Manual gas cutter

Abstract

To provide a manual gas cutter that improves workability.SOLUTION: A manual gas cutter includes a body having a flow passage 11a through which oxygen flows, and a cutting oxygen valve 50 capable of closing or opening the flow passage 11a. The cutting oxygen valve 50 includes a cylinder 51 which is communicated with the flow passage 11a, a valve 54 which is inserted into the cylinder 51 so as to advance or retreat and has a valve close part 54c capable of closing the flow passage 11a, and an operation part 57 which is connected with the valve 54 and is rotatable with respect to the valve 54 around a rotation axis O2 extending in a direction different from an advancing and retreating direction B of the valve 54. The operation part 57 rotates around the rotation axis O2, and thereby, the valve 54 advances and retreats in the advancing and retreating direction B and can close or open the flow passage 11a.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a manual gas cutter. [Background technology]

[0002] Conventionally, there are gas cutters that cut a cutting object such as a steel plate by supplying fuel gas and oxygen. The gas cutter heats the cutting portion of the cutting object by emitting a flame from a nozzle at the tip of the gas cutter, emitting oxygen to the heated cutting portion to burn it, and blowing away the burnt cutting portion with the oxygen to cut the cutting object. Gas cutters include manual gas cutters that an operator holds in his / her hand to perform cutting work (for example, Patent Document 1).

[0003] Manual gas cutters are equipped with a cutting oxygen valve that adjusts the amount of oxygen (cutting oxygen) released to cut the object. When an operator uses a manual gas cutter to cut steel or other materials, the operator may start cutting from a location other than the end of the steel plate. In this case, a location on the steel plate is first heated with a preheating flame. When the steel plate becomes red hot, the cutting oxygen valve is fully opened, a hole is made in the steel plate (piercing), and then cutting begins.

[0004] Conventionally, cutting oxygen valves installed in manual gas cutters include handle (knob) type and lever type cutting oxygen valves. With a handle type cutting oxygen valve, the flow rate of cutting oxygen can be adjusted by rotating the handle (knob). When the operation of the handle is stopped, the flow rate of cutting oxygen is maintained. With a lever type cutting oxygen valve, the flow rate of cutting oxygen can be fully opened by squeezing the lever, and the flow of cutting oxygen can be closed by releasing the lever. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Registered Utility Model No. 2544700 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when using a handle-type cutting oxygen valve, the operator must hold the main body of the manual gas cutter with one hand and rotate the handle of the cutting oxygen valve with the other hand, which may cause the cutting oxygen stream emitted from the nozzle to move away from the piercing point. This makes it difficult to fix the position of the manual gas cutter, which may result in poor workability. In addition, when using a lever-type cutting oxygen valve, the operator must continue to hold the lever while cutting, which may tire the operator's hands and make it difficult to work for long periods of time, which may result in poor workability.

[0007] In view of the above circumstances, an object of the present invention is to provide a manual gas cutter with improved operability. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention proposes the following means. The manual gas cutter of the present invention comprises a main body portion in which a flow path through which oxygen flows, and a cutting oxygen valve capable of blocking or opening the flow path, the cutting oxygen valve comprising a cylinder portion connected to the flow path, a valve that can be inserted into the cylinder portion and moved back and forth and has a valve blocking portion that can block the flow path, and an operating unit connected to the valve and rotatable relative to the valve around a rotation axis that extends in a direction different from the advancement and retreat direction of the valve, and the valve can be advanced and retreated in the advancement and retreat direction by rotating the operating unit around the rotation axis as the rotation center, thereby blocking or opening the flow path. Effect of the Invention

[0009] According to the manual gas cutter of the present invention, it is possible to provide a manual gas cutter with improved operability. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of the configuration of a manual gas cutter according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram showing an example of the external shape of the manual gas cutter. [Diagram 3] FIG. 4 is a cross-sectional view showing the cutting oxygen valve of the manual gas cutter when an operating portion of the cutting oxygen valve is located at a first position. [Figure 4] FIG. 4 is a cross-sectional view showing the cut-off oxygen valve when the operating unit is located at a second position. [Diagram 5] FIG. 4 is a cross-sectional view showing the cut-off oxygen valve when the operating unit is located in a third position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a diagram showing an example of the configuration of a manual gas cutter 1 according to this embodiment. Fig. 2 is a diagram showing an example of the outer shape of the manual gas cutter 1.

[0012] The manual gas cutter 1 comprises a main body 10, an oxygen supply port 20, a fuel gas supply port 30, a torch 40, a cutting oxygen valve 50, a preheating oxygen valve 60, and a fuel gas valve 70.

[0013] The manual gas cutting tool 1 is a gas cutting tool in which oxygen supplied from an oxygen supply port 20 and fuel gas supplied from a fuel gas supply port 30 are released from a torch 40 via a flow path (conduit) provided inside a main body 10.

[0014] An operator can ignite the gas released from the manual gas cutting tool 1 with a lighter or the like, thereby causing a flame P to be emitted from the torch 40. The operator applies the flame P released from the manual gas cutting tool 1 to a part to be cut of the workpiece W to heat the part to be cut, releases oxygen onto the heated part to burn it, and blows away the burnt part to be cut with the oxygen, thereby cutting the workpiece W.

[0015] 1 and 2, in the manual gas cutter 1, the horizontal direction in which mainly oxygen and fuel gas flow is defined as "flow direction A," the side on which oxygen supply port 20 and fuel gas supply port 30 are provided is defined as the "upstream side A1" in flow direction A, and the side opposite upstream side A1 is defined as the "downstream side A2" in flow direction A. Additionally, the vertical direction in the manual gas cutter 1 is defined as "upper-lower direction B," the vertical upward direction is defined as "upper side B1" in vertical direction B, and the vertical downward direction is defined as "lower side B2" in vertical direction B. Additionally, the direction perpendicular to flow direction A and vertical direction B is defined as "width direction C."

[0016] In this embodiment, an example will be described in which the flame P is emitted from the manual gas cutter 1 in a vertical direction toward the workpiece W, but the direction in which the manual gas cutter 1 is used is not limited to this, and for example, the manual gas cutter 1 may be used to emit the flame P in a horizontal direction. In that case, in the manual gas cutter 1, the oxygen and fuel gas may flow mainly in a vertical direction.

[0017] The main body 10 comprises a grip portion 11 , a cutting oxygen tube 12 , and a mixing tube 13 .

[0018] 1, in a manual gas cutter 1, oxygen supplied from an oxygen supply port 20 branches into oxygen that passes through a cutting oxygen valve 50 (cutting oxygen) and oxygen that passes through a preheating oxygen valve 60 (preheated oxygen). Fuel gas supplied from a fuel gas supply port 30 passes through a fuel gas valve 70, and then merges with and is mixed with the preheated oxygen to form a mixed gas.

[0019] The grip 11 is a gripping portion of the main body 10 that is primarily gripped by an operator with his or her hand. Inside the grip 11, a flow path through which oxygen supplied from the oxygen supply port 20 flows and a flow path through which fuel gas supplied from the fuel gas supply port 30 flows are formed.

[0020] The cutting oxygen line 12 is a conduit through which cutting oxygen flows via a cutting oxygen valve 50 . The mixing tube 13 is a conduit through which a mixed gas of preheated oxygen and fuel gas flows.

[0021] The oxygen supply port 20 is provided on the upstream side A1 of the main body 10, and is an opening that can supply oxygen from the outside to the inside of the manual gas cutter 1. For example, the oxygen supply port 20 is connected to an oxygen cylinder (not shown) filled with oxygen by a hose (not shown) via a pressure regulator. Oxygen is supplied from the oxygen cylinder to the oxygen supply port 20 via the pressure regulator and the hose, and oxygen flows into the inside of the manual gas cutter 1 from the oxygen supply port 20.

[0022] Oxygen that flows into the manual gas cutter 1 from the oxygen supply port 20 flows through a flow path formed in the main body 10 to the cutting oxygen valve 50 and the preheating oxygen valve 60 .

[0023] The fuel gas supply port 30 is provided on the upstream side A1 of the main body 10, and is an opening capable of supplying fuel gas from the outside into the inside of the manual gas cutter 1. For example, the fuel gas supply port 30 is connected to a fuel gas cylinder (not shown) filled with fuel gas by a hose (not shown) via a pressure regulator. Fuel gas is supplied from the fuel gas cylinder to the fuel gas supply port 30 via the pressure regulator and the hose, and the fuel gas flows into the inside of the manual gas cutter 1 from the fuel gas supply port 30.

[0024] The fuel gas that flows into the manual gas cutter 1 from the fuel gas supply port 30 flows to the fuel gas valve 70 via a flow path formed in the main body 10 .

[0025] The torch 40 is provided on the downstream side A2 of the main body 10, and is a portion into which the cutting oxygen via the cutting oxygen pipe 12 and the mixed gas via the mixing pipe 13 flow. The tip of the torch 40 is provided with a nozzle 41 capable of releasing oxygen and the mixed gas from a tip 41a. As shown in Fig. 1, inside the nozzle 41, an oxygen release flow passage 42 through which the oxygen flowing in from the main body 10 flows, and a gas release flow passage 43 through which the mixed gas flowing in from the main body 10 flows are formed.

[0026] The cutting oxygen valve 50 is a valve provided in the main body 10 and capable of changing the flow rate of oxygen flowing from the oxygen supply port 20 to the oxygen release flow passage 42. By operating the cutting oxygen valve 50, the operator can change the amount of oxygen (cutting oxygen) released from the tip 41a of the nozzle 41. The cutting oxygen valve 50 will be described in detail later.

[0027] The preheating oxygen valve 60 is a valve provided in the main body 10 and capable of changing the flow rate of oxygen (preheated oxygen) flowing from the oxygen supply port 20 to the gas release flow path 43. By operating the preheating oxygen valve 60, an operator can change the amount of preheated oxygen released from the tip 41a of the nozzle 41 as a mixed gas mixed with fuel gas. By operating the preheating oxygen valve 60, an operator can change the mixture ratio of preheated oxygen and fuel gas.

[0028] The fuel gas valve 70 is a valve provided in the main body 10 and capable of changing the flow rate of the fuel gas flowing from the fuel gas supply port 30 to the gas discharge flow passage 43. By operating the fuel gas valve 70, an operator can change the amount of fuel gas discharged from the tip 41a of the nozzle 41 as a mixed gas mixed with preheated oxygen. By operating the fuel gas valve 70, an operator can change the mixture ratio of preheated oxygen and fuel gas. The preheating oxygen valve 60 and the fuel gas valve 70 may employ known valve structures used in conventional manual gas cutters.

[0029] An operator can hold the grip 11 with one hand and operate the cutting oxygen valve 50, the preheating oxygen valve 60, and the fuel gas valve 70 with the other hand to change the amount of cutting oxygen and mixed gas released from the tip 41a of the nozzle 41. The operator may operate the cutting oxygen valve 50, the preheating oxygen valve 60, and the fuel gas valve 70 with the hand holding the grip 11.

[0030] Next, the configuration of the cutting oxygen valve 50 will be described. Fig. 3 is a cross-sectional view showing the cutting oxygen valve 50. The cutting oxygen valve 50 shown in Fig. 3 is a cutting oxygen valve 50 in which an operating part 57, which will be described later, is located at a first position P1.

[0031] The cutting oxygen valve 50 includes a cylinder portion 51 , a valve 54 , a biasing member 55 , an O-ring 56 , an operating portion 57 , and a shaft pin 58 .

[0032] The cylinder portion 51 includes a nut portion 52 and a packing 53. The cylinder portion 51 is provided in the main body portion 10. In the main body portion 10, in the vicinity of the cutting oxygen valve 50, a first flow path 11a, a second flow path 11b, and a third flow path 11c, which are flow paths through which oxygen flows, are formed.

[0033] A cylinder flow passage 51a communicating with the first flow passage 11a is formed in the cylinder portion 51. The first flow passage 11a and the cylinder flow passage 51a communicate with each other through a communication hole 51b provided in a lower portion B2 of the cylinder flow passage 51a.

[0034] Oxygen that flows into the main body 10 from the oxygen supply port 20 flows through the first flow path 11a to the vicinity of the cutting oxygen valve 50. In the vicinity of the cutting oxygen valve 50, the oxygen flowing through the first flow path 11a branches into a cylinder flow path 51a and a second flow path 11b.

[0035] As shown in Fig. 3, the second flow passage 11b is connected to the downstream side A2 of the first flow passage 11a and extends downward B2. The oxygen that flows from the first flow passage 11a into the second flow passage 11b flows through the second flow passage 11b to the preheating oxygen valve 60. When the preheating oxygen valve 60 is open, the oxygen flowing through the second flow passage 11b merges with the fuel gas that has passed through the fuel gas valve 70 to form a mixed gas. As described above, the mixed gas flows into the gas discharge flow passage 43 of the burner nozzle 41 and is discharged from the tip 41a of the burner nozzle 41.

[0036] In addition, the cylinder flow path 51a communicates with the third flow path 11c on the downstream side A2. Therefore, the oxygen that flows from the first flow path 11a into the cylinder flow path 51a flows from the cylinder flow path 51a into the third flow path 11c. The oxygen (cutting oxygen) that flows into the third flow path 11c passes through the inside of the cutting oxygen pipe 12 and flows into the oxygen release flow path 42 of the nozzle 41, and is released from the tip 41a of the nozzle 41. In addition, the cylinder flow path 51a opens upward B1.

[0037] The nut portion 52 is provided above the cylinder flow passage 51a on the side B1. The nut portion 52 is, for example, a gland nut, and is connected to a groove provided in the main body portion 10 by being screwed thereto.

[0038] The packing 53 is provided below B2 the nut portion 52. The packing 53 is a packing member that fills a gap in the vertical direction B between the nut portion 52 and a portion of the body portion 10 that is screwed with the nut portion 52.

[0039] The valve 54 is a cylindrical member centered on an axis O1 extending in the vertical direction B, and is inserted into the cylinder flow path 51a of the cylinder portion 51 in the vertical direction B. Here, the cylindrical shape does not necessarily mean that the valve 54 is a cylinder in the strict sense. The valve 54 includes a valve core rod 54a, a valve large diameter portion 54b, and a valve closing portion 54c.

[0040] As shown in FIG. 3, the valve core rod 54a is inserted in the up-down direction B through openings provided in the nut portion 52 and the packing 53.

[0041] The valve large diameter portion 54b is provided below the valve core rod 54a at B2 and has a larger diameter than the valve core rod 54a. The diameter of the valve large diameter portion 54b is slightly smaller than the diameter of the cylinder flow path 51a.

[0042] The valve closing portion 54c is provided below the valve large diameter portion 54b at B2, and forms the tip of the valve 54 at the lower B2. As shown in Fig. 3, the valve closing portion 54c has a conical shape that narrows toward the lower B2. Here, the conical shape does not necessarily have to be a cone in the strict sense.

[0043] 3 is capable of closing the communication hole 51b by contacting the edge of the communication hole 51b provided in the lower B2 of the cylinder flow path 51a. When the communication hole 51b is closed by the valve closing part 54c, the oxygen flowing through the first flow path 11a does not flow from the first flow path 11a into the cylinder flow path 51a.

[0044] 3, the biasing member 55 is a spring member through which the valve core rod 54a is inserted, and is disposed between the packing 53 and the valve large diameter portion 54b in the vertical direction B. The communication hole 51b of the cylinder flow path 51a is blocked by the valve blocking portion 54c of the valve 54 which is biased downward B2 by the biasing member 55.

[0045] O-ring 56 is an annular O-ring made of rubber or the like, and is provided in a recess formed in the outer circumferential surface of valve large diameter portion 54b as shown in Fig. 3. O-ring 56 is sandwiched between valve large diameter portion 54b and cylinder flow path 51a in the horizontal direction (flow direction A and width direction C), and is in contact with valve large diameter portion 54b and cylinder flow path 51a.

[0046] Since the O-ring 56 fills the gap between the valve large diameter portion 54b and the cylinder flow passage 51a, the oxygen that flows from the first flow passage 11a into the cylinder flow passage 51a does not leak from the opening at the upper B1 of the cylinder flow passage 51a.

[0047] The operating portion 57 is provided above the nut portion 52, at a position B1. The shaft pin 58 is a rod-shaped member extending in the width direction C, and is an axial member that rotatably connects the operation part 57 and the valve core rod 54a. The operation part 57 is provided rotatably with respect to the valve 54 via the shaft pin 58, with a rotation axis O2 extending in the width direction C as the rotation center.

[0048] The operation unit 57 includes an operation unit main body 571 and a trigger 572 . The operating portion main body 571 is a main body portion of the operating portion 57 that is connected to the valve core rod 54 a by the shaft pin 58 .

[0049] The trigger 572 is a protruding part that protrudes from the operating part main body 571, and protrudes in a direction away from the rotation axis O2. The trigger 572 is a gripping part that can be gripped by hand when an operator operates the cutting oxygen valve 50.

[0050] 3, the direction in which the operating unit 57 rotates clockwise around the rotation axis O2 is referred to as a first rotation direction R1, and the direction in which the operating unit 57 rotates counterclockwise opposite to the first rotation direction R1 is referred to as a second rotation direction R2. In addition, as shown in FIG. 3, the position of the operating unit 57 when the valve closing unit 54c closes the communication hole 51b of the cylinder flow path 51a to close the flow path through which oxygen flows is referred to as a first position P1.

[0051] Fig. 4 is a cross-sectional view showing the cutting oxygen valve 50. The cutting oxygen valve 50 shown in Fig. 4 is the cutting oxygen valve 50 in which the operating part 57 located at the first position P1 has been rotated in the first rotation direction R1.

[0052] In the operation unit 57 located at the first position P1 shown in FIG. 3, the first side portion 571a of the operation unit body 571 faces the upper B1 surface (cylinder upper end portion) 52s of the nut portion 52 in the cylinder portion 51 with a small gap therebetween. Here, the cylinder upper end portion 52s indicates the end portion (upper end) of the upper B1 of the cylinder portion 51, and indicates the upper B1 surface of the nut portion 52 in the example shown in FIG. 3. In the operation unit body 571, the first side portion 571a forms a surface facing the cylinder portion 51 side when the operation unit 57 is located at the first position P1. In the example shown in FIG. 3, the trigger 572 extends from the operation unit body 571 to the upper B1, and the first side portion 571a forms the lower B2 surface of the operation unit body 571. At this time, the distance from the rotation axis O2 of the operation unit 57 to the cylinder upper end portion 52s is referred to as a first distance (distance) L1.

[0053] 4, a second side portion 571b of an operating portion main body 571 is in contact with the cylinder upper end portion 52s. The second side portion 571b forms a surface facing the upstream side A1 in the operating portion 57 located at the first position P1 shown in FIG.

[0054] The second side portion 571b moves to a position B2 below the operating portion 57 as the operating portion 57 rotates in the first rotation direction R1, and comes into contact with the cylinder upper end portion 52s facing each other in the vertical direction B. At this time, the distance from the rotation axis O2 of the operating portion 57 to the cylinder upper end portion 52s is referred to as a second distance (distance) L2. The second distance L2 is greater than the first distance L1.

[0055] Since the first distance L1 is smaller than the second distance L2, when the operating part 57 rotates from the first position P1 to the second position P2, the rotation axis O2 of the operating part 57 moves upward B1. That is, the pivot pin 58 moves upward B1.

[0056] Here, the valve 54 is provided so as to be movable back and forth in the vertical direction B. Therefore, when the pivot pin 58 connecting the operation part 57 and the valve 54 moves upward B1, the valve 54 moves upward B1.

[0057] When the valve 54 moves upward B1, the valve closing portion 54c moves upward B1 away from the communication hole 51b of the cylinder flow path 51a, and the communication hole 51b is opened, as shown in Fig. 4. At this time, the oxygen flow path formed by the first flow path 11a and the cylinder flow path 51a is opened, and oxygen can flow from the first flow path 11a to the cylinder flow path 51a.

[0058] Here, the position of the operating part 57 when the valve closing part 54c does not block the communication hole 51b of the cylinder flow path 51a and the flow path through which oxygen flows is referred to as the second position P2. The operating part 57 of the cutting oxygen valve 50 shown in FIG. 4 is located in the second position P2.

[0059] When the operating part 57 is in the first position P1 and the valve 54 is closing the oxygen flow path, the operator rotates the operating part 57 in the first rotation direction R1 about the rotation axis O2 as the rotation center to set it to the second position P2. By setting the operating part 57 to the second position P2, the valve 54 moves upward B1 and the oxygen flow path that was closed by the valve 54 is opened. When the flow path is opened, oxygen that has flowed into the manual gas cutter 1 from the oxygen supply port 20 flows in this order through the first flow path 11a, the cylinder flow path 51a, and the third flow path 11c, and is released from the tip 41a of the nozzle 41.

[0060] In the example shown in Fig. 3, the first distance L1 is the distance in the vertical direction B from the rotation axis O2 to the cylinder upper end 52s when the operating unit 57 is located at the first position P1. In the example shown in Fig. 4, the second distance L2 is the distance in the vertical direction B from the rotation axis O2 to the cylinder upper end 52s when the operating unit 57 is located at the second position P2. The first distance L1 and the second distance L2 only need to indicate the distance from the rotation axis O2 to the cylinder upper end 52s, and are not limited to the distance in the vertical direction B.

[0061] In addition, in operation unit main body 571 of operation unit 57, first side portion 571a and second side portion 571b are connected by third side portion 571c. Third side portion 571c is an arc-shaped surface (R surface) in the cross-sectional views shown in Figures 3 and 4. Here, the arc shape does not have to be strictly an arc shape.

[0062] When the valve 54, which is movable in the vertical direction B, moves upward B1, it is urged downward B2 by the urging member 55. When the operation unit 57 rotates from the first position P1 to the second position P2, it is urged downward B2 by the urging member 55 via the pivot pin 58 and the valve 54.

[0063] Therefore, when the operating part 57 rotates from the first position P1 to the second position P2, the operating part 57 rotates from the end of the upstream side A1 of the first side part 571a to the second side part 571b while contacting the cylinder upper end part 52s. Specifically, the operating part main body 571 rotating from the first position P1 to the second position P2 rotates in the first rotation direction R1 while contacting the cylinder upper end part 52s in the order of the end of the upstream side A1 of the first side part 571a, the third side part 571c, and the second side part 571b. At this time, since the third side part 571c has an arc shape in a cross section parallel to the up-down direction B, the operating part 57 can rotate smoothly in the first rotation direction R1. Therefore, the operator can rotate the operating part 57 from the first position P1 to the second position P2 without requiring a large force. In addition, the operator can easily rotate the operating part 57 by gripping the trigger 572.

[0064] The operating unit 57 is held in the first position P1 or the second position P2 because it is pulled downward B2 by the valve closing unit 54c biased by the biasing member 55. Therefore, when an operator rotates the operating unit 57 from the first position P1 to the second position P2 by operating the operating unit 57 with his / her hand and then releases the operating unit 57, the operating unit 57 is held in the second position P2.

[0065] Fig. 5 is a cross-sectional view showing the cutting oxygen valve 50. The cutting oxygen valve 50 shown in Fig. 5 is the cutting oxygen valve 50 in which the operating part 57 located at the first position P1 has been rotated in the second rotation direction R2.

[0066] 3, the operator rotates the operation unit 57 in the second rotation direction R2 by pushing the trigger 572 toward the downstream side A2. At this time, the operation unit 57 rotates in the second rotation direction R2 with respect to the valve 54 around the rotation axis O2 as the rotation center, and further rotates around the end of the first side portion 571a on the downstream side A2 as the rotation center. When the trigger 572 is pushed toward the downstream side A2, the trigger 572 tilts toward the downstream side A2 with the end of the first side portion 571a on the downstream side A2 in contact with the cylinder upper end portion 52s.

[0067] 5, the pivot pin 58 and the valve 54 move upward B1, and the valve closing portion 54c moves away from the communication hole 51b of the cylinder flow path 51a, opening the communication hole 51b and allowing oxygen to flow from the first flow path 11a into the cylinder flow path 51a. In other words, the oxygen flow path is opened.

[0068] The position of the operating part 57 in a state where the operating part 57 located at the first position P1 rotates in the second rotation direction R2 and the end of the upstream side A1 of the first side part 571a is separated from the cylinder upper end 52s and floats is referred to as a third position P3. The operating part 57 of the cutting oxygen valve 50 shown in FIG. 5 is located at the third position P3. When the operating part 57 is located at the third position P3, the oxygen flow path is open. When the operating part 57 is located at the third position P3, the distance (third distance) L3 from the rotation axis O2 to the cylinder upper end 52s is greater than the first distance L1.

[0069] When the operating part 57 is positioned at the third position P3, the end of the upstream side A1 of the first side portion 571a is floating above the upper end portion 52s of the cylinder compared to when the operating part 57 is positioned at the first position P1. Therefore, when the operator releases the operating part 57, the valve 54, which is biased by the biasing member 55, is pulled downward B2 and returns to the first position P1.

[0070] When the operating part 57 is located at the first position P1 or the second position P2, the operating part 57 is held at that position (the first position P1 or the second position P2) even if the operator releases the operating part 57. In addition, since the first side portion 571a and the second side portion 571b are connected by the third side portion 571c, the operator can rotate the operating part 57 in the first rotation direction R1 to rotate it from the first position P1 to the second position P2 without requiring a large force. In addition, the operator can rotate the operating part 57 located at the first position P1 in the second rotation direction R2 to place it at the third position P3, and release the operating part 57 located at the third position P3 to return the operating part 57 to the first position P1 by the biasing member 55. The dimensions of each member constituting the cutting oxygen valve 50 are set to dimensions that can satisfy these operations.

[0071] Thus, the cutting oxygen valve 50 of the manual gas cutter 1 includes the valve 54 having the valve closing portion 54c capable of closing the flow path through which oxygen flows, and the operation portion 57 connected to the valve 54 and rotatable relative to the valve 54 about the rotation axis O2. The valve 54 moves forward and backward in the vertical direction (advance and retreat direction) B by rotating the operation portion 57 about the rotation axis O2, and can close or open the flow path through which oxygen flows in the main body 10.

[0072] Next, an example of a method of using the manual gas cutter 1 will be described. First, the operator holds the grip 11 with one hand (e.g., the right hand) and operates the preheating oxygen valve 60 and the fuel gas valve 70 with the other hand (e.g., the left hand) to release a mixture of oxygen (preheated oxygen) and fuel gas from the tip 41a of the nozzle 41.

[0073] The operator ignites the mixed gas discharged from the tip 41a of the nozzle 41 with a lighter or the like, and causes a flame P to be discharged from the tip 41a of the nozzle 41. The operator applies the flame P discharged from the nozzle 41 to the part to be cut of the object W to heat the part to be cut of the object W.

[0074] At this time, the operating part 57 of the cutting oxygen valve 50 is located at the first position P1, and the flow path through which the cutting oxygen flows is blocked by the valve 54. Specifically, the valve blocking part 54c blocks the communication hole 51b that connects the first flow path 11a and the cylinder flow path 51a. Therefore, no cutting oxygen is released from the tip 41a of the nozzle 41. In addition, even if the operator does not operate the cutting oxygen valve 50, the operating part 57 is held at the first position P1.

[0075] Next, the worker operates the cutting oxygen valve 50 to open the flow path of the cutting oxygen and release the cutting oxygen from the tip 41a of the nozzle 41. Specifically, the worker holds the trigger 572 of the operating part 57 with the other hand and rotates the operating part 57 from the first position P1 to the second position P2 to move the valve 54 upward B1 and open the communication hole 51b of the cylinder flow path 51a.

[0076] When the communication hole 51b of the cylinder flow path 51a is opened, oxygen (cutting oxygen) flows through the first flow path 11a, the cylinder flow path 51a, and the third flow path 11c in that order, flows into the oxygen release flow path 42 of the nozzle 41, and is released from the tip 41a of the nozzle 41.

[0077] The worker releases cutting oxygen onto a cutting portion of the heated workpiece W to burn the cutting portion, and then cuts the workpiece W by blowing away the burnt cutting portion with the cutting oxygen.

[0078] The operator can instantly open the flow path of the cutting oxygen by rotating the operating part 57 from the first position P1 to the second position P2, and easily cut the workpiece W. After rotating the operating part 57 from the first position P1 to the second position P2, the operating part 57 is held in the second position P2 even if the operator does not operate the cutting oxygen valve 50.

[0079] In the manual gas cutter 1, cutting oxygen can be easily released by rotating the operating part 57 of the cutting oxygen valve 50 from the first position P1 to the second position P2, and therefore, compared to a manual gas cutter equipped with a conventional handle-type cutting oxygen valve, the cutting oxygen airflow is prevented from straying from the cutting portion of the workpiece W, improving workability. By providing the manual gas cutter 1 with the cutting oxygen valve 50, even an operator with little skill can easily perform cutting work such as piercing work.

[0080] In addition, the operating unit 57 located at the second position P2 is held in the second position P2 even if the operator releases it, so there is no need to continue to hold it down with the hand as with a conventional lever-type cutoff oxygen valve. This reduces hand fatigue of the operator and improves workability.

[0081] 3, the trigger 572 of the operating part 57 located at the first position P1 extends upward B1 from the operating part 57. As shown in Fig. 4, the trigger 572 of the operating part 57 located at the second position P2 extends upstream A1 from the operating part 57. Therefore, the operator can easily visually determine whether the operating part 57 is located at the first position P1 or the second position P2, and can easily determine whether the flow path of the cutting oxygen is closed or open.

[0082] When the release of cutting oxygen is to be stopped, the operator grasps the trigger 572 of the operating part 57 located at the second position P2, and rotates the operating part 57 to the first position P1 to close the flow path of the cutting oxygen with the valve 54. When the flow path of the cutting oxygen is closed by the valve 54, the release of the cutting oxygen at the tip 41a of the nozzle 41 is stopped.

[0083] When cutting scrap material or cutting scrap that requires a short cutting time, the worker may frequently open and close the cutting oxygen valve 50. In this case, the worker rotates the operating part 57 located in the first position P1 to the third position P3 to perform a short cutting operation.

[0084] Specifically, the operator presses trigger 572 of operation unit 57 located at first position P1 toward downstream side A2. At this time, the operator may press trigger 572 with the hand that is not holding grip portion 11, or may press trigger 572 with the thumb or the like of the hand that is holding grip portion 11.

[0085] By pressing the trigger 572 toward the downstream side A2, the valve 54 is pulled upward B1, and the communication hole 51b of the cylinder flow passage 51a is opened. When the flow passage for the cutting oxygen is opened, the cutting oxygen flows from the first flow passage 11a into the cylinder flow passage 51a and is discharged from the tip 41a of the nozzle 41, and the operator can perform the cutting work.

[0086] At this time, the operator can release the operating part 57 located in the third position P3 to return the operating part 57 to the first position P1 by the biasing member 55, and close the flow path of the cutting oxygen again by the valve 54. In addition, by pressing the trigger 572 of the operating part 57 returned to the first position P1 toward the downstream side A2 again, the flow path of the cutting oxygen can be opened again, and the cutting operation can be performed.

[0087] In this way, the worker can easily repeatedly open and close the cutting oxygen valve 50 by repeatedly pressing the trigger 572 and releasing the trigger 572. Therefore, even when cutting end material or scrap cutting with a short cutting time, the worker can easily open and close the cutting oxygen valve 50 frequently.

[0088] When returning the operating portion 57 from the third position P3 to the first position P1, the operator may reduce the force pressing the trigger 572 so that the biasing member 55 returns the operating portion 57 to the first position P1 without releasing the trigger 572.

[0089] The manual gas cutter 1 of this embodiment includes a main body 10 in which a flow path (first flow path) 11a through which oxygen flows is formed, and a cutting oxygen valve 50 capable of closing or opening the flow path 11a. The cutting oxygen valve 50 includes a cylinder 51 communicating with the flow path 11a, a valve 54 that is inserted into the cylinder 51 and can move forward and backward and has a valve closing part 54c that can close the flow path 11a, and an operating part that is connected to the valve 54 and can rotate relative to the valve 54 about a rotation axis O2 that extends in a direction different from the forward and backward direction of the valve 54. The valve 54 can move forward and backward in the forward and backward direction by rotating an operating part 57 about the rotation axis O2 as the rotation center, thereby closing or opening the flow path 11a.

[0090] Therefore, compared to a manual gas cutter equipped with a conventional handle (knob) type cutting oxygen valve, the manual gas cutter 1 is less likely to direct the cutting oxygen stream away from the cutting site when releasing cutting oxygen onto the workpiece W. Also, compared to a manual gas cutter equipped with a conventional lever type cutting oxygen valve, the manual gas cutter 1 can reduce hand fatigue when releasing cutting oxygen. As a result, it is possible to provide a manual gas cutter 1 with improved operability.

[0091] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like within the scope of the present invention are also included. In addition, the components shown in the above-mentioned embodiment and the modified examples shown below can be appropriately combined to form a configuration.

[0092] (Variation 1) In the above embodiment, the cutting oxygen valve 50 closes the flow path through which oxygen flows when the trigger 572 of the operation unit 57 is in a state (position) extending upward B1, and opens the flow path through which oxygen flows when the trigger 572 is in a state extending to the upstream side A1, but the aspect of the cutting oxygen valve is not limited to this. The cutting oxygen valve may be configured to open the flow path through which oxygen flows when the trigger of the operation unit is in a state extending upward B1, and to close the flow path through which oxygen flows when the trigger is in a state extending to the upstream side A1.

[0093] In the operating unit 57 of the above embodiment, the distance (first distance) L1 from the rotation axis O2 to the cylinder upper end 52s when the trigger 572 extends upward B1 is smaller than the distance (second distance) L2 from the rotation axis O2 to the cylinder upper end 52s when the trigger 572 extends upstream A1.

[0094] Conversely, the distance from the rotation axis O2 to the upper end of the cylinder when the trigger extends upstream A1 may be smaller than the distance from the rotation axis O2 to the upper end of the cylinder when the trigger extends upward B1.

[0095] In this way, the cutoff oxygen valve can be configured so that when the trigger is extended to the upstream side A1, the oxygen flow path is blocked, and when the trigger is extended to the upward side B1, the oxygen flow path is opened.

[0096] In this case, when cutting scrap material or cutting scrap with a short cutting time, the valve closes the oxygen flow path, and the trigger of the operating part extends to the upstream side A1. In this case, the valve is pulled up to the upper side B1 by pushing the trigger downward B2, and the oxygen flow path is opened. Specifically, by pushing the trigger downward B2, the operating part rotates in the first rotation direction R1 around the end of the upstream side A1 of the second side part as the rotation center, and the valve is pulled up to the upper side B1. As with the cutting oxygen valve 50 of the above embodiment, in which the oxygen flow path can be opened by pushing the trigger 572 to the downstream side A2, the cutting oxygen valve can be easily and frequently opened and closed by repeating the action of pushing the trigger downward B2 and releasing the trigger.

[0097] (Variation 2) In the above embodiment, the operating part 57 of the cutting oxygen valve 50 is rotatable about a rotation axis O2 extending in the width direction C, but the embodiment of the cutting oxygen valve is not limited to this. The operating part of the cutting oxygen valve may be rotatable about a rotation axis extending in the forward and backward direction of the valve.

[0098] For example, the operating unit may be rotatable about an axis O1 that extends in the vertical direction B. In this case, the valve connected to the operating unit via a pivot pin may also be rotatable about the axis O1 together with the operating unit.

[0099] When the operation unit is rotatable about the axis O1, the operator can change the angle of the operation unit relative to the main body to any angle, and can adjust it to an angle that is easy for the operator to operate. The operator adjusts the operation unit to an angle that is easy for the operator to operate by making it rotatable about the axis O1 as the center of rotation, and rotates it about a rotation axis (e.g., rotation axis O2) that extends in a direction different from the axis O1 as the center of rotation to rotate it between a first position and a second position.

[0100] (Variation 3) In the above embodiment, the valve 54 of the cutting oxygen valve 50 is capable of closing the oxygen flow path by the valve closing portion 54c provided at the tip, but the aspect of the cutting oxygen valve is not limited to this.

[0101] The valve of the disconnected oxygen valve may have a valve closing portion at, for example, an intermediate portion in the vertical direction B. For example, with respect to an oxygen flow path extending in the flow direction A, the valve moves in the vertical direction B to block the oxygen flow path. In a valve moving in the vertical direction B, when the flow path and the valve closing portion overlap in a plan view of the flow direction A, the flow path is closed by the valve closing portion, and the flow of oxygen is stopped. Also, when the flow path and the valve closing portion do not overlap in a plan view of the flow direction A, the flow path is opened. In a state where the flow path is opened, for example, an opening provided in the valve may overlap with the flow path in a plan view of the flow direction A. In that case, oxygen flows through the flow path and the opening of the valve. [Explanation of symbols]

[0102] 1 Manual gas cutter 10 Main body 11 Grip 11a First flow path (flow path, flow path through which oxygen flows) 20 Oxygen supply port 30 Fuel gas supply port 40 Torch 41 Crater 50 Disconnected oxygen valve 51 Cylinder section 51a Cylinder passage 51b Communication hole 52 Nut part 52s Cylinder top end 54 Valve 54a Valve core rod 54b Large diameter valve 54c Valve occlusion 55 Pressing member 57 Operation section 571 Operation unit body 571a First Side 571b Second side 572 Trigger 58 Axle Pins 60 Preheating oxygen valve 70 Fuel gas valve P1 first position P2 2nd position P3 third position R1 First rotation direction R2 Second rotation direction O1 axis O2 Rotating Axis L1 First distance (distance) L2 Second distance (distance) L3 Third distance (distance) P flame W Cutting object A Flow direction A1 Upstream A2 downstream side B Vertical direction (forward / backward direction) B1 upper B2 Downward C Width direction

Claims

1. A main body portion having a flow path through which oxygen flows; A cut-off oxygen valve capable of closing or opening the flow path; Equipped with The cutting oxygen valve is A cylinder portion communicating with the flow path; a valve having a valve closing portion that is inserted into the cylinder portion and can advance and retreat and can close the flow path; an operating unit connected to the valve and rotatable relative to the valve about a rotation axis that extends in a direction different from the forward and backward directions of the valve; Equipped with The valve can be moved forward and backward in the forward and backward direction by rotating the operation unit about the rotation axis as a rotation center, to close or open the flow path. Manual gas cutter.

2. the operating portion is rotatable between a first position in which the valve closing portion closes the flow path and a second position in which the valve closing portion opens the flow path; a distance from the rotation shaft to an upper end of the cylinder when the operation unit is located at the first position is smaller than a distance from the rotation shaft to the upper end of the cylinder when the operation unit is located at the second position; 2. The manual gas cutter according to claim 1.

3. The operation unit includes: a first side portion facing the cylinder portion in the advance / retract direction when the operation portion is located at the first position; a second side portion facing the upstream side in the flow direction of the oxygen when the operating portion is located at the first position; having When the operating portion rotates from the first position to the second position, the operating portion rotates from the upstream end of the first side portion while the second side portion is in contact with the upper end of the cylinder portion.

3. The manual gas cutter according to claim 2.

4. The cutting oxygen valve includes a biasing member that biases the valve in the forward and backward directions, the operation unit is rotatable in a second rotation direction opposite to a first rotation direction in which the operation unit rotates from the first position to the second position, When the operating portion located at the first position is rotated in the second rotation direction, the valve closing portion opens the flow path, The operating portion rotated in the second rotation direction is rotated in the first rotation direction by the biasing member.

3. The manual gas cutter according to claim 2.

5. The operation unit includes a trigger protruding in a direction away from the rotation shaft.

2. The manual gas cutter according to claim 1.

6. The operation unit is rotatable about a rotation axis extending in the forward / backward direction.

2. The manual gas cutter according to claim 1.

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