A two-way check valve with controllable check direction

Abstract

The present invention relates to the field of valve technology, and proposes a two-way check valve with controllable check direction for solving the problem that a check valve can only check in one direction, comprising a valve body and a valve stem, a spherical working chamber is arranged inside the valve body, a hemispherical valve plate is arranged inside the spherical working chamber, the diameter of the hemispherical valve plate is larger than the inner diameter of the water passage and smaller than the diameter of the spherical working chamber, a rubber sealing layer is covered on the outer surface of the hemispherical valve plate, a port of the rubber sealing layer is fixedly arranged on the port of the hemispherical valve plate, an expansion gap is formed between the rubber sealing layer and the outer surface of the hemispherical valve plate, which expands under the action of water pressure to enhance the sealing performance, a water opening connected to the expansion gap is opened on the end edge of the hemispherical valve plate, a telescopic rod is horizontally arranged between the hemispherical valve plate and the valve stem, the inner end of the telescopic rod is fixedly arranged on the valve stem, and the outer end is fixedly arranged on the middle part of the hemispherical valve plate.

Description

Technical Field

[0001] The invention relates to the technical field of valves, and in particular to a two-way check valve with controllable check direction. Background Art

[0002] A check valve is a valve that blocks the backflow of media. When the pressure at the input end is greater than that at the output end, the valve plate opens. When the pressure at the output end is greater than that at the input end, the valve plate closes to prevent the backflow of media, thus completing one-way transportation.

[0003] In some special bidirectional conveying pipelines, as the conveying direction changes, the check direction of the check valve also needs to change accordingly. However, most of the current check valves are one-way check valves, and the check direction cannot be adjusted, so they cannot be well used with bidirectional conveying pipelines.

[0004] This case arises to solve the above problems. Summary of the invention

[0005] Therefore, in view of the above-mentioned problem, the present invention proposes a two-way check valve with controllable check direction for solving the problem that the check valve can only check in one direction.

[0006] In order to solve the above technical problems, the solution adopted by the present invention is: a two-way check valve with controllable check direction, including a valve body, characterized in that: a spherical working chamber is arranged inside the valve body, and water passages connected to the spherical working chamber are respectively opened at both ends of the valve body, a valve stem is arranged in the spherical working chamber for vertical rotation, the upper end of the valve stem passes through the valve body, a hemispherical valve plate is arranged in the spherical working chamber, and the port in the water passage is tightly fitted with the top, the diameter of the hemispherical valve plate is larger than the inner diameter of the water passage and smaller than the diameter of the spherical working chamber, a rubber sealing layer is covered on the outer surface of the hemispherical valve plate, and the end of the rubber sealing layer A mouth is fixedly arranged on the port of the hemispherical valve plate, an expansion gap is formed between the rubber sealing layer and the outer surface of the hemispherical valve plate, which expands under the action of water pressure to enhance the sealing performance, a water opening connected to the expansion gap is opened on the end edge of the hemispherical valve plate, a telescopic rod is horizontally arranged between the hemispherical valve plate and the valve stem, the inner end of the telescopic rod is fixedly arranged on the valve stem, and the outer end is fixedly arranged on the middle part of the hemispherical valve plate, a sealing structure is arranged between the upper end of the valve stem and the valve body, and a driving member for driving the valve stem to drive the hemispherical valve plate to rotate is arranged on the top of the valve stem.

[0007] A further improvement is that when the hemispherical valve plate is separated from the two water passage positions at the same time, it can also be used as a normally open valve.

[0008] Further improvement is: a spherical limiting plate is provided on the hemispherical valve plate on the outer surface of the rubber sealing layer for reducing the expansion volume of the rubber sealing layer to increase the strength of the rubber sealing layer to seal the water passage; the spherical limiting plate does not cover the water passage opening; a mounting protrusion is integrally provided in the middle of the inner surface of the spherical limiting plate; both the rubber sealing layer and the hemispherical valve plate are provided with mounting openings for the mounting protrusion to pass through and fix the mounting protrusion; the mounting protrusion is fixedly connected to the outer end of the valve plate; the spherical limiting plate presses the rubber sealing layer against the hemispherical valve plate.

[0009] A further improvement is that a fixing ring is arranged on the port of the rubber sealing layer, a fixing ring groove for the fixing ring to be embedded in is opened on the end face of the port of the hemispherical valve plate, an annular pressure cover with a U-shaped cross-section is pressed on the end face of the hemispherical valve plate to press and fix the fixing ring and the rubber sealing layer, and a plurality of limiting connecting parts for limiting the annular pressure cover from detaching from the hemispherical valve plate are arranged on the inner side face of the annular pressure cover.

[0010] Further improvements are: a pressure regulating block for adjusting the opening pressure of the hemispherical valve plate is arranged on the inner end of the telescopic rod, a mounting sleeve for being sleeved on the outer surface of the valve stem is arranged on the inner end of the pressure regulating block, a fixing part for limiting the movement of the pressure regulating block is passed through the mounting sleeve, a threaded rod is arranged on the outer end of the pressure regulating block, and an internal threaded channel for being threadedly screwed with the threaded rod is opened on the inner end surface of the telescopic rod.

[0011] A further improvement is that a resistance elimination structure is provided between the valve stem and the hemispherical valve plate to eliminate the resistance of the valve body to the rotation of the hemispherical valve plate, and the resistance elimination structure includes:

[0012] At least two fixed circular rings are fixedly arranged on the inner end surface of the annular gland with the axis of the telescopic rod as the symmetrical center line, and the fixed circular rings are wound with traction ropes;

[0013] The valve stem comprises an outer tube and an inner rod, the upper and lower ends of the outer tube are respectively rotatably fixedly arranged on the valve body, the inner rod is rotatably fixedly arranged in the outer tube, the outer tube and the inner rod are respectively penetrated with a traction channel for the free end of the traction rope to pass through, a limiting block for limiting the traction rope from separating from the valve stem is fixedly arranged on the free end of the traction rope, the outer diameter of the limiting block is larger than the inner diameter of the traction channel, and a winding gap is formed between the outer tube and the inner rod for winding the traction rope to compress the telescopic rod so that a gap is generated between the hemispherical valve plate and the inner wall of the spherical working chamber to eliminate the rotation resistance;

[0014] The sealing structure is arranged between the outer tube and the valve body, the driving member is arranged at the top of the inner rod, and a plurality of first traction blocks and a plurality of second traction blocks are arranged between the outer tube and the inner rod above and / or below the traction rope, which are used to limit the angle of winding the traction rope of the inner rod and drive the outer tube to drive the hemispherical valve plate to rotate and reverse after reaching the maximum winding angle. The first traction block is fixedly arranged on the inner wall of the outer tube, and the second traction block is fixedly arranged on the outer wall of the inner rod. The first traction block and the second traction block interfere with each other, and a winding angle A for winding the traction rope is formed between the first traction block and the second traction block and the center of the inner rod to keep a gap between the hemispherical valve plate and the inner wall of the spherical working chamber.

[0015] A further improvement is that the sealing structure includes a plurality of sealing rings and a plurality of Y-shaped sealing rings, the inner wall of the upper port of the valve body or the outer wall of the valve stem is provided with a plurality of sealing grooves for embedding and installing sealing rings and Y-shaped sealing rings, and the sealing ring is located below the Y-shaped sealing ring.

[0016] A further improvement is that the driving member is a manual driving member or an electric driving member.

[0017] By adopting the above technical solution, the beneficial effects of the present invention are:

[0018] In the present case, a water passage is tightly closed by a hemispherical valve plate against the top, and under the action of the telescopic rod, when the pressure in the water passage is greater than the pressure in the other water passage and the elastic potential energy of the compression rod, the water pressure forces the telescopic rod to contract so that the hemispherical valve plate and the inner port of the water passage form a water outlet; when the pressure in the water passage at the other end is greater than the pressure in the water passage, the hemispherical valve plate presses against the top to seal the water passage under the water pressure and the elastic recovery of the telescopic rod, thereby achieving liquid blocking and check.

[0019] The valve stem drives the hemispherical valve plate to change direction to adjust the check direction of the check valve, so that the check valve can be used in a two-way delivery pipeline. The rubber sealing layer is arranged on the hemispherical valve plate instead of the inner ports of the two water passages, which is conducive to simplifying the check valve structure and the valve body.

[0020] The expansion gap formed by the rubber sealing layer is conducive to utilizing water pressure to improve the check seal effect.

[0021] A further beneficial effect is that the spherical limiting plate tightly arranged on the outer surface of the rubber sealing layer reduces the expandable volume of the rubber sealing layer, concentrates the water pressure to increase the strength of the rubber sealing layer to seal the water passage, and improves the sealing effect.

[0022] A further beneficial effect is that the rubber sealing layer port is fixedly mounted on the hemispherical valve plate port by the annular gland, thereby preventing the rubber sealing layer port from being separated from the hemispherical valve plate port and improving the sealing stability of the check valve.

[0023] A further beneficial effect is that the pressure regulating block arranged on the inner end of the telescopic rod can adjust the opening pressure of the hemispherical valve plate to adapt to the use of different pressure pipelines.

[0024] A further beneficial effect is that the valve stem can drive the hemispherical valve plate to rotate, but there is a large rotational resistance. The resistance elimination structure can effectively eliminate the rotational resistance of the valve body to the hemispherical valve plate, while avoiding wear of the rubber sealing layer and the spherical limiting plate.

[0025] The resistance elimination structure utilizes a double-layer valve stem and the retracting of the traction rope to force the telescopic rod to shrink smoothly, so that a gap is generated between the hemispherical valve plate and the inner wall of the valve body, eliminating the active resistance of the valve body to the valve plate, making it easier to drive the hemispherical valve plate to rotate and adjust the check reverse direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a front view structural schematic diagram of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0027] Figure 2 It is a schematic diagram of the internal structure of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0028] Figure 3 The figure is a schematic diagram of the internal front view structure of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0029] Figure 4 The figure is a schematic diagram of the internal front view structure of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0030] Figure 5 It is a structural schematic diagram of a valve stem in a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0031] Figure 6 The figure is a schematic diagram of the check state structure of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0032] Figure 7 It is a structural schematic diagram of an open state of a two-way check valve with controllable check direction according to an embodiment of the present invention.

[0033] Figure 8 yes Figure 2 A magnified view of the local structure at point A.

[0034] Fig. 9 yes Figure 2 A magnified view of the local structure at point B in the middle.

[0035] Fig.10 yes Figure 2 Enlarged view of the local structure at point C in the middle.

[0036] Fig.11 yes Figure 3 Enlarged view of the local structure at point D in the middle.

[0037] Fig.12 yes Figure 4 Enlarged view of the local structure at point E in the middle.

[0038] Fig.13 yes Figure 6 Enlarged view of the local structure at F in the middle.

[0039] Fig.14 yes Figure 7 Enlarged view of the local structure at G in the middle. DETAILED DESCRIPTION

[0040] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0041] refer to Figures 1 to 14 The embodiment of the present invention discloses a two-way check valve with controllable check direction, including a valve body 10, a spherical working chamber 11 is arranged inside the valve body 10, and water passages 12 communicating with the spherical working chamber 11 are respectively opened at both ends of the valve body 10, a valve stem 13 is arranged in the spherical working chamber 11 for vertical rotation, and the upper end of the valve stem 13 passes through the valve body 10, and a hemispherical valve plate 14 is arranged in the spherical working chamber 11 for sealing against a port in the water passage 12, the diameter of the hemispherical valve plate 14 is larger than the inner diameter of the water passage 12 and smaller than the diameter of the spherical working chamber 11, and a rubber sealing layer 15 is covered on the outer surface of the hemispherical valve plate 14, and the rubber sealing layer The port 15 is fixedly arranged on the port of the hemispherical valve plate 14, and an expansion gap 16 is formed between the rubber sealing layer 15 and the outer surface of the hemispherical valve plate 14, which expands under the action of water pressure to enhance the sealing performance. A water-passing opening 17 connected with the expansion gap 16 is opened on the end edge of the hemispherical valve plate 14, and a telescopic rod 18 is horizontally arranged between the hemispherical valve plate 14 and the valve stem 13. The inner end of the telescopic rod 18 is fixedly arranged on the valve stem 13, and the outer end is fixedly arranged on the middle part of the hemispherical valve plate 14. A sealing structure is arranged between the upper end of the valve stem 13 and the valve body 10, and a driving member for driving the valve stem 13 to drive the hemispherical valve plate 14 to rotate is arranged on the top of the valve stem 13.

[0042] A spherical limiting plate 19 is provided on the hemispherical valve plate 14 on the outer surface of the rubber sealing layer 15 for reducing the expansion volume of the rubber sealing layer 15 to increase the strength of the rubber sealing layer 15 to seal the water passage 12. The spherical limiting plate 19 does not cover the water passage opening. A mounting protrusion 20 is integrally provided in the middle of the inner surface of the spherical limiting plate 19. The rubber sealing layer 15 and the hemispherical valve plate 14 are both provided with mounting openings for the mounting protrusion 20 to pass through and fix the mounting protrusion 20. The mounting protrusion is fixedly connected to the outer end of the valve plate by threads. The spherical limiting plate 19 presses the rubber sealing layer 15 against the hemispherical valve plate 14.

[0043] A fixing ring 21 is arranged on the port of the rubber sealing layer 15, a fixing ring groove 22 for embedding the fixing ring 21 is opened on the end face of the port of the hemispherical valve plate 14, an annular pressure cover 23 with a U-shaped cross-section is pressed on the end face of the hemispherical valve plate 14, and the fixing ring 21 and the rubber sealing layer 15 are pressed and fixed thereto, and a plurality of limiting connectors 24 for limiting the annular pressure cover 23 from detaching from the hemispherical valve plate 14 are arranged on the inner side face of the annular pressure cover 23, and the limiting connectors 24 are bolts, which pass through the inner side face of the annular pressure cover 23 and are threadedly fixedly connected to the hemispherical valve plate 14.

[0044] A pressure regulating block 25 for adjusting the opening pressure of the hemispherical valve plate 14 is arranged on the inner end of the telescopic rod 18, and a mounting sleeve 26 for being sleeved on the outer surface of the valve stem 13 is arranged on the inner end of the pressure regulating block 25. A fixing member 27 for limiting the movement of the pressure regulating block 25 is passed through the mounting sleeve 26, and the fixing member 27 is a bolt, and the bolt passes through the mounting sleeve and is threadedly fixed on the valve stem 13. A threaded rod 28 is integrally arranged on the outer end of the pressure regulating block 25, and an internal threaded channel 29 threadedly connected to the threaded rod is provided on the inner end surface of the telescopic rod 18. The preload elastic force of the spring in the telescopic rod 18 is adjusted by adjusting the position of the threaded rod 28 screwed in the threaded channel 29 to adjust the opening pressure of the hemispherical valve plate 14.

[0045] A resistance elimination structure is provided between the valve stem 13 and the hemispherical valve plate 14, and is used to eliminate the resistance of the valve body 10 to the rotation of the hemispherical valve plate 14. The resistance elimination structure includes:

[0046] Four fixed rings 30 are integrally fixedly arranged on the inner end surface of the annular gland 23 with the axis of the telescopic rod 18 as the symmetrical center line, and a traction rope 31 is wound around the fixed ring 30;

[0047] The valve stem 13 includes an outer tube 32 and an inner rod 33. The upper and lower ends of the outer tube 32 are rotatably fixedly arranged on the valve body 10, and the inner rod 33 is rotatably fixedly arranged in the outer tube 32. The outer tube 32 and the inner rod 33 are respectively penetrated with a traction channel 34 for the free end of the traction rope 31 to pass through. A limiting block 35 for limiting the traction rope 31 from separating from the valve stem 13 is fixedly arranged on the free end of the traction rope 31. The traction rope 31 is fixedly arranged around the limiting block 35. The outer diameter of the limiting block 35 is larger than the inner diameter of the traction channel 34. A winding gap 36 is formed between the outer tube 32 and the inner rod 33 for winding the traction rope 31 to compress the telescopic rod 18 so that a gap is generated between the hemispherical valve plate 14 and the inner wall of the spherical working chamber 11 to eliminate the rotation resistance.

[0048] The sealing structure is arranged between the outer tube 32 and the valve body 10, and the driving member is arranged at the top of the inner rod 33. Two first traction blocks 37 and four second traction blocks 38 are arranged between the outer tube 32 and the inner rod 33 above and / or below the traction rope 31, which are used to limit the angle of the inner rod 33 winding the traction rope 31 and drive the outer tube 32 to drive the hemispherical valve plate 14 to rotate and reverse after reaching the maximum winding angle. The first traction block 37 is integrally fixed on the inner wall of the outer tube 32, and the second traction block 38 is integrally fixed on the outer wall of the inner rod 33. The first traction block 37 and the second traction block 38 interfere with each other, and a winding angle A for winding the traction rope 31 is formed between the first traction block 37 and the second traction block 38 and the center of the inner rod 33 to keep a gap between the hemispherical valve plate 14 and the inner wall of the spherical working chamber 11. The free end of the first traction block 37 is in contact with the outer surface of the inner rod 33 , and the free end of the second traction block 38 is in contact with the inner surface of the outer tube 32 , so as to increase the rotation stability between the outer tube 32 and the inner rod 33 of the valve stem 13 .

[0049] The sealing structure includes two sealing rings 39 and three Y-shaped sealing rings 40. The inner wall of the upper port of the valve body 10 or the outer wall of the valve stem 13 is provided with five sealing grooves for embedding and installing the sealing rings 39 and Y-shaped sealing rings 40. The sealing rings are located below the Y-shaped sealing rings. The driving member 41 is a manual driving member or an electric driving member, and the installation and use between the valve and the driving member 41 is a conventional setting.

[0050] A reversing method for a two-way check valve with controllable check direction: the inner rod 33 of the valve stem 13 is driven to rotate by a driving member, the inner rod 33 first reels the traction rope 31 within an angle A, the traction rope 31 drives the hemispherical valve plate 14 to move toward the valve stem 13, forcing the telescopic rod 18 to contract, so that a rotation gap is generated between the hemispherical valve plate 14 and the inner wall of the valve body 10 and rotates, after the inner rod 33 rotates by an angle A, the first traction block contacts and interferes with the second traction block, the inner rod 33 continues to rotate 180 degrees, and drives the outer tube 32 of the valve stem 13 to rotate through the second traction block, and the outer tube 32 drives the hemispherical valve plate 14 to rotate 180 degrees to perform reversal. After the reversal is completed, the driving member rotates in the opposite direction by an angle A to release the retracted traction rope 31, release the telescopic rod 18, eliminate the gap between the hemispherical valve plate 14 and the inner wall of the valve body 10, and make the hemispherical valve plate 14 abut against and seal a water passage 12.

[0051] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention shall be defined by the attached claims and their equivalents.

Claims

1. A two-way check valve with controllable check direction, comprising a valve body, characterized in that: A spherical working chamber is arranged inside the valve body, and water passages communicating with the spherical working chamber are respectively opened at both ends of the valve body. A valve stem is arranged in the spherical working chamber for vertical rotation, and the upper end of the valve stem passes through the valve body. A hemispherical valve plate for abutting against and tightly fitting a port in the water passage is arranged in the spherical working chamber, and the diameter of the hemispherical valve plate is larger than the inner diameter of the water passage and smaller than the diameter of the spherical working chamber. A rubber sealing layer is covered on the outer surface of the hemispherical valve plate, and the port of the rubber sealing layer is fixedly arranged on the hemispherical valve plate. An expansion gap is formed between the rubber sealing layer and the outer surface of the hemispherical valve plate under the action of water pressure to enhance the sealing performance. A water-passing opening connected to the expansion gap is provided on the end edge of the hemispherical valve plate. A telescopic rod is horizontally arranged between the hemispherical valve plate and the valve stem. The inner end of the telescopic rod is fixedly arranged on the valve stem, and the outer end is fixedly arranged on the middle part of the hemispherical valve plate. A sealing structure is arranged between the upper end of the valve stem and the valve body. A driving member for driving the valve stem to drive the hemispherical valve plate to rotate is arranged on the top of the valve stem. A spherical limiting plate is provided on the outer surface of the rubber sealing layer on the hemispherical valve plate for reducing the expansion volume of the rubber sealing layer so as to increase the strength of the rubber sealing layer to seal the water passage. The spherical limiting plate does not cover the water passage opening. A mounting protrusion is integrally provided in the middle of the inner surface of the spherical limiting plate. Both the rubber sealing layer and the hemispherical valve plate are provided with mounting openings for the mounting protrusion to pass through and fix the mounting protrusion. The mounting protrusion is fixedly connected to the outer end of the valve plate, and the spherical limiting plate presses the rubber sealing layer against the hemispherical valve plate.

2. A two-way check valve with controllable check direction according to claim 1, characterized in that: A fixing ring is arranged on the port of the rubber sealing layer, a fixing ring groove for the fixing ring to be embedded in is opened on the end face of the port of the hemispherical valve plate, an annular pressure cover with a U-shaped cross-section is pressed on the end face of the hemispherical valve plate to press and fix the fixing ring and the rubber sealing layer, and a plurality of limiting connectors for limiting the annular pressure cover from detaching from the hemispherical valve plate are arranged on the inner side face of the annular pressure cover.

3. A two-way check valve with controllable check direction according to claim 1, characterized in that: A pressure regulating block for adjusting the opening pressure of the hemispherical valve plate is arranged on the inner end of the telescopic rod, a mounting sleeve for being sleeved on the outer surface of the valve stem is arranged on the inner end of the pressure regulating block, a fixing piece for limiting the movement of the pressure regulating block is passed through the mounting sleeve, a threaded rod is arranged on the outer end of the pressure regulating block, and an internal threaded channel which is threadedly screwed with the threaded rod is opened on the inner end surface of the telescopic rod.

4. A two-way check valve with controllable check direction according to claim 2, characterized in that: A resistance elimination structure is provided between the valve stem and the hemispherical valve plate to eliminate the resistance of the valve body to the rotation of the hemispherical valve plate, and the resistance elimination structure includes: At least two fixed circular rings are fixedly arranged on the inner end surface of the annular gland with the axis of the telescopic rod as the symmetrical center line, and the fixed circular rings are wound with traction ropes; The valve stem comprises an outer tube and an inner rod, the upper and lower ends of the outer tube are respectively rotatably fixedly arranged on the valve body, the inner rod is rotatably fixedly arranged in the outer tube, the outer tube and the inner rod are respectively penetrated with a traction channel for the free end of the traction rope to pass through, a limiting block for limiting the traction rope from separating from the valve stem is fixedly arranged on the free end of the traction rope, the outer diameter of the limiting block is larger than the inner diameter of the traction channel, and a winding gap is formed between the outer tube and the inner rod for winding the traction rope to compress the telescopic rod so that a gap is generated between the hemispherical valve plate and the inner wall of the spherical working chamber to eliminate the rotation resistance; The sealing structure is arranged between the outer tube and the valve body, the driving member is arranged at the top of the inner rod, and a plurality of first traction blocks and a plurality of second traction blocks are arranged between the outer tube and the inner rod above and / or below the traction rope, which are used to limit the angle of winding the traction rope of the inner rod and drive the outer tube to drive the hemispherical valve plate to rotate and reverse after reaching the maximum winding angle. The first traction block is fixedly arranged on the inner wall of the outer tube, and the second traction block is fixedly arranged on the outer wall of the inner rod. The first traction block and the second traction block interfere with each other, and a winding angle A for winding the traction rope is formed between the first traction block and the second traction block and the center of the inner rod to keep a gap between the hemispherical valve plate and the inner wall of the spherical working chamber.

5. A two-way check valve with controllable check direction according to claim 1 or 4, characterized in that: The sealing structure includes a plurality of sealing rings and a plurality of Y-shaped sealing rings. The inner wall of the upper port of the valve body or the outer wall of the valve stem is provided with a plurality of sealing grooves for embedding and installing sealing rings and Y-shaped sealing rings. The sealing ring is located below the Y-shaped sealing ring.

6. A two-way check valve with controllable check direction according to claim 4, characterized in that: The driving member is a manual driving member or an electric driving member.

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