CN215017316U

CN215017316U - Arm fixing device

Info

Publication number: CN215017316U
Application number: CN202120297447.5U
Authority: CN
Inventors: 王思亮; 王敏
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-02-02
Filing date: 2021-02-02
Publication date: 2021-12-07
Anticipated expiration: 2031-02-02

Abstract

The utility model provides an arm fixing device relates to medical instrument technical field. This arm fixing device mainly includes the backup pad, holds in the palm the wrist pad, bandage and elevating gear, adjusts the relative height between backup pad and the support wrist pad through elevating gear, and backup pad and the crossing position of support wrist pad are wrist portion, thereby utilize the height amplitude who holds in the palm the wrist pad to adjust the bending angle of wrist portion, make the wrist fully expose and tighten radial artery, increase the success rate of puncture, alleviate the misery that causes the patient because of puncturing repeatedly, improve patient's satisfaction and cooperation greatly. The bandage can fix the palm of the patient to prevent the patient from avoiding and shaking to cause the displacement of the puncture point in the process of puncturing.

Description

Arm fixing device

Technical Field

The utility model relates to the technical field of medical equipment, particularly, relate to an arm fixing device.

Background

The invasive artery continuous pressure measurement is widely applied to the critical patient rescue, the heart, the brain, the lung and other large-scale operations, can accurately and timely find the hemodynamic fluctuation and guide medical care personnel to treat the disease condition at the first time, and overcomes the defects that the noninvasive cuff can not continuously measure the pressure, the data is delayed, the data is inaccurate and the like. The radial artery position is shallow in surface, strong in pulsation and convenient to puncture and fix, and is often used as the first choice for placing a tube for arterial puncture at present. The universal puncturing method is to dorsiflex the palm of the patient, pad an object under the wrist and fix the palm with an adhesive tape, so that the radial artery is exposed more clearly. Although the method is simple and practical, the object is easy to move in the process of puncture; and because the wrists of the patients are different in size and the dorsiflexion amplitude of the palms is different, the puncture success rate is lower, and the incidence rate of complications of repeated puncture is obviously increased. After one-time puncture fails, medical personnel need to press and stop bleeding at the puncture point for 5-10 minutes, thereby not only bringing physical and mental pains to patients, but also increasing the working strength of the medical personnel and greatly reducing the working efficiency.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an arm fixing device, it can help improving the puncture success rate, improves doctor-patient satisfaction.

The embodiment of the utility model is realized like this:

the utility model provides an arm fixing device, its includes backup pad, bandage and holds in the palm the wrist pad, and the bandage is installed and is used for the constraint patient's palm in the backup pad, is equipped with between backup pad and the wrist pad to be used for adjusting and holds in the palm elevating gear of wrist pad height.

In some embodiments of the present invention, the lifting device includes a housing, a rotating shaft and a screw rod, one end of the rotating shaft and one end of the screw rod are located in the housing, a nut is sleeved on the screw rod extending out of one end of the housing, and the nut is connected with the wrist supporting pad; the screw rod sleeve that is located casing one end is equipped with fixed connection's first bevel gear, and the cover is equipped with the second bevel gear with first bevel gear intermeshing on the rotation axis, and the casing is connected with the backup pad.

In some embodiments of the present invention, the arm fixing device further includes a bearing, and the bearing is disposed on the screw.

In some embodiments of the present invention, an arm fixing device further comprises a rocker, and the rocker is detachably connected to the rotation shaft.

The utility model discloses an in some embodiments, still include the slider that links to each other with the bandage, the both sides of following the bandage vertical direction and going up the backup pad are equipped with the spout, are equipped with the assorted slider in the spout, and the slider links to each other with the bandage, disposes the bolt that is used for the braking on the slider, and the slider passes through the bolt location in the backup pad.

In some embodiments of the present invention, the upper surface of the wrist pad is an outward convex arc.

In some embodiments of the present invention, the wrist supporting pad has air holes penetrating inside and outside.

In some embodiments of the present invention, the wrist pad has a cavity therein.

In some embodiments of the present invention, the surfaces of the wrist support pad and the support plate are provided with an antibacterial layer.

In some embodiments of the invention, the support plate is provided with a soft layer.

The embodiment of the utility model provides an at least, have following advantage or beneficial effect:

an embodiment of the utility model provides an arm fixing device, it includes backup pad, bandage and holds in the palm wrist pad. The backup pad is used for placing the arm, and the bandage is used for the constraint patient's palm, prevents that the patient from dodging, rocking and causing the puncture point to shift in carrying out the puncture process. The crossing position of backup pad and support wrist pad is the wrist portion, will support the wrist pad and place in wrist department and cooperate the bandage constraint patient palm, thereby make the wrist portion present certain angle, and the elevating gear who sets up between backup pad and the support wrist pad can make and support the wrist pad and rise or reduce, the crooked degree of the adjustable wrist portion of support wrist pad of different height ranges, make patient's wrist fully expose and tighten radial artery, make its vascular artery clear, be convenient for medical personnel puncture, increase the successful probability of puncture, alleviate the misery that causes the patient because of puncturing repeatedly, improve patient's satisfaction and cooperation greatly. In addition, the bending degree of the wrist part is different due to different dorsiflexion amplitudes of the palms of the patients. Therefore, the lifting device is arranged between the supporting plate and the wrist supporting pad, so that the problem of low matching degree of the wrist supporting pad is solved, the wrist bending degree required by different people is met, and the application range of the arm fixing device is expanded.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic view of an arm fixing device according to an embodiment of the present invention;

fig. 2 is a sectional view of a lifting device according to an embodiment of the present invention;

FIG. 3 is a schematic view of the connection of a rocker according to an embodiment of the present invention;

icon: 100-arm fixation means; 110-a support plate; 111-a slider; 112-bolt; 113-a chute; 130-a strap; 140-a rocker; 150-wrist support pad; 151-air holes; 161-screw rod; 163-a nut; 170-a lifting device; 171-a housing; 172-a second accommodating cavity; 173-first bevel gear; 174-axis of rotation; 175-a second bevel gear; 176-a first accommodating cavity; 177-a bearing; 178-limiting hole; 179-slot; 180-soft layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the embodiments of the present invention, it should be noted that, if the terms "center", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, the description is only for convenience of description, and the description is simplified, but the indication or suggestion that the indicated device or element must have a specific position, be constructed in a specific position and be operated, and thus, the present invention should not be construed as being limited.

Furthermore, the terms "horizontal", "vertical" and the like do not require that the components be absolutely horizontal or overhanging, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the embodiments of the present invention, it should be further noted that unless explicitly stated or limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Examples

Referring to fig. 1 and 2, fig. 1 is a schematic view of the arm fixing device 100, and fig. 2 is a sectional view of the lifting device 170.

The present embodiment provides an arm fixing device 100, which includes a supporting plate 110, a strap 130 and a wrist supporting pad 150. The support plate 110 is used for placing an arm, and the binding band 130 is used for binding the palm of the patient to prevent the displacement of the puncture point caused by the avoidance and shaking of the patient during the puncture process. Bandage 130 and wrist supporting pad 150 coplanar interval install on backup pad 110, backup pad 110 and the crossing position of wrist supporting pad 150 are the wrist portion, place wrist supporting pad 150 in wrist department and cooperate bandage 130 constraint patient's palm, thereby make the wrist portion present certain angle, and the crooked degree of the wrist supporting pad 150 adjustable wrist portion of different height ranges, make the wrist fully expose and tighten the radial artery, make its vascular artery clear, be convenient for medical personnel to puncture, increase one-time puncture success rate, alleviate the misery that causes the patient because of puncturing repeatedly, improve patient's satisfaction and cooperation degree greatly.

In the use process, the bending angles of the wrists of the patients are different due to different wrist sizes and different dorsiflexion amplitudes of the palms. Therefore, the lifting device 170 is disposed between the supporting plate 110 and the wrist supporting pad 150 to solve the problem of low height matching degree of the wrist supporting pad 150. In this embodiment, the lifting device 170 includes a screw 161 and a nut 163, the nut 163 is installed on the screw 161, one end of the screw 161 is connected to the support plate 110, the other end of the screw 161 is connected to the nut 163 through a screw, and the nut 163 is connected to the wrist supporting pad 150. When the wrist supporting device is used, the nut 163 is lifted or lowered by the rotation of the screw 161, and then the wrist supporting pad 150 connected with the nut 163 is lifted or lowered, so that the wrist bending degree required by different people is met, the radial artery is fully exposed and tightened, the success probability of one-time puncture is improved, and the application range of the arm fixing device 100 is expanded.

Further, the lifting device 170 comprises a housing 171, a rotating shaft 174 and a screw 161, one end of the rotating shaft 174 and one end of the screw 161 are located in the housing 171, a nut 163 is sleeved on the screw 161 extending out of one end of the housing 171, and the nut 163 is connected with the wrist supporting pad 150; the screw 161 at one end of the housing 171 is sleeved with a first bevel gear 173 fixedly connected, the rotating shaft 174 is sleeved with a second bevel gear 175 engaged with the first bevel gear 173, and the housing 171 is connected with the support plate 110. In detail, the fixing head includes a housing 171, a first bevel gear 173, a second bevel gear 175, and a bearing 177 in this embodiment, and the housing 171 is coupled with the support plate 110. The fixed end is provided with a first receiving cavity 176 for receiving the first and

second bevel gears

173 and 175, and the first receiving cavity 176 is provided with a horizontal rotating shaft 174. One end of the rotary shaft 174 is inserted through a center of the second bevel gear 175 and is mounted to a left stopper hole 178 (which overlaps the rotary shaft 174 in the drawing) of the housing 171, and the other end of the rotary shaft 174 is inserted through a right stopper hole 178 of the housing 171. Further, the housing 171 is provided with a second accommodation chamber 172 accommodating the screw 161, and the first accommodation chamber 176 and the second accommodation chamber 172 communicate. The first bevel gear 173 and the second bevel gear 175 are engaged with each other, and the first bevel gear 173 is coaxially and fixedly connected with the screw 161. The screw 161 is connected with the nut 163 through threads, the nut 163 is connected with the wrist supporting pad 150, and the housing 171 is connected with the supporting plate 110. In use, the second bevel gear 175 is rotated by the rotation shaft 174, and the first bevel gear 173 is rotated by the engagement between the gears. At this time, since the first bevel gear 173 is fixedly connected to the screw 161, the screw 161 is rotated by the rotation of the first bevel gear 173.

Further, a bearing 177 is arranged in the second accommodating cavity 172, an outer ring of the bearing 177 is fixedly connected with the housing 171, and the screw 161 is arranged at an inner ring of the bearing 177. The bearing 177 is provided to ensure stability of the screw 161, prevent the screw 161 from being displaced, reduce friction between the screw 161 and the housing 171, and allow the screw 161 to rotate with a small force applied to the rotary shaft 174. The rotation of the screw 161 drives the nut 163 to move vertically, and the housing 171 is connected to the support plate 110, so that the wrist supporting pad 150 connected to the nut 163 is raised or lowered relative to the support plate 110. The lifting device 170 is compact in structure, convenient to install, capable of adjusting the height conveniently and efficiently, time-saving and labor-saving in use, and ingenious in connection among all the components of the overall structure.

Referring to fig. 3, fig. 3 is a schematic connection diagram of the rocker 140.

In order to facilitate and save labor for adjusting the height of the wrist pad 150, the arm fixing device 100 further comprises a rocker 140, and the rocker 140 is detachably connected with the rotating shaft 174. For example, a slot 179 is provided on the right side of the rotary shaft 174 on the side protruding out of the housing 171. It should be noted that the slot 179 is non-circular in shape, and a side section of the rocker 140 matches the slot 179. In the present embodiment, the slot 179 is hexagonal. During the use, insert the rocker 140 in the slot 179, carry out the joint through hexagonal edges and corners, wave rocker 140 and drive gear revolve, the transmission between the rethread gear makes screw 161 rotate to drive nut 163 and rise or descend, and then realize holding in the palm the altitude mixture control of wrist pad 150. When the rocking bar 140 is removed, the friction angle between the nut 163 and the screw 161 is large, so that the nut 163 and the screw 161 can be self-locked, thereby preventing the wrist support pad 150 from sliding downwards under the action of gravity, and omitting the fixing step after the wrist support pad 150 is adjusted to the required height. In other embodiments, a through hole (not shown) is formed in the rotating shaft 174 on the side protruding out of the housing 171 and extends in and out in the vertical direction, and a vertical rocker 140 is inserted into the through hole and rotated about the rotating shaft 174 as a fulcrum, so that the rotating shaft 174 rotates and is driven by a series of driving mechanisms, thereby raising or lowering the wrist pad 150.

In order to make the binding band 130 more suitable for people with different arm lengths, the sliding grooves 113 are formed in the two sides of the supporting plate 110 in the vertical direction of the binding band 130, the sliding blocks 111 matched with the sliding grooves 113 are arranged in the sliding grooves 113, and the sliding blocks 111 are connected with the binding band 130. The slider 111 is provided with a bolt 112 for stopping, and the slider 111 is positioned on the support plate 110 by the bolt 112. In this embodiment, the strap 130 is an elastic band. In detail, the sliding block 111 is installed in the sliding groove 113, a gap is formed on one side of the sliding groove 113 away from the supporting plate 110, and the binding band 130 is connected to the sliding block 111, extends out of the gap, and is connected to the sliding block 111 on the other side. Further, a bolt 112 for braking is disposed on the slider 111, and a screw groove (not shown) is provided on the slide groove 113 to be matched with the bolt 112, and the screw groove communicates with the slide groove 113. The sliding block 111 is provided with a threaded hole (not shown), the bolt 112 is screwed through the threaded hole, the threaded end of the bolt 112 abuts against the inner wall of the sliding slot 113, and the sliding block 111 is positioned on the supporting plate 110. When the medical bandage is used, the bolt 112 is unscrewed, so that the sliding block 111 slides to the palm of the patient in the sliding groove 113, and then the bolt 112 is screwed and fixed on the supporting plate 110, so that the position of the bandage 130 on the supporting plate 110 is more stable, and the slippage phenomenon is not easy to occur. The position of the sliding block 111 on the supporting plate 110 is adjusted, so that the arm length of different people can be adjusted, and the application range of the arm length adjusting device is expanded. In addition, the strap 130 may cause nerve damage when being tightened on the same part of the patient for a long time, and in order to avoid the hidden trouble caused by the strap 130, a layer of sponge (not shown in the figure) is arranged on the side, which is attached to the skin, of the strap 130, so that the pressure of the strap 130 on the palm is relieved, and the nerves in the palm are protected.

In order to improve the comfort of the arm fixing device 100 and give the patient a better experience, the upper surface of the wrist supporting pad 150 is of an outward convex arc shape. The curved shape of the wrist supporting pad 150 makes the wrist more suitable for the connection of the palm, the wrist and the arm of the human body when the wrist is lifted, thereby improving the comfort of the arm fixing device 100. Further, the upper surface of the wrist supporting pad 150 is recessed inwards, and the arms are placed in the recessed positions, so that the contact surfaces of the arms, the wrist supporting pad 150 and the supporting plate 110 are larger, the comfort of a patient is improved, meanwhile, the friction force between the arms and the wrist supporting pad 150 can be increased, and the arms are prevented from shaking.

In the metabolic process of a human body, body surface cells can exchange gas with the external environment, and meanwhile, heat is dissipated through sweating so as to adjust the body temperature of the human body. However, under the influence of mental factors such as stress, fear and excitation, nerve impulse is transmitted from cerebral cortex to palmar and palmar eccrine gland parts, and the concentration of norepinephrine is increased, so that the secretion and excretion activities of the eccrine gland are rapidly enhanced in a short period, namely, psychogenic sweating is generated. In addition, the air tightness of the area in contact with the arms also causes skin sweating, which is likely to cause bacterial growth. Therefore, in order to improve the ventilation of the arm fixing device 100 and thus the comfort of the patient, the wrist supporting pad 150 has ventilation holes 151 formed on the surface thereof to penetrate inside and outside. Can reduce the production of sweat, guarantee that the patient body surface is in comparatively dry state to satisfy the requirement of its travelling comfort, can reduce breeding of bacterium again, avoid the patient to infect at the operation in-process.

In daily life, certain bacteria and viruses exist in the environment. If the needle is not disinfected before operation, the needle can puncture skin to form a wound surface, bacteria and viruses enter a human body, and the probability of infection of the human body is increased. In order to create a sterile operation environment, the wrist pad 150 and the support plate 110 are provided with an antibacterial layer (not shown) on their surfaces to resist bacteria and viruses from outside, so as to effectively prevent bacteria from entering the body for a long time and prevent bacteria from entering the body smoothly through the wound surface during the operation to cause infection. In this embodiment, the antibacterial layer is a nano titanium dioxide composite film.

In detail, semiconductor nano titanium dioxide is a photocatalytic antibacterial agent, when light with energy larger than band gap energy irradiates the surface of the semiconductor nano titanium dioxide, electrons in a low-energy valence band of the semiconductor nano titanium dioxide can be excited to jump to a high-energy conduction band, so that active oxygen groups are generated, and the active groups have super-strong oxidizing capability and are key substances for degrading organic matters. The reactive oxygen species can directly attack microbial cells, destroy the cytoplasmic membrane and internal organelles, cause cell permeability disorder, promote cell death and effectively inactivate microorganisms. Moreover, the film has good flexibility, can be well contacted with the wrist supporting pad 150 and the supporting plate 110, avoids the nano titanium dioxide composite film from sliding due to external action, can avoid cross infection for different patients by only replacing the nano titanium dioxide composite film, and improves the safety of the operation. The nano titanium dioxide composite film can be directly pasted, and is simple and quick to replace. Of course, in other embodiments, other antibacterial layers may be used as long as the antibacterial effect can be achieved, and the antibacterial layer is not limited specifically.

After the operation, hematoma may occur after the operation, swelling and pain may occur when anesthesia disappears, and in order to effectively reduce the swelling and pain of the affected limb as soon as possible, a cavity 152 (not shown in the figure) is formed in the wrist support pad 150 in the present embodiment, and then an ice block or an ice bag is placed in the cavity 152 for local cold compress, thereby achieving the effects of stopping bleeding and relieving pain. In detail, the ethanol salt ice water bag is adopted in the embodiment, the ice bag can obviously prolong the low-temperature time of the ice bag, the bag body is soft and can be molded at will, the ice bag is easy to fix with the arm of a patient and fully contacts with the body surface, the local temperature is quickly reduced, the sensitivity of nerve endings is reduced, the blood vessels of the wound surface are contracted, the paralysis effect is effectively achieved, the postoperative complications are relieved, and the pain and the bleeding are stopped. Of course, ice blocks can be used for relieving pain during operation, but the amount of ice needs to be paid attention to, so that certain harm to human bodies due to low body temperature during operation is avoided. Further, in order to prevent the ice pack from directly contacting the skin to cause frostbite, a sponge layer or a non-woven fabric layer may be disposed in the cavity 152.

Referring to fig. 1, fig. 1 is a schematic view of an arm fixing device 100.

In order to protect the skin of the patient, the support plate 110 is provided with a soft layer 180. In this embodiment, the soft layer 180 is a high-density sponge with better supporting force. The sponge is a porous material, has good water absorption, and can absorb sweat on the body surface of a patient, so that the patient is in a comfortable state all the time. Meanwhile, the sponge is soft in touch and has certain ductility, so that the skin of a patient is protected, the contact area between the arm and the soft layer 180 is increased, the friction force is increased, the displacement of the puncture point caused by the shaking of the patient when the arm punctures can be effectively avoided, and the probability of one-time successful puncture is improved. Optionally, the soft layer 180 may also be made of rubber, which has a reversibly deformable high-elasticity polymer material, and is elastic at room temperature, so that it can fit the arm of the patient well, thereby increasing the comfort of the patient and achieving a better anti-slip effect.

The working principle of the arm fixing device 100 is as follows:

the arm fixing device 100 comprises a support plate 110, a strap 130 and a wrist supporting pad 150, wherein the strap 130 can fix the palm of the patient to prevent the patient from escaping and shaking during the puncturing process to cause the puncturing point to shift. The relative height between the support plate 110 and the wrist supporting pad 150 is adjusted by the lifting device 170, and the position where the support plate 110 and the wrist supporting pad 150 intersect is the wrist portion. The band 130 is matched with the height and the amplitude of the wrist supporting pad 150 to adjust the bending degree of the wrist part, so that the wrist part is fully exposed and the radial artery is tightened, the puncture success rate is increased, the pain of a patient caused by repeated puncture is relieved, and the satisfaction degree and the matching degree of the patient are greatly improved. The lifting device 170 disposed between the supporting plate 110 and the wrist supporting pad 150 solves the problem of low height matching degree of the wrist supporting pad 150, so as to satisfy the wrist bending degree required by different patients with different wrist sizes and different palm dorsiflexion amplitudes, and expand the application range of the arm fixing device 100.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An arm fixing device is characterized by comprising a supporting plate, a binding band and a wrist supporting pad, wherein the binding band is installed on the supporting plate and used for binding the palm of a patient, and a lifting device used for adjusting the height of the wrist supporting pad is arranged between the supporting plate and the wrist supporting pad.

2. The arm fixing device according to claim 1, wherein the lifting device comprises a housing, a rotating shaft and a screw rod, one end of the rotating shaft and one end of the screw rod are positioned in the housing, a nut is sleeved on the screw rod extending out of one end of the housing, and the nut is connected with the wrist supporting pad; the screw rod sleeve positioned at one end in the shell is provided with a first bevel gear which is fixedly connected, the rotating shaft is provided with a second bevel gear which is meshed with the first bevel gear in a sleeved mode, and the shell is connected with the supporting plate.

3. An arm fixing device according to claim 2, further comprising a bearing, wherein the bearing is sleeved on the screw.

4. An arm fixing device according to claim 2, further comprising a rocking bar, wherein the rocking bar is detachably connected to the rotary shaft.

5. An arm fixing device according to claim 1, wherein sliding grooves are formed along both sides of the support plate in the vertical direction of the binding band, matching sliding blocks are arranged in the sliding grooves, the sliding blocks are connected with the binding band, bolts for braking are arranged on the sliding blocks, and the sliding blocks are positioned on the support plate through the bolts.

6. An arm fixing device according to claim 1, wherein the upper surface of said wrist supporting pad is convex arc-shaped.

7. An arm fixing device according to claim 1, wherein the wrist supporting pad is provided with air holes on the surface.

8. An arm fixing device according to claim 7, wherein the wrist supporting pad has a cavity therein.

9. An arm fixing device according to claim 1, wherein the wrist supporting pad and the supporting plate are provided with an antibacterial layer on their surfaces.

10. An arm fixing device according to claim 1, wherein said support plate is provided with a soft layer.