Pressurizing device

Abstract

Provided is a pressurizing device capable of pressurizing an acting body with a substantially constant force by means of a compact structure. The present invention is provided with: a pressure accumulation unit (10); a piston (4) having a small-diameter section (42) inserted into the cylinder section (3) on the pressure accumulation section (10) side and a large-diameter section (41) disposed on the acting body (W) side; and a cylindrical body (5) that extends from the large-diameter section (41) toward the cylinder section (3), and in which a lubricating fluid (F) is held.

Description

Technical Field

[0001] The present invention relates to a pressurizing device for pressurizing an acted object. Background Art

[0002] As a pressurizing device for pressurizing an acted object by utilizing the pressure of a fluid, a cylinder device is sometimes used. A piston moves in a cylinder in response to the pressure of the fluid, thereby pressurizing the acted object.

[0003] For example, the pressurizing device of Patent Document 1 includes a cylinder device, a pump, and an accumulator. When pressurized fluid is supplied from the pump or the accumulator to the cylinder device, the piston moves relatively in the cylinder to pressurize the acted object.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2021-20224 (page 5, Figure 1 ) Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in the pressurizing device of Patent Document 1, in order to pressurize the object with a substantially constant pressurizing force, it is necessary to supply an appropriate fluid to the cylinder at any time using a pump and an accumulator, which causes a problem of increasing the size of the pressurizing device.

[0009] The present invention has been made in view of such a problem, and an object of the present invention is to provide a pressurizing device capable of pressurizing an acted object with a substantially constant force with a compact structure.

[0010] Means for solving problems

[0011] In order to solve the aforementioned problems, the pressurizing device of the present invention comprises: a pressure storage portion; a piston having a small diameter portion inserted into a cylinder portion on the side of the pressure storage portion and a large diameter portion arranged on the side of the acted body; and a cylindrical body extending from the large diameter portion toward the cylinder portion, wherein a lubricating fluid is retained in the cylindrical body.

[0012] Thus, the pressure of the pressure accumulator acting on the small diameter part is dispersed in the large diameter part and transmitted to the acted body, so that the change of the pressure applied to the acted body within the stroke range of the piston can be reduced by a compact structure without using an accumulator or a pump, etc. Moreover, the stroke of the piston can be smoothly performed by using the lubricating fluid retained in the cylindrical body.

[0013] The cylinder portion and the tubular body may be slidable.

[0014] Thus, the movement of the piston is guided by the small diameter portion inside the cylinder and the tubular body outside the cylinder, so that the stroke of the piston is stabilized.

[0015] A breathing hole may be formed on the upper side of the cylindrical body.

[0016] Thus, when the piston moves, the pressure increase and decrease in the cylindrical body can be suppressed by the breathing hole, so that the piston moves smoothly.

[0017] The breathing hole may be provided at a position where the breathing hole is not blocked when the cylindrical body is inserted deepest into the cylinder portion.

[0018] Thus, the piston moves smoothly throughout the entire stroke range of the piston.

[0019] The pressurizing device may include a portion restricting movement of the cylindrical body in the insertion direction.

[0020] Thus, the movement of the cylindrical body in the insertion direction is restricted by the movement restricting portion, thereby reliably preventing the breathing hole from being blocked.

[0021] The lubricating fluid may be maintained so that a liquid surface reaches at least a height position of the small diameter portion when the cylindrical body is inserted deepest into the cylinder portion.

[0022] Thus, the lubricating fluid is supplied to the gap between the cylinder portion and the small diameter portion, so that the piston moves smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a longitudinal sectional view showing the contracted state of the pressurizing device according to the first embodiment of the present invention.

[0024] Figure 2 This is a longitudinal sectional view showing the pressurizing device of Example 1 in an extended state.

[0025] Figure 3 This is a longitudinal sectional view showing a contracted state of a pressurizing device according to a second embodiment of the present invention.

[0026] Figure 4 This is a longitudinal sectional view showing the extended state of the pressurizing device of Example 2. DETAILED DESCRIPTION

[0027] Hereinafter, a mode for implementing the pressurizing device of the present invention will be described based on examples.

[0028] Example 1

[0029] Reference Figure 1 and Figure 2 The pressurizing device of Example 1 is described below. Figure 1The left side of the paper is used as the left side of the pressure device. Figure 1 The right side of the paper is explained as the right side of the pressurizing device.

[0030] like Figure 1 As shown, the pressurizing device 1 uses the pressure of the fluid to pressurize the object W. Assume that the object W of this embodiment is arranged on the right side of the pressurizing device 1 and the position of the pressurized surface W1 is axially Figure 1 The explanation is given by changing in the left and right directions of the paper.

[0031] The pressurizing device 1 mainly includes a housing 2 , a connecting body 3 as a cylinder portion, a piston 4 as a pressure transmitting body, and a cylindrical body 5 as a guide body.

[0032] The housing 2 is cylindrical. The diameter of the right end of the outer peripheral surface of the housing 2 is smaller than the diameter of the left end. That is, a step portion 2a serving as a movement restricting portion is formed annularly on the outer peripheral surface of the housing 2.

[0033] A cover member 6 is connected to the inner peripheral surface of the left end of the housing 2 in a sealed manner by screwing. The cover member 6 has a through hole 6a formed in the center. A bolt 7 is installed in the through hole 6a. In addition, the housing 2 and the cover member 6 may be formed integrally by the same member.

[0034] The connecting body 3 is in the shape of a stepped cylinder having a through hole 3A. The left end of the connecting body 3 is screwed and sealedly connected to the inner circumference of the right end of the housing 2. In addition, in this embodiment, the housing 2 and the connecting body 3 are illustrated as separate bodies, but they can also be formed integrally from the same parts.

[0035] On the outer peripheral surface 3b of the flange extending in the outer diameter direction at the right end of the connecting body 3, annular recesses 3c and 3d recessed in the inner diameter direction are provided axially separately. A sealing ring 8 is fitted in the right annular recess 3c. The left annular recess 3d is shallower than the annular recess 3c and does not fit the sealing ring 8.

[0036] The seal ring 8 is described using an O-ring as an example, but may also be an X-ring, a lip seal, etc. In addition, the annular recess 3d has an oil storage function to enable smooth sliding. In addition, the annular recess 3d may be provided at any position in the axial direction of the outer peripheral surface 3b of the flange as long as it can improve the sliding property.

[0037] The piston 4 has a large diameter portion 41 and a small diameter portion 42. The large diameter portion 41 is in the shape of a disk, and the small diameter portion 42 is in the shape of a column, extending from the center of the large diameter portion 41 toward the left.

[0038] The diameter L1 of the large diameter portion 41 is larger than the diameter L2 of the small diameter portion 42, and in this embodiment is approximately three times the diameter L2. In addition, the diameter L1 of the large diameter portion 41 only needs to be larger than the diameter L2 of the small diameter portion 42, and preferably, the diameter L1 of the large diameter portion 41 is approximately 2 to 5 times the diameter L2 of the small diameter portion 42.

[0039] The large diameter portion 41 has a flat right end face 41a. The end face 41a is configured to be able to directly contact and separate from the acted body W. In detail, the end face 41a can be in surface contact with the pressurized surface W1 of the acted body W. In addition, the end face 41a may be fixed to the pressurized surface W1 of the acted body W and move integrally with the acted body W.

[0040] The small diameter portion 42 is inserted into the through hole 3A of the connecting body 3 so as to be slidable relative to the inner peripheral surface 3a of the connecting body 3. Four annular recessed portions 42a to 42d recessed in the inner diameter direction are provided on the left side of the outer peripheral surface of the small diameter portion 42 and spaced apart in the axial direction.

[0041] The leftmost annular recess 42a and the third annular recess 42c from the left are formed shallower than the second annular recess 42b from the left and the rightmost annular recess 42d. In addition, a seal ring 9 is fitted in the annular recess 42b and the annular recess 42d, respectively. In addition, the seal ring 9 is not fitted in the annular recesses 42a and 42c.

[0042] The seal ring 9 is described using an X-ring as an example, but may also be an O-ring, a lip seal, etc. In addition, a plurality of seal rings 9 are arranged in the axial direction, specifically, two seal rings are arranged, so that oil is hardly leaked to the pressure storage unit 10, and the piston 4 is not easily tilted when the piston 4 moves.

[0043] Furthermore, the annular recessed portions 42a and 42c have a gas storage function and an oil storage function, and can prevent gas leakage and enable smooth sliding.

[0044] The seal ring 9 is slidable in the axial direction relative to the inner peripheral surface 3 a of the connection body 3 , and restricts the movement of the fluid in the axial direction.

[0045] The small diameter portion 42 is inserted into the through hole 3A of the connecting body 3, and a pressure storage portion 10 is formed on the left side of the pressurizing device 1. Specifically, the pressure storage portion 10 is a space surrounded by the housing 2, the connecting body 3, the piston 4, and the cover member 6. The capacity of the pressure storage portion 10 changes by the movement of the piston 4 as described later (see Figure 2 ).

[0046] High-pressure gas G is sealed in the pressure storage unit 10 from the outside through a gas introduction port (not shown) of the plug 7. In other words, the pressure storage unit 10 is a cylinder-shaped gas chamber.

[0047] The diameter D1 of the through hole 3A of the connecting body 3 is smaller than the diameter D2 of the pressure storage part 10, and in the present embodiment is about 1 / 3 times the diameter D2 (D1<D2). In addition, the diameter D1 of the through hole 3A only needs to be smaller than the diameter D2 of the pressure storage part 10, and preferably, the diameter D1 of the through hole 3A is about 1 / 2 to 1 / 5 times the diameter D2 of the pressure storage part 10.

[0048] The right end of the cylindrical body 5 is screwed and sealedly connected to the outer peripheral surface of the large diameter portion 41, and the cylindrical body 5 is integrated with the piston 4. The right end surface of the cylindrical body 5 is arranged to be roughly coplanar with the end surface 41a on the right side of the large diameter portion 41 or arranged at a position closer to the left side than the end surface 41a. Thus, the cylindrical body 5 does not hinder the end surface 41a of the large diameter portion 41 from contacting the surface of the pressurized surface W1 of the body W to be acted on.

[0049] The cylindrical body 5 is externally inserted into the connecting body 3, and the inner peripheral surface 5a of the cylindrical body 5 can slide in the axial direction relative to the outer peripheral surface 3b of the right end of the connecting body 3. Between the inner peripheral surface 5a of the cylindrical body 5 and the outer peripheral surface 3b of the connecting body 3, the sealing ring 8 limits the movement of the fluid in the axial direction.

[0050] On the right side of the pressurizing device 1, the connecting body 3, the large diameter portion 41 of the piston 4, and the cylindrical body 5 constitute a space 11. Oil F as a lubricating fluid is retained in the space 11. The capacity of the space 11 changes as the piston 4 moves as described later (see Figure 2 ).

[0051] A breathing hole 51 is formed in the upper right portion of the cylindrical body 5. That is, the space 11 communicates with the external air space through the breathing hole 51.

[0052] When the piston 4 and the cylindrical body 5 move to the leftmost position, in other words, when the cylindrical body 5 is inserted deepest into the connecting body 3, the end 5b contacts the step 2a of the housing 2.

[0053] Next, use Figure 1 and Figure 2 The contracted state and the extended state of the pressurizing device 1 will be described. The housing 2 is fixed to a fixed body (not shown) and is immobile at least in the axial direction, that is, in the left-right direction.

[0054] like Figure 1 As shown, when the acted body W is arranged at the leftmost position, the piston 4 and the cylindrical body 5 are in the contracted state of the pressurizing device 1, where they have moved to the leftmost position. In the contracted state of the pressurizing device 1, the left end 5b of the cylindrical body 5 abuts against the step 2a of the housing 2, and the movement of the piston 4 and the cylindrical body 5 to the left is restricted.

[0055] In the contracted state of the pressurizing device 1, the capacity of the pressure accumulator 10 becomes minimum within the stroke range of the piston 4, and the gas G is compressed to the maximum. The gas G is restricted from moving to the right space 11 by the seal rings 9, 9. In addition, the annular recesses 42a, 42c function as gas storage portions, and leakage of the gas G can be effectively suppressed.

[0056] The pressure of the gas G in the pressure accumulator 10 acts on the left surface 42e of the small diameter portion 42 (see arrow L10). The pressure of the gas G acting on the left surface 42e of the small diameter portion 42 is transmitted to the acted body W as a stress dispersed in the large diameter portion 41 (see arrow L20).

[0057] Furthermore, in the contracted state of the pressurizing device 1, the breathing hole 51 of the tubular body 5 is arranged on the right side of the connecting body 3. That is, the breathing hole 51 is not closed.

[0058] Furthermore, a water-repellent air-permeable sheet 51 s is provided to block the breathing hole 51 , thereby preventing water from entering the space 11 from the outside and allowing gas to flow.

[0059] The liquid level of the oil F is located near the bottom of the breathing hole 51. Thus, the oil F is supplied to the gap between the outer peripheral surface of the small diameter portion 42 of the piston 4 and the inner peripheral surface 3a of the connecting body 3, and the oil F does not leak from the breathing hole 51 into the air space.

[0060] like Figure 2 As shown, when the position of the pressurized surface W1 of the acted body W is configured at the rightmost position, the piston 4 and the cylindrical body 5 are moved to the rightmost extended state of the pressurizing device 1. In the extended state of the pressurizing device 1, the left end 5b of the cylindrical body 5 abuts against the step 3e of the connecting body 3, and the movement of the piston 4 and the cylindrical body 5 to the right is restricted.

[0061] When the pressurizing device 1 is in the extended state, the capacity of the pressure accumulator 10 is maximized within the stroke range of the piston 4 , and the pressure of the gas G is reduced.

[0062] Furthermore, in the extended state of the pressurizing device 1, the breathing hole 51 moves to the right side away from the connecting body 3 compared to the contracted state of the pressurizing device 1, so the breathing hole 51 is not closed. Furthermore, the liquid level of the oil F is located below the through hole 3A of the connecting body 3.

[0063] From Figure 1 The contracted state of the pressurizing device 1 is toward Figure 2The description will be made when the piston 4 moves to the right while the pressurizing device 1 is in the extended state. Since the diameter D1 of the through hole 3A of the connecting body 3 is smaller than the diameter D2 of the pressure accumulating part 10, the pressure of the gas G is prevented from dropping sharply as the piston 4 moves to the right.

[0064] In other words, in addition to the pressure of the gas G gradually decreasing as the piston 4 moves to the right, the pressure of the gas G is dispersed into small stresses at the large diameter portion 41 and transmitted to the acted body W, so that the change in the pressure applied to the acted body W within the stroke range of the piston 4, that is, the change in the force applied to the acted body W, can be reduced. Therefore, even if the fluid is not supplied from the outside through an accumulator or a pump, etc., the acted body W can be pressurized with a substantially constant force within the stroke range of the piston 4, so that the pressurizing device 1 can be compactly constructed. That is, the piston 4 is a stepped piston 4 in which the diameter L1 is smaller than the diameter L2, and the pressure of the small diameter portion 42 is high pressure and does not change significantly, and the high pressure is maintained. Therefore, compared with the case where the piston is a single piston with the same diameter and the gas G is low pressure (the same pressure as the space portion 11, etc.), the necessary capacity of the pressure storage portion 10 can be reduced.

[0065] Furthermore, the stroke of the piston 4 is smoothed by the oil F supplied to the gap between the outer peripheral surface of the small diameter portion 42 of the piston 4 and the inner peripheral surface 3a of the connecting body 3. In addition, a part of the oil F remaining in the gap between the outer peripheral surface of the small diameter portion 42 and the inner peripheral surface 3a of the connecting body 3 flows into the annular recessed portions 42a, 42c, which contributes to the lubricity of the stroke of the piston 4.

[0066] When the cylindrical body 5 moves to the left as described later, the oil F in the space 11 enters the gap between the outer peripheral surface 3b of the connecting body 3 and the inner peripheral surface 5a of the cylindrical body 5, and the movement of the cylindrical body 5 becomes smooth due to the oil F remaining in the gap.

[0067] Furthermore, the piston 4 is guided in the moving direction by the small diameter portion 42 inside the connecting body 3 and the cylindrical body 5 outside the connecting body 3, so the stroke of the piston 4 is stable. Thus, when the end face 41a of the large diameter portion 41 is in surface contact with the pressurized surface W1 of the acted body W, the acted body W can be pressurized straight to the right by the piston 4, so that the acted body W can be smoothly deformed and even moved.

[0068] And, in Figure 2 The extended state of the pressurizing device 1 is toward Figure 1 When the pressurizing device 1 is in a contracted state and the piston 4 moves to the left, the capacity of the pressure storage part 10 decreases as the piston 4 moves to the left, that is, the pressure of the gas G increases according to the product of the area of ​​the left surface 42e of the small diameter part 42 and the moving distance of the piston 4.

[0069] When Figure 2When the stress of the end surface 41a of the large diameter portion 41 from the acted body W increases, the pressure of the gas G increases as the piston 4 moves to the left, thereby balancing the force pressing the piston 4 to the right and the force pressing to the left. That is, the stroke of the piston 4 can be ensured even if the gas G is not discharged to the outside.

[0070] Furthermore, the stroke of the piston 4 can be smoothly performed by utilizing the oil F remaining in the gap between the outer peripheral surface of the small diameter portion 42 and the inner peripheral surface 3 a of the connecting body 3 .

[0071] When the capacity of the space 11 gradually decreases and the liquid level of the oil F reaches the through hole 3A of the connecting body 3 , the oil F is supplied to the gap between the outer peripheral surface of the small diameter portion 42 of the piston 4 and the inner peripheral surface 3 a of the connecting body 3 .

[0072] Furthermore, the oil F in the space 11 enters the gap between the outer peripheral surface 3b of the connecting body 3 and the inner peripheral surface 5a of the cylindrical body 5, and the movement of the cylindrical body 5 also becomes smooth. A part of the oil F remaining in the gap between the outer peripheral surface 3b of the connecting body 3 and the inner peripheral surface 5a of the cylindrical body 5 flows into the annular recess 3d, which contributes to the lubricity of the stroke of the cylindrical body 5.

[0073] Furthermore, since the breathing hole 51 is not closed throughout the entire stroke range of the piston 4 , it is possible to prevent the pressure in the space 11 from rising, and the piston 4 can be caused to perform a stable stroke.

[0074] As described above, the pressure of the pressure accumulator 10 acting on the small diameter portion 42 is dispersed in the large diameter portion 41 and transmitted to the acted body W, so that the change of the pressure applied to the acted body W within the stroke range of the piston 4 can be reduced by a compact structure that does not use an accumulator or a pump. In addition, the oil F is retained in the space portion 11 located in the cylindrical body 5, and the stroke of the piston 4 can be smoothly performed by using the oil F.

[0075] The cylindrical body 5 is slidable relative to the outer peripheral surface 3b of the connecting body 3. Thus, the piston 4 is guided in the moving direction by the small diameter portion 42 inside the connecting body 3 and the cylindrical body 5 outside the connecting body 3, so that the stroke of the piston 4 is stabilized.

[0076] Furthermore, a breathing hole 51 is formed above the cylindrical body 5. Thus, when the piston 4 moves, the pressure increase and decrease in the space portion 11 can be suppressed by the breathing hole 51, so that the piston 4 moves smoothly.

[0077] Furthermore, the breathing hole 51 is provided at a position where it is not blocked when the cylindrical body 5 is inserted deepest into the connecting body 3. Thus, the breathing hole 51 is not blocked during the entire stroke of the piston 4, thereby preventing the pressure in the space 11 from rising due to the stroke of the piston 4.

[0078] Furthermore, when the cylindrical body 5 is inserted deepest into the connecting body 3 , it abuts against the step portion 2 a of the housing 2 , and movement of the cylindrical body 5 in the insertion direction is restricted, thereby reliably preventing the breathing hole 51 from being blocked.

[0079] The oil F is maintained so that the liquid level of the oil F reaches at least the height of the small diameter portion 42 when the cylindrical body 5 is inserted deepest into the connecting body 3. Thus, the oil F is supplied to the gap between the connecting body 3 and the small diameter portion 42, so that the piston 4 moves smoothly.

[0080] Furthermore, since the cylindrical body 5 is attached to the large diameter portion 41 and extends to the left in parallel along the small diameter portion 42 , the entire length of the pressurizing device 1 is short and compact.

[0081] Example 2

[0082] Next, refer to Figure 3 and Figure 4 The pressurizing device of Example 2 will be described. In addition, description of the same structure as that of the above-mentioned Example 1 will be omitted.

[0083] like Figure 3 As shown, in the pressurizing device 100 of the second embodiment, the left end of the cylindrical body 50 is connected to the right end of the connecting body 30 in a sealed manner by screwing. Alternatively, the connecting body 30 and the cylindrical body 50 may be integrally formed of the same member.

[0084] The breathing hole 510 of the cylindrical body 50 is provided at the upper left side of the cylindrical body 50 and is closed by a water-repellent air-permeable sheet 510s. In addition, a ring-shaped cover 520 is attached to the right end of the cylindrical body 50.

[0085] The piston 40 has a large diameter portion 410, a small diameter portion 420, and a middle diameter portion 430. The middle diameter portion 430 is cylindrical and extends from the center of the large diameter portion 410 toward the right. The diameter of the middle diameter portion 430 is smaller than that of the large diameter portion 410 and larger than that of the small diameter portion 420.

[0086] The middle diameter portion 430 is inserted into the through hole 520A of the cover body 520. At the right end of the middle diameter portion 430, a locking member 12 as a movement restricting portion having a U-shape in cross-sectional view is arranged on the right side of the cover body 520.

[0087] The flat right surface 12 a of the locking member 12 is in contact with the pressurized surface W1 of the object W being acted upon.

[0088] exist Figure 3 In the contracted state of the pressurizing device 100 shown, the locking member 12 is in contact with the cover body 520, and the movement of the piston 40 to the left is restricted.

[0089] Furthermore, the breathing hole 510 of the cylindrical body 50 is arranged on the left side of the large diameter portion 410 of the piston 40 .

[0090] Furthermore, since the liquid level of the oil F is located above the through hole 30A of the connection body 30 , the oil F can be supplied to the gap between the small diameter portion 420 and the connection body 30 .

[0091] exist Figure 4 In the extended state of the pressurizing device 100 shown, the piston 40 moves to the right compared to the contracted state of the pressurizing device 100 , so the breathing hole 510 is not closed by the large diameter portion 410 of the piston 40 .

[0092] That is, the breathing hole 510 is not closed within the entire stroke range of the piston 40 , and thus it is possible to prevent the pressure in the space portion 110 from increasing due to the stroke of the piston 40 .

[0093] Furthermore, when the piston 40 moves left and right, the oil F enters the gap between the inner peripheral surface of the cylindrical body 50 and the outer peripheral surface of the large diameter portion 410 , thereby enabling the stroke of the piston 40 to proceed smoothly.

[0094] As mentioned above, although the embodiment of the present invention is described with reference to the drawings, the specific structure is not limited to these embodiments, and the change and addition within the range which does not deviate from the summary of the present invention are also included in the present invention.

[0095] Furthermore, in the above-mentioned first and second embodiments, the mode in which the gas is pressurized in the pressure accumulation section is exemplified, but a liquid such as oil or a mixture of liquid and gas may be sealed in the pressure accumulation section.

[0096] Furthermore, in the above-mentioned embodiments 1 and 2, the method of guiding the stroke of the piston by the cylindrical body and the small-diameter portion is illustrated, but it is not limited to this, and other guide bodies other than the cylindrical body and the small-diameter portion may be provided. For example, it is also possible that a guide hole is provided in the cylinder portion, and a guide pin is provided in the piston, and the stroke of the piston is guided by the guide hole and the guide pin sliding in the stroke direction. Furthermore, although an example in which the cylindrical body is guided by the outer periphery of the housing of the pressure storage portion is described, the cylindrical body may also be guided by the outer periphery of the connecting body.

[0097] Furthermore, in the above-mentioned first and second embodiments, the large diameter portion of the piston is in direct contact with the acted body, but other components may be interposed between the large diameter portion of the piston and the acted body.

[0098] Furthermore, in the above-mentioned embodiments 1 and 2, the breathing holes 51 and 510 are provided in the cylindrical bodies 5 and 50, but it is also possible that the breathing holes 51 and 510 are not provided and the pressure change of the space portion 11 is also utilized in addition to the pressure change of the pressure storage portion 10.

[0099] Furthermore, in the aforementioned embodiments 1 and 2, the annular recesses 3d and 42a and 42c are illustrated as spaces for storing fluid, but a component having a bearing function, a component for improving lubricity, or a component for suppressing eccentricity may be inserted into the space.

[0100] Description of symbols

[0101] 1: pressurizing device; 2a: step portion (movement limiting portion); 3: connecting body (cylinder portion); 4: piston (pressure transmitting body); 5: cylindrical body; 10: pressure storage portion; 11: space portion; 12: locking component (movement limiting portion); 30: connecting body (cylinder portion); 40: piston (pressure transmitting body); 41: large diameter portion; 42: small diameter portion; 50: cylindrical body; 51: breathing hole; 100: pressurizing device; 110: space portion; 410: large diameter portion; 420: small diameter portion; 430: middle diameter portion; 510: breathing hole; F: oil; G: gas; W: acted body.

Claims

1. A pressurizing device, comprising: Pressure accumulator; a piston having a small diameter portion inserted into the cylinder portion on the pressure storage portion side and a large diameter portion disposed on the side of the acted body; and a cylindrical body extending from the large diameter portion toward the cylinder portion, A lubricating fluid is retained in the cylindrical body.

2. The pressurizing device according to claim 1, wherein: The cylinder portion and the cylindrical body are slidable.

3. The pressurizing device according to claim 1, wherein: A breathing hole is formed on the upper side of the cylindrical body.

4. The pressurizing device according to claim 3, wherein: The breathing hole is provided at a position where it will not be blocked when the cylindrical body is inserted deepest into the cylinder.

5. The pressurizing device according to claim 4, wherein: The pressurizing device includes a movement restricting portion of the cylindrical body in the insertion direction.

6. The pressurizing device according to claim 1, wherein: The lubricating fluid is maintained so that the liquid surface reaches at least the height position of the small diameter portion when the cylindrical body is inserted deepest into the cylinder portion.

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