A medical assisted breathing device

Abstract

The present invention relates to a medical auxiliary breathing device. The technical problem of the present invention is that the current breathing assistance device is not convenient to adjust according to the nostril spacing of the patient, nor is it convenient to seal nostrils with different apertures, and it is not convenient to well assist the patient in breathing. A medical auxiliary breathing device includes a U-shaped rubber tube, a plate buckle, a strap, etc.; two plate buckles are installed on the side of the U-shaped rubber tube, and a strap is connected between the two plate buckles. Through gas entering the two hollow sleeves, the two hollow sleeves are attached to the inner side walls of the two nostrils of the patient, so as to maintain the expansion amplitude of the two hollow sleeves, thereby improving the applicable range of the device, enabling patients with different nostril apertures to obtain good airtightness in their nostrils when using the device, thus avoiding gas leakage and waste of gas when the patient inhales, and at the same time improving the comfort of the patient when inhaling.

Description

Technical Field

[0001] The present invention relates to the medical field, and particularly to a medical auxiliary breathing device. Background Art

[0002] Good warming and humidification can prevent and reduce secondary respiratory tract infections in mechanically ventilated patients, as well as the stimulation to the cardiopulmonary system, and keep the alveoli moist. At the same time, it can also reduce the consumption of heat and respiratory tract moisture, making it difficult for sputum crusts to form in the airway, and can reduce the viscosity of secretions, promoting expectoration.

[0003] Since the nostril spacings and apertures of different patients are different, and the current respiratory assistance devices are not convenient to adjust according to the nostril spacings of patients, nor are they convenient to seal nostrils with different apertures. Gas is likely to leak, resulting in waste. At the same time, the comfort of patients during inhalation is not enough, and it is not convenient to assist patients in breathing well. Summary of the Invention

[0004] In order to overcome the disadvantages that the current respiratory assistance devices are not convenient to adjust according to the nostril spacings of patients and are not convenient to seal nostrils with different apertures, in view of this, the present invention provides a medical auxiliary breathing device, which can be adjusted according to the nostril spacings of patients, can also seal nostrils with different apertures, reduce gas leakage, and improve the comfort of patients during use.

[0005] Technical Solution: A medical auxiliary breathing device includes a U-shaped rubber tube, plate buckles, straps, connecting tubes, connectors, bellows, expansion mechanisms, and driving mechanisms. Two plate buckles are installed on the side of the U-shaped rubber tube, and a strap is connected between the two plate buckles. A connecting tube is installed in the middle of the U-shaped rubber tube, and the connecting tube is communicated with the U-shaped rubber tube. One end of the connecting tube is threadedly connected with a connector, and the connecting tube is communicated with the connector. A bellows is connected to the connector, and the bellows is communicated with the connector. An expansion mechanism is provided at each end of the U-shaped rubber tube, and the expansion mechanism is used to seal the nostrils after expansion. A driving mechanism is provided on the U-shaped rubber tube and the expansion mechanism, and the driving mechanism is used to drive the expansion mechanism to operate.

[0006] In addition, particularly preferably, the expansion mechanism includes ball head tubes, hollow sleeves, and valve bodies. A ball head tube is installed at each end of the U-shaped rubber tube. Two convex rings are respectively provided on the two ball head tubes. The two ball head tubes are communicated with the U-shaped rubber tube. A plurality of through holes are opened on one side of the two ball head tubes close to each other, and the through holes are located between the two convex rings on the ball head tubes. A hollow sleeve is sleeved at the end of each of the two ball head tubes. A plurality of slotted holes are evenly spaced in the inner ring of the two hollow sleeves, and the through holes are communicated with the slotted holes. A valve body is rotatably provided on one side of each of the two ball head tubes close to the through holes, and a groove is provided on the valve body, and the groove is communicated with the through hole.

[0007] In addition, it is particularly preferred that the material of the hollow sleeve is silicone material.

[0008] In addition, it is particularly preferred that the drive mechanism includes a pipe body, a rotating rod, a hexagonal rod and a hexagonal hole pipe. Two pipe bodies are fixedly installed on the U-shaped rubber pipe. One rotating rod is rotatably provided on each side of the two pipe bodies close to the ball head pipe. One end of the two rotating rods close to the ball head pipe is connected to the two valve bodies by bolts. One hexagonal rod is fixedly installed at one end of the two rotating rods away from the ball head pipe. The hexagonal rod is located inside the pipe body. One hexagonal hole pipe is rotatably provided on each side of the two pipe bodies away from the ball head pipe. The hexagonal rod is slidably connected to the hexagonal hole pipe.

[0009] In addition, it is particularly preferred that a rotating mechanism is further included. The rotating mechanism is arranged on the pipe body and the hexagonal hole pipe. The rotating mechanism is used to drive the valve body to rotate. The rotating mechanism includes a protrusion. A spiral groove is respectively opened in each of the two pipe bodies. A protrusion is provided on each of the two hexagonal hole pipes. The protrusion is located in the spiral groove.

[0010] In addition, it is particularly preferred that a fixed magnet ring and a movable magnet ring are further included. A fixed magnet ring is installed at one end of the two pipe bodies away from the ball head pipe. A movable magnet ring is fixedly installed on one side of the two hexagonal hole pipes away from the pipe body.

[0011] In addition, it is particularly preferred that the sides of the fixed magnet ring and the movable magnet ring close to each other have opposite magnetic polarities.

[0012] In addition, it is particularly preferred that a finger rest is further included. A finger rest is rotatably provided at one end of the two hexagonal hole pipes away from the ball head pipe.

[0013] In addition, it is particularly preferred that the sides of the two finger rests away from the hexagonal hole pipes are recessed, and the recessed parts of the two finger rests are rough surfaces.

[0014] The beneficial effects of the present invention are as follows: 1. By allowing gas to enter the two hollow sleeves, the two hollow sleeves are made to fit against the inner walls of the two nostrils of the patient. Then, the two valve bodies are rotated, and the through holes are sealed by the other side of the valve bodies. In this way, the gas in the two hollow sleeves will no longer be discharged, so as to maintain the expansion amplitude of the two hollow sleeves, thereby expanding the applicable range of the present device, enabling patients with different nostril apertures to obtain good airtightness when using the present device, thus avoiding gas leakage during the patient's inhalation and resulting in waste of gas, and at the same time improving the comfort of the patient during inhalation.

[0015] 2. By pressing the finger rest, the through hole can be closed while correcting the position of the hollow sleeve, keeping the hollow sleeve in an expanded state, so that the through hole can be quickly closed, better controlling the expansion amplitude of the hollow sleeve. While ensuring the airtightness of the nostrils after the hollow sleeve expands, the comfort of the patient during use is improved. By pulling the finger rest, the two hollow sleeves can be pulled while the through hole is connected, enabling the two hollow sleeves to be taken out more conveniently and quickly, making the device more convenient to use.

[0016] 3. The movable magnet ring and the fixed magnet ring adsorb each other to limit the hexagonal hole tube, preventing the patient from accidentally touching and pulling the hexagonal hole tube, which may cause the valve body to rotate and the hollow sleeve to contract, resulting in the loss of airtightness of the nostrils. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0018] Figure 2 It is a three-dimensional structural schematic diagram of the expansion mechanism and the drive mechanism of the present invention.

[0019] Figure 3 It is a three-dimensional structural schematic diagram of the U-shaped rubber tube, the ball head tube and the hollow sleeve of the present invention.

[0020] Figure 4 It is a sectional three-dimensional structural schematic diagram of the expansion mechanism of the present invention.

[0021] Figure 5 It is a three-dimensional structural schematic diagram of the ball head tube, the through hole, the hollow sleeve and the one-word hole of the present invention.

[0022] Figure 6 It is a sectional three-dimensional structural schematic diagram of the expansion mechanism and the drive mechanism of the present invention.

[0023] Figure 7 It is a three-dimensional structural schematic diagram of the ball head tube, the hollow sleeve and the valve body of the present invention.

[0024] Figure 8 It is a three-dimensional structural schematic diagram of the drive mechanism of the present invention.

[0025] Figure 9 It is a sectional three-dimensional structural schematic diagram of the drive mechanism of the present invention.

[0026] Figure 10 It is a disassembled three-dimensional structural schematic diagram of some parts of the expansion mechanism and the drive mechanism of the present invention.

[0027] Figure 11 It is a sectional three-dimensional structural schematic diagram of the ball head tube, the hollow sleeve and the tube body of the present invention.

[0028] In the figure: 1. U-shaped rubber tube, 2. Plate buckle, 3. Binding strap, 4. Connecting tube, 5. Joint, 6. Bellows, 71. Ball head tube, 72. Through hole, 73. Hollow sleeve, 74. One-way hole, 75. Valve body, 81. Tube body, 82. Rotating rod, 83. Hexagonal rod, 84. Hexagonal hole tube, 91. Spiral groove, 92. Protrusion, 101. Fixed magnet ring, 102. Movable magnet ring, 11. Finger support. Detailed implementation mode

[0029] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in combination with the specific implementation modes and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following descriptions, the descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0030] Embodiment 1:

[0031] The embodiment of the present invention provides a medical auxiliary breathing device, as Figures 1 - 11 shown, including a U-shaped rubber tube 1, a plate buckle 2, a binding strap 3, a connecting tube 4, a joint 5, a bellows 6, an expansion mechanism and a driving mechanism. Two plate buckles 2 are installed on the side of the U-shaped rubber tube 1 through bolts, and a binding strap 3 is connected between the two plate buckles 2. A connecting tube 4 is installed in the middle of the U-shaped rubber tube 1; the connecting tube 4 is communicated with the U-shaped rubber tube 1, and one end of the connecting tube 4 is threadedly connected with a joint 5, and the connecting tube 4 is communicated with the joint 5; a bellows 6 is connected to the joint 5, and the bellows 6 is communicated with the joint 5; both ends of the U-shaped rubber tube 1 are respectively provided with an expansion mechanism;

[0032] The expansion mechanism is used to seal the nostrils after expansion. A driving mechanism is provided on the U-shaped rubber tube 1 and the expansion mechanism, and the driving mechanism is used to drive the expansion mechanism to operate.

[0033] Among them, the expansion mechanism includes a ball head tube 71, a hollow sleeve 73 and a valve body 75. A ball head tube 71 is installed at both ends of the U-shaped rubber tube 1 respectively. Two convex rings are respectively arranged on the two ball head tubes 71, and the two ball head tubes 71 are communicated with the U-shaped rubber tube 1; a plurality of through holes 72 are opened on the side of the two ball head tubes 71 close to each other, and the through holes 72 are located between the two convex rings on the ball head tube 71; the ends of the two ball head tubes 71 are respectively sleeved with a hollow sleeve 73; a plurality of one-way holes 74 are evenly spaced in the inner rings of the two hollow sleeves 73, the through holes 72 are communicated with the one-way holes 74, and a valve body 75 is rotatably arranged on the side of the two ball head tubes 71 close to the through holes 72, and a groove is arranged on the valve body 75, and the groove is communicated with the through holes 72.

[0034] The material of the hollow sleeve 73 is silicone material.

[0035] The above-mentioned driving mechanism includes a pipe body 81, a rotating rod 82, a hexagonal rod 83 and a hexagonal hole pipe 84. Two pipe bodies 81 are fixedly installed on the U-shaped rubber pipe 1. One rotating rod 82 is rotatably arranged on each of the two pipe bodies 81 near one side of the ball head pipe 71. One end of each of the two rotating rods 82 near the ball head pipe 71 is connected to the two valve bodies 75 by bolts; one hexagonal rod 83 is fixedly installed at one end of each of the two rotating rods 82 far from the ball head pipe 71, and the hexagonal rod 83 is located inside the pipe body 81; one hexagonal hole pipe 84 is rotatably arranged on each of the two pipe bodies 81 far from the ball head pipe 71, and the hexagonal rod 83 is slidably connected to the hexagonal hole pipe 84, and the hexagonal rod 83 slides in the hexagonal hole pipe 84.

[0036] Initially, the two ball head pipes 71 are closed by the two valve bodies 75. When the patient needs assisted breathing, first insert the two hollow sleeves 73 into the two nostrils of the patient; under the action of the toughness of the U-shaped rubber pipe 1, the positions of the two hollow sleeves 73 can be finely adjusted, so that the two hollow sleeves 73 are more accurately aligned with the two nostrils of the patient. Then, fix the device on the patient's head through the strap 3. Subsequently, humidified and heated gas is introduced into the corrugated pipe 6. The gas enters the U-shaped rubber pipe 1 through the joint 5 and the connecting pipe 4. The gas enters the two hollow sleeves 73 through the through hole 72 and the linear hole 74; the two hollow sleeves 73 will expand. After the two hollow sleeves 73 are attached to the inner side walls of the two nostrils of the patient, the patient rotates the two hexagonal hole pipes 84. The two hexagonal hole pipes 84 drive the two hexagonal rods 83 and the two rotating rods 82 to rotate. The two rotating rods 82 drive the two valve bodies 75 to rotate; the grooves of the two valve bodies 75 no longer communicate with the through hole 72 after rotation; the through hole 72 is sealed by the other side of the valve body 75. In this way, the gas in the two hollow sleeves 73 will no longer be discharged, so as to maintain the expansion amplitude of the two hollow sleeves 73. The two hollow sleeves 73 are communicated with the two ball head pipes 71 through the grooves of the two valve bodies 75. The gas is discharged into the patient's nostrils through the grooves of the two valve bodies 75. The patient inhales through the nostrils and breathes through the mouth. In this way, the breathing assistance for the patient is completed;

[0037] After the patient finishes inhaling, first stop supplying gas, and then rotate the two hexagonal hole pipes 84 in the reverse direction. The two hexagonal hole pipes 84 drive the two hexagonal rods 83 and the two rotating rods 82 to rotate in the reverse direction. The two rotating rods 82 drive the two valve bodies 75 to rotate in the reverse direction. The grooves of the two valve bodies 75 communicate with the through hole 72 again after rotation. Under the elastic action of the two hollow sleeves 73, the gas in the two hollow sleeves 73 is discharged into the U-shaped rubber pipe 1 through the linear hole 74 and the through hole 72, so that the two hollow sleeves 73 return to the initial state, and the two valve bodies 75 will close the two ball head pipes 71 again after rotation;

[0038] After the hollow sleeve 73 has been used for a period of time, the operator removes the used hollow sleeve 73 and then puts a new hollow sleeve 73 on the ball head tube 71. Since a circle of slot holes 74 are evenly spaced in the inner ring of the hollow sleeve 73, no adjustment is required after the hollow sleeve 73 is put on, and the slot holes 74 can also communicate with the through holes 72, improving the replacement efficiency of the hollow sleeve 73. By the two convex rings on the ball head tube 71 fitting with the hollow sleeve 73, the hollow sleeve 73 can be made not easy to fall off; by gas entering the two hollow sleeves 73, the two hollow sleeves 73 are made to fit with the inner side walls of the two nostrils of the patient, and then the two valve bodies 75 are rotated, and the through holes 72 are sealed through the other sides of the valve bodies 75, so that the gas in the two hollow sleeves 73 will no longer be discharged, thus maintaining the expansion amplitude of the two hollow sleeves 73, and further improving the applicable range of the device; enabling patients with different nostril apertures to obtain good airtightness in the nostrils when using the device, thus avoiding waste of gas caused by gas leakage when the patient inhales; and at the same time, it can also improve the comfort of the patient when inhaling.

[0039] Embodiment 2: On the basis of Embodiment 1, as Figures 6 - 11 shown, it further includes a rotating mechanism, and the rotating mechanism is arranged on the tube body 81 and the hexagonal hole tube 84; the rotating mechanism is used to drive the valve body 75 to rotate, and the rotating mechanism includes a protrusion 92. A spiral groove 91 is respectively opened in each of the two tube bodies 81, and a protrusion 92 is provided on each of the two hexagonal hole tubes 84, and the protrusion 92 is located in the spiral groove 91.

[0040] It further includes a finger rest 11. A finger rest 11 is rotatably provided at one end of each of the two hexagonal hole tubes 84 far from the ball head tube 71 through a bearing.

[0041] One side of each of the two finger rests 11 far from the hexagonal hole tube 84 is recessed, and the recessed parts of the two finger rests 11 are provided with rough surfaces.

[0042] After the two hollow sleeves 73 expand and fit against the inner walls of the patient's two nostrils, when the patient's nostrils are filled and sealed, the patient presses the finger rest 11 with a finger to move it in the direction closer to the U-shaped rubber tube 1. While pressing, it can also push the two hollow sleeves 73 to the designated positions of the patient's two nostrils again, preventing the two hollow sleeves 73 from not reaching the designated positions of the nostrils and affecting the airtightness of the nostrils. The finger rest 11 drives the hexagonal hole tube 84 and the protrusion 92 to move in the direction closer to the U-shaped rubber tube 1, and the protrusion 92 slides in the spiral groove 91; under the guiding action of the spiral groove 91, the protrusion 92 rotates while moving, and the protrusion 92 drives the hexagonal hole tube 84 to rotate while moving. When the hexagonal hole tube 84 rotates, the finger rest 11 does not rotate. The hexagonal hole tube 84 drives the hexagonal rod 83, the rotating rod 82 and the valve body 75 to rotate. In this way, the through hole 72 can be closed while correcting the position of the hollow sleeve 73, keeping the hollow sleeve 73 in an expanded state. After the patient finishes inhaling, the patient pulls the finger rest 11 to move it in the direction away from the U-shaped rubber tube 1. While pulling, it can also pull the two hollow sleeves 73, making the two hollow sleeves 73 tend to move out of the nostrils. The finger rest 11 drives the hexagonal hole tube 84 and the protrusion 92 to move in the direction away from the U-shaped rubber tube 1, and the protrusion 92 slides in the spiral groove 91; under the guiding action of the spiral groove 91, the protrusion 92 rotates in the reverse direction while moving, and the protrusion 92 drives the hexagonal hole tube 84 to rotate in the reverse direction while moving. When the hexagonal hole tube 84 rotates, the finger rest 11 does not rotate. The hexagonal hole tube 84 drives the hexagonal rod 83, the rotating rod 82 and the valve body 75 to rotate in the reverse direction. In this way, the through hole 72 can be connected while pulling the two hollow sleeves 73, and the two hollow sleeves 73 can be taken out more conveniently and quickly; by pressing the finger rest 11, the through hole 72 can be closed while correcting the position of the hollow sleeve 73, keeping the hollow sleeve 73 in an expanded state, so that the through hole 72 can be quickly closed, better controlling the expansion amplitude of the hollow sleeve 73, improving the comfort of the patient while ensuring the airtightness of the nostrils after the hollow sleeve 73 expands. By pulling the finger rest 11, the through hole 72 can be connected while pulling the two hollow sleeves 73, and the two hollow sleeves 73 can be taken out more conveniently and quickly, making the device more convenient to use.

[0043] Embodiment Three:

[0044] Based on Embodiment Two, as Figures 6 - 11 shown, it further includes a fixed magnet ring 101 and a movable magnet ring 102. A fixed magnet ring 101 is installed at one end of each of the two pipe bodies 81 away from the ball head pipe 71, and a movable magnet ring 102 is fixedly installed on one side of each of the two hexagonal hole pipes 84 away from the pipe body 81.

[0045] The sides of the fixed magnet ring 101 and the movable magnet ring 102 that are close to each other have opposite magnetic polarities.

[0046] The hexagonal hole tube 84 moves towards the U-shaped rubber tube 1, driving the movable magnet ring 102 to move. When the hexagonal hole tube 84 is in place, the movable magnet ring 102 and the fixed magnet ring 101 attract each other. The hexagonal hole tube 84 moves away from the U-shaped rubber tube 1, driving the movable magnet ring 102 to move, and the movable magnet ring 102 will separate from the fixed magnet ring 101. By the mutual attraction of the movable magnet ring 102 and the fixed magnet ring 101, the hexagonal hole tube 84 is limited in position, preventing the patient from accidentally touching and pulling the hexagonal hole tube 84, which may cause the valve body 75 to rotate, and preventing the hollow sleeve 73 from contracting and losing the airtightness of the nostrils.

[0047] It should be understood that this embodiment is only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

Claims

1. A medical assisted breathing device, characterized in that: The invention comprises a U-shaped rubber tube (1), a plate buckle (2), a binding belt (3), a connecting tube (4), a joint (5), a bellows (6), an expansion mechanism and a driving mechanism. Two plate buckles (2) are installed on the side of the U-shaped rubber tube (1). A binding belt (3) is connected between the two plate buckles (2). A connecting tube (4) is installed in the middle of the U-shaped rubber tube (1). The connecting tube (4) is connected to the U-shaped rubber tube (1). A joint (5) is threadedly connected to one end of the connecting tube (4). The connecting tube (4) is connected to the joint (5). A bellows (6) is connected to the joint (5). The bellows (6) is connected to the joint (5). An expansion mechanism is respectively provided at both ends of the U-shaped rubber tube (1). The expansion mechanism is used to seal the nostrils after expansion. The U-shaped rubber tube (1) and the expansion mechanism are provided with a driving mechanism. The driving mechanism is used to drive the expansion mechanism to operate. The expansion mechanism comprises a ball head tube. (71), a hollow sleeve (73) and a valve body (75), a ball head tube (71) is respectively installed at both ends of the U-shaped rubber tube (1), two convex rings are respectively arranged on the two ball head tubes (71), the two ball head tubes (71) are communicated with the U-shaped rubber tube (1), a plurality of through holes (72) are opened on the sides of the two ball head tubes (71) close to each other, the through holes (72) are located between the two convex rings on the ball head tubes (71), a hollow sleeve (73) is respectively sleeved on the ends of the two ball head tubes (71), a plurality of slotted holes (74) are evenly spaced on the inner rings of the two hollow sleeves (73), the through holes (72) are communicated with the slotted holes (74), a valve body (75) is rotatably arranged on the sides of the two ball head tubes (71) close to the through holes (72), a groove is arranged on the valve body (75), and the groove is communicated with the through holes (72).

2. A medical assisted breathing device as claimed in claim 1, characterized in that: The hollow sleeve (73) is made of silica gel.

3. A medical assisted breathing device as claimed in claim 2, characterized in that: The driving mechanism comprises a tube body (81), a rotating rod (82), a hexagonal rod (83) and a hexagonal hole tube (84). Two tube bodies (81) are fixedly mounted on the U-shaped rubber tube (1). A rotating rod (82) is rotatably mounted on one side of the two tube bodies (81) close to the ball head tube (71). One end of the two rotating rods (82) close to the ball head tube (71) is connected to two valve bodies (75) through bolts. One end of the two rotating rods (82) away from the ball head tube (71) is fixedly mounted with a hexagonal rod (83). The hexagonal rod (83) is located in the tube body (81). One side of the two tube bodies (81) away from the ball head tube (71) is rotatably mounted with a hexagonal hole tube (84). The hexagonal rod (83) is slidably connected to the hexagonal hole tube (84).

4. A medical assisted breathing device as claimed in claim 3, characterized in that: The valve body (75) further comprises a rotating mechanism, which is arranged on the tube body (81) and the hexagonal hole tube (84). The rotating mechanism is used to drive the valve body (75) to rotate. The rotating mechanism comprises a protrusion (92). A spiral groove (91) is respectively opened in the two tube bodies (81). A protrusion (92) is provided on the two hexagonal hole tubes (84). The protrusion (92) is located in the spiral groove (91).

5. A medical respiratory assist device as claimed in claim 4, characterized in that: It also includes a fixed magnet ring (101) and a movable magnet ring (102). The fixed magnet ring (101) is installed on one end of the two tube bodies (81) away from the ball head tube (71), and the movable magnet ring (102) is fixedly installed on one side of the two hexagonal hole tubes (84) away from the tube body (81).

6. A medical assisted breathing device as claimed in claim 5, characterized in that: The sides of the fixed magnet ring (101) and the movable magnet ring (102) that are close to each other have opposite magnetic properties.

7. A medical assisted breathing device as claimed in claim 6, characterized in that: It also includes a finger rest (11), and a finger rest (11) is rotatably provided on one end of the two hexagonal hole tubes (84) away from the ball head tube (71).

8. A medical assisted breathing device as claimed in claim 7, characterized in that: The two finger rests (11) are both recessed on one side away from the hexagonal hole tube (84), and the recessed parts of the two finger rests (11) are both rough surfaces.

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