used which characterized in that: the stretcher comprises a stretcher fixing plate, stretcher cloth, a first stretcher side plate, a second stretcher side plate, a first adjusting mechanism, a second adjusting mechanism, a sliding groove, a third guide groove, an unlocking plate sliding groove, a second guide groove, a pressing plate, a first rack, a second rack, a first supporting block, a second supporting block, a rack sliding groove, a shaft hole, a rack guide hole and a synchronizing mechanism; wherein, a stretcher cloth is arranged between the two stretcher fixing plates; the first stretcher side plate and the second stretcher side plate are respectively arranged at two ends of the stretcher fixing plate;

the structure and the mounting structure of first stretcher curb plate and second stretcher curb plate are the same, to first stretcher curb plate: the side surface of the first stretcher side plate, which is far away from the stretcher cloth, is symmetrically provided with two sliding grooves; two third guide grooves are symmetrically formed in two sides of each sliding groove; two unlocking plate sliding grooves are symmetrically formed in the end faces of the two ends of the first stretcher side plate; each unlocking plate sliding groove is communicated with the corresponding sliding groove; a second guide groove is formed in the side face of each unlocking plate sliding groove; the first adjusting mechanism and the second adjusting mechanism are respectively arranged in the two sliding grooves; the middle part of the first stretcher side plate is provided with a rack sliding groove; the middle position of the side surface of the rack sliding chute is provided with a shaft hole; the rack sliding groove is respectively communicated with the two sliding grooves; a first supporting block is arranged on the top groove surface of the sliding groove provided with the first adjusting mechanism; a second supporting block is arranged on the bottom groove surface of the sliding groove provided with the second adjusting mechanism; the first supporting block and the second supporting block are close to the rack sliding groove; the first supporting block and the second supporting block are both provided with through rack guide holes; one end of the first rack is arranged on the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is arranged on the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove;

the first adjusting mechanism in the first stretcher side plate is opposite to the first adjusting mechanism in the second stretcher side plate; the second adjustment mechanism in the first stretcher side plate is opposite to the second adjustment mechanism in the second stretcher side plate; the first adjusting mechanism and the second adjusting mechanism are the same;

for both platens: one end of a press plate is connected with a first adjusting mechanism in the first stretcher side plate, and the other end of the press plate is connected with a first adjusting mechanism in the second stretcher side plate; one end of the other pressing plate is connected with the second adjusting mechanism in the first stretcher side plate, and the other end of the other pressing plate is connected with the second adjusting mechanism in the second stretcher side plate;

the two stretcher fixing plates are positioned between the two pressing plates;

the first adjusting mechanism comprises a sliding block, a third guide block, a second fixed block, a limiting block spring, a limiting block sliding groove, an unlocking plate, a second guide block, a second spring, a limiting groove, a ring sleeve, a limiting disc, a limiting strip-shaped plate, a first fixed block, a handle, a swinging plate, a fixed rod, a containing groove, a short inclined plane, a long inclined plane, a fillet, a limiting tooth, a first guide block, a first spring, a first guide groove and a sliding through groove, wherein the sliding block is arranged in the corresponding sliding groove in a sliding fit manner; two third guide blocks are symmetrically arranged on two sides of the sliding block; the two third guide blocks are respectively arranged in the two third guide grooves in a sliding fit manner; one end of the fixed rod is arranged on the sliding block, and the other end of the fixed rod is provided with a limiting disc; the fixed rod is vertical to the first stretcher side plate; a plurality of limiting teeth are uniformly distributed on the outer circular surface of the limiting disc along the circumferential direction; the ring sleeve is nested on the fixed rod and is positioned between the sliding block and the limiting disc; one end of the swinging plate is arranged on the outer circular surface of the ring sleeve; the handle and the first fixed block are both arranged on the side surface of the swinging plate far away from the sliding block; the handle is positioned at one end of the swinging plate far away from the ring sleeve, and the first fixed block is positioned between the limiting disc and the handle; a through sliding through groove is formed in the first fixing block; two first guide grooves are symmetrically formed in the two sides of the sliding through groove; the limiting strip-shaped plate is arranged in the sliding through groove in a sliding fit mode, and two ends of the limiting strip-shaped plate extend out of the sliding through groove; two first guide blocks are symmetrically arranged on two sides of the limiting strip-shaped plate; the two first guide blocks are respectively positioned in the two first guide grooves; the first guide block slides in the first guide groove; one ends of the two first springs are respectively arranged on the two first guide blocks, and the other ends of the two first springs are respectively arranged on the groove surfaces of the two first guide grooves; the two first springs are respectively positioned in the two first guide grooves; one end of the limiting strip template is matched with the limiting teeth on the limiting disc;

the side surface of the sliding block is provided with an accommodating groove; a limiting block sliding groove is formed in the top groove surface of the accommodating groove; the limiting block is slidably arranged in the limiting block sliding groove; one end of the limiting block spring is arranged on the limiting block, and the other end of the limiting block spring is arranged on the groove surface of the limiting block sliding groove; one end of the limiting block, which is far away from the limiting block spring, is provided with a short inclined plane and a long inclined plane; a second fixed block is arranged on the side groove surface of the sliding groove with the unlocking plate sliding groove; a limiting groove is formed in the upper plate surface of the second fixing block; the unlocking plate is arranged in the unlocking plate sliding groove in a sliding fit mode, and two ends of the unlocking plate extend out of the unlocking plate sliding groove; the second guide block is arranged on the unlocking plate; the second guide block is positioned in the second guide groove; the second guide block slides in the second guide groove; one end of the second spring is arranged on the second guide block, and the other end of the second spring is arranged on the groove surface of the second guide groove; the second spring is positioned in the second guide groove;

for the first adjustment structure: the limiting block is matched with a limiting groove on the second fixing block; the second fixed block is matched with the accommodating groove; one end of the unlocking plate is matched with the long inclined plane on the limiting block;

to first adjustment mechanism, second adjustment mechanism, first rack and second rack in the first stretcher side plate: one end of the first rack is arranged on the sliding block of the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is arranged on the sliding block of the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove;

to first adjustment mechanism, second adjustment mechanism, first rack and second rack in the second stretcher curb plate: one end of the first rack is arranged on the sliding block of the first adjusting mechanism, and the other end of the first rack penetrates through the rack guide hole of the first supporting block and enters the rack sliding groove; one end of the second rack is arranged on the sliding block of the second adjusting mechanism, and the other end of the second rack penetrates through the rack guide hole of the second supporting block and enters the rack sliding groove;

the two pressing plates are as follows: one end of one pressing plate is connected with an unlocking plate of a first adjusting mechanism in the first stretcher side plate, and the other end of the pressing plate is connected with an unlocking plate of a first adjusting mechanism in the second stretcher side plate; one end of the other pressure plate is connected with an unlocking plate of the second adjusting mechanism in the first stretcher side plate, and the other end of the other pressure plate is connected with an unlocking plate of the second adjusting mechanism in the second stretcher side plate;

the synchronous mechanism is arranged on the first stretcher side plate, the stretcher fixing plate and the second stretcher side plate; a first rack and a second rack in the first stretcher side plate are matched with the synchronous mechanism; the first rack and the second rack in the second stretcher side plate are matched with the synchronous mechanism;

the synchronizing mechanism comprises a first change gear, a first rotating shaft, a first bevel gear, a second rotating shaft, a third fixed block, a third bevel gear, a fourth bevel gear, a third rotating shaft, a fourth fixed block, a fifth bevel gear, a sixth bevel gear, a fifth fixed block, a seventh bevel gear, an eighth bevel gear, a fourth rotating shaft, a fifth rotating shaft and a second change gear, wherein the first rotating shaft is arranged in a shaft hole at a rack sliding groove of the first stretcher side plate through a bearing, and two ends of the first rotating shaft extend out of the shaft hole; one end of the first rotating shaft is provided with a first change gear, and the other end of the first rotating shaft is provided with a first bevel gear; the first change gear is positioned in the rack sliding groove of the first stretcher side plate; the third fixing block is arranged on the first stretcher side plate; the third fixing block is provided with a through round hole; the second rotating shaft is arranged in a round hole of the third fixed block through a bearing, and two ends of the second rotating shaft penetrate through the third fixed block; one end of the second rotating shaft is provided with a second bevel gear, and the other end of the second rotating shaft is provided with a third bevel gear; the first bevel gear is meshed with the second bevel gear; the fourth fixed block is arranged on the corresponding stretcher fixed plate; the fourth fixed block is provided with a through round hole; the third rotating shaft is arranged in a round hole of the fourth fixed block through a bearing, and two ends of the third rotating shaft penetrate through the fourth fixed block; one end of the third rotating shaft is provided with a fourth bevel gear, and the other end of the third rotating shaft is provided with a fifth bevel gear; the third bevel gear is meshed with the fourth bevel gear; the fifth fixing block is arranged on the second stretcher side plate; the fifth fixed block is provided with a through round hole; the fourth rotating shaft is arranged in a round hole of the fifth fixing block through a bearing, and two ends of the fourth rotating shaft penetrate through the fifth fixing block; one end of the fourth rotating shaft is provided with a sixth bevel gear, and the other end of the fourth rotating shaft is provided with a seventh bevel gear; the fifth bevel gear is meshed with the sixth bevel gear; the fifth rotating shaft is arranged in a shaft hole at the rack sliding groove of the second stretcher side plate through a bearing, and two ends of the fifth rotating shaft extend out of the shaft hole; one end of the fifth rotating shaft is provided with a second steering gear, and the other end of the fifth rotating shaft is provided with an eighth bevel gear; the second change gear is positioned in the rack sliding groove of the first stretcher side plate; the seventh bevel gear is meshed with the eighth bevel gear;

a first rack and a second rack in the first stretcher side plate are respectively meshed with a first change gear; a first rack and a second rack in the second stretcher side plate are respectively meshed with the second change gear;

one end of the unlocking plate, which is positioned in the sliding groove, is provided with a round angle;

the side surfaces of the limiting teeth are parallel to the side surfaces of the adjacent limiting teeth;

the first spring is a compression spring; when the first spring is not compressed, one end of the limiting strip plate is positioned between two adjacent limiting teeth on the limiting disc;

the maximum vertical height of the short inclined plane on the limiting block is S1, and the maximum vertical height of the long inclined plane is S2; the depth of the limiting groove on the second fixing block is S3; s2 > S3 > S1.

2. The stair stretcher for medical field according to claim 1, characterized in that: the limiting block spring is a compression spring; when the limiting block spring is not compressed, one end of the limiting block with the long inclined plane extends out of the limiting block sliding groove.

3. The stair stretcher for medical field according to claim 1, characterized in that: the first bevel gear, the second bevel gear, the third bevel gear, the fourth bevel gear, the fifth bevel gear, the sixth bevel gear, the seventh bevel gear and the eighth bevel gear are all the same in size.

4. The stair stretcher for medical field according to claim 1, characterized in that: the first change gear and the second change gear are the same in size.