TWI836723B - Double-acting cylinder with retraction cushion function - Google Patents

Abstract

Disclosed is a double-acting cylinder with a retraction cushion function, comprising a cylinder body and a shaft slidably disposed in the cylinder body, wherein the shaft has a cushion portion which is provided to close, when the shaft retracts backward, a longitudinal connecting hole between a rear chamber space and a rear fluid connecting hole of the cylinder body to leave only a gap flow channel so as to slow down the retraction speed of the shaft by reducing the outflow of a driving fluid in the rear chamber space.

Description

Double-acting cylinder with retraction cushion

The present invention relates to a double-acting cylinder, and in particular to a double-acting cylinder with retraction cushioning.

A double-acting cylinder is a cylinder in which the driving fluid acts on both sides of the piston alternately. By causing the driving fluid to act on one side of the piston, the piston can be extended and actuated. By causing the driving fluid to act on the piston On the other side, the piston can be retracted. Double-acting cylinders are mainly used in situations where external force cannot be used to retract the piston, and can also be used in situations where higher force is required in both extending and retracting directions.

Due to the large force of the driving fluid, the piston is prone to violently hit the rear end of the cylinder due to inertia when it retracts to the end. In serious cases, it may even be damaged, so there is a need for improvement.

Therefore, the purpose of the present invention is to provide a double-acting cylinder with retraction buffer to solve the problems of the prior art.

The present invention solves the problems of the prior art by providing a double-acting cylinder with a retraction buffer, comprising: a cylinder body having a cylinder chamber, a front fluid inlet and outlet, and a rear fluid inlet and outlet, the front fluid inlet and outlet being connected to the front side of the cylinder chamber, the rear end of the cylinder chamber having a longitudinal connecting hole, the rear fluid inlet and outlet being connected to the cylinder chamber through the longitudinal connecting hole; and an axis having a piston part and a buffer part, the piston part being located at one end of the axis, the axis being arranged in such a way that the outer diameter surface of the piston part corresponds to the inner diameter surface of the cylinder body. The piston is longitudinally slidably sleeved in the cylinder chamber of the cylinder body, and the cylinder chamber is divided into a front cylinder chamber space and a rear cylinder chamber space by the piston portion. The front cylinder chamber space is connected to the front fluid inlet and outlet, and the rear cylinder chamber space is connected to the rear fluid inlet and outlet via the longitudinal connecting hole, so that a driving fluid is input from the rear fluid inlet and outlet to the rear cylinder chamber space of the cylinder chamber, so that the piston portion is pushed to drive the axis to extend longitudinally forward, and at the same time, the driving fluid in the front cylinder chamber space of the cylinder chamber flows out to the front fluid inlet and outlet, and the driving fluid is input from the front fluid inlet and outlet to the rear cylinder chamber space of the cylinder chamber. The fluid inlet and outlet input the driving fluid into the front cylinder chamber space of the cylinder chamber, so that the piston part is pushed to drive the axis to retract longitudinally backward, and at the same time, the driving fluid in the rear cylinder chamber space of the cylinder chamber flows out to the rear fluid inlet and outlet, the buffer part elastically protrudes longitudinally backward from the piston part and longitudinally corresponds to the longitudinal through hole of the cylinder chamber, and the rear side surface of the buffer part is provided with a gap groove, wherein the buffer part is arranged: when the axis retracts longitudinally backward, the buffer part elastically abuts against the longitudinal through hole correspondingly with the backward displacement of the piston part The rear side of the buffer portion is pressed against the front side of the longitudinal connecting hole by the elastic force caused by the elastic abutment, and the longitudinal connecting hole is closed by leaving only a gap flow channel sandwiched between the gap groove of the buffer portion and the front side of the longitudinal connecting hole. The flow channel cross-sectional area of the gap flow channel is smaller than the flow channel cross-sectional area of the longitudinal connecting hole, so that the outflow of the driving fluid from the rear cylinder chamber space through the longitudinal connecting hole to the rear fluid inlet and outlet is limited by the gap flow channel and reduced, thereby slowing down the retraction speed of the axis.

In one embodiment of the present invention, a double-acting cylinder with a retraction buffer is provided, wherein the buffer portion includes a support block and an elastic member, the support block longitudinally corresponds to the longitudinal through hole, the gap groove is formed on the rear side of the support block, and the elastic member is elastically connected between the support block and the piston portion, so that when the piston portion moves backward, the support block elastically abuts against the longitudinal through hole in a corresponding manner.

In one embodiment of the present invention, a double-acting cylinder with retraction buffer is provided, wherein the gap groove extends transversely inward from a peripheral position of the rear side surface of the abutment block to an inner position of the rear side surface of the abutment block, the radius of the peripheral position is greater than the radius of the longitudinal connecting hole, and the radius of the inner position is less than the radius of the longitudinal connecting hole, so that when the abutment block elastically abuts against the longitudinal connecting hole, the gap flow channel is transversely connected to the rear cylinder chamber space at the peripheral position and connected to the longitudinal connecting hole at the inner position.

In one embodiment of the present invention, a double-acting cylinder with retraction buffer is provided, wherein a retraction groove is formed on the rear side of the piston portion for correspondingly accommodating the abutment block to allow the piston portion to move backward to a position where the rear side of the piston portion abuts against the front side of the longitudinal through hole.

In one embodiment of the present invention, a double-acting cylinder with a retraction buffer is provided, wherein the buffer portion further includes a guide rod, which longitudinally corresponds to the longitudinal connecting hole and extends longitudinally backward from the piston portion, and the abutment block is slidably arranged on the guide rod to ensure the longitudinal sliding of the abutment block by the guide rod, wherein when the axis retracts longitudinally backward, the guide rod is displaced into the longitudinal connecting hole in a corresponding manner with the backward displacement of the piston portion in a manner that the guide rod and the cylinder chamber do not abut against each other.

In one embodiment of the present invention, a double-acting cylinder with retraction buffer is provided, wherein the elastic member is a compression spring, which is sleeved on the guide rod and elastically connected between the abutment block and the piston portion.

In one embodiment of the present invention, a double-acting cylinder with retraction buffering is provided, wherein the buffering part further includes a guide member, longitudinally corresponding to the longitudinal communication hole and further from the rear side of the buffering part. Projecting backward, the guide member has a tapered shape with a radius tapering from front to back, wherein when the axis is retracted longitudinally backward, the guide member is displaced rearwardly into the longitudinal communication along with the buffer portion. hole, and the tapered shape guides the buffer portion to correspondingly elastically abut against the longitudinal communication hole.

In one embodiment of the present invention, a double-acting cylinder with retraction buffer is provided, wherein the abutment block is a buffer pad body.

In one embodiment of the present invention, a double-acting cylinder with retraction buffer is provided, wherein the front fluid inlet and outlet passes through the outer peripheral wall of the cylinder and is laterally connected to the front cylinder chamber space.

Through the technical means adopted by the present invention, the double-acting cylinder with retraction buffer of the present invention can, when the axis retracts longitudinally backward, use the buffer part to seal the longitudinal connecting hole at the rear end of the cylinder body until only the gap flow channel is left, so that the outflow of the driving fluid through the longitudinal connecting hole is restricted and reduced, thereby reducing the retraction speed of the buffer axis to solve the problem of the prior art. In addition, the double-acting cylinder with retraction buffer of the present invention can effectively provide the retraction buffer function without the need for precise external flow control of the driving fluid, so that it is more convenient to be applied in various mechanisms.

100:Double-acting cylinder with retraction buffer

1: Cylinder body

10:Cylinder room

101: Front cylinder room space

102: Rear cylinder room space

11: Front fluid inlet and outlet

12:Rear fluid inlet and outlet

121: Longitudinal communicating hole

2: Axis

3: Piston part

31: Retraction groove

4: Buffer section

41: against block

411: Gap groove

42: Elastic parts

43:Guide rod

44: Guide parts

C: Gap channel

Rh: Radius size

Ri: Radius distance

Ro: Radius distance

[Figure 1] is a three-dimensional schematic diagram showing a double-acting cylinder with retraction cushioning according to an embodiment of the present invention; [Figure 2] is a cross-sectional schematic diagram showing the double-acting cylinder with retraction cushioning according to an embodiment of the present invention when extended; [Figure 3] is a cross-sectional schematic diagram showing the double-acting cylinder with retraction cushioning according to an embodiment of the present invention when retracted; [Figure 4] is a cross-sectional schematic diagram showing the double-acting cylinder with retraction cushioning according to an embodiment of the present invention when retracted; [Figure 5] is a cross-sectional schematic diagram showing the double-acting cylinder with retraction cushioning according to an embodiment of the present invention when retracted.

The following describes the implementation of the present invention based on Figures 1 to 5. The description is not intended to limit the implementation of the present invention, but is an example of the implementation of the present invention.

As shown in Figures 1 to 5, a double-acting cylinder 100 with retraction buffering according to an embodiment of the present invention includes: a cylinder 1 and an axis 2.

As shown in Figures 1 to 5, the cylinder 1 has a cylinder chamber 10, a front fluid inlet and outlet 11, and a rear fluid inlet and outlet 12. The front fluid inlet and outlet 11 is connected to the front side of the cylinder chamber 10. , the rear end of the cylinder chamber 10 has a longitudinal communication hole 121 , and the rear fluid inlet and outlet 12 is connected to the cylinder chamber 10 through the longitudinal communication hole 121 .

As shown in Figures 1 to 5, the axis 2 has a piston part 3 and a buffer part 4. The piston part 3 is located at one end of the axis 2. The axis 2 is outside the piston part 3. The radial surface corresponds to the inner diameter surface of the cylinder 1 and is slidably sleeved longitudinally in the cylinder chamber 10 of the cylinder 1 , and the cylinder chamber 10 is divided into a front cylinder chamber space by the piston part 3 101 and a rear cylinder chamber space 102, the front cylinder chamber space 101 is connected to the front fluid inlet and outlet 11, the rear cylinder chamber space 102 is connected to the rear fluid inlet and outlet 12 through the longitudinal communication hole 121, so as to pass through the The rear fluid inlet and outlet 12 inputs a driving fluid into the rear cylinder space 102 of the cylinder chamber 10, so that the piston part 3 is pushed to drive the axis 2 to extend longitudinally forward, and at the same time, the cylinder chamber 10 The driving fluid in the front cylinder chamber space 101 flows out to the front fluid inlet and outlet 11, and by entering from the front fluid The outlet 11 inputs the driving fluid into the front cylinder chamber space 101 of the cylinder chamber 10, so that the piston part 3 is pushed to drive the axis 2 to retract longitudinally backward, and at the same time, the rear cylinder chamber space 102 of the cylinder chamber 10 The driving fluid inside flows out to the rear fluid inlet 12 .

As shown in FIGS. 2 to 5, the buffer portion 4 elastically protrudes longitudinally backward from the piston portion 3 and longitudinally corresponds to the longitudinal connecting hole 121 of the cylinder chamber 10, and a gap groove 411 is provided on the rear side of the buffer portion 4, wherein the buffer portion 4 is arranged so that: when the axis 2 retracts longitudinally backward, the buffer portion 4 elastically abuts against the longitudinal connecting hole 121 (as shown in FIG. 3) correspondingly as the piston portion 3 moves backward, and the elastic force caused by the elastic abutment causes the rear side of the buffer portion 4 to be pressed against the longitudinal connecting hole 1 21 front side (as shown in FIG. 4), and the longitudinal connecting hole 121 is closed by leaving only a gap flow channel C sandwiched between the gap groove 411 of the buffer portion 4 and the front side of the longitudinal connecting hole 121. The flow channel cross-sectional area of the gap flow channel C is smaller than the flow channel cross-sectional area of the longitudinal connecting hole 121, so that the outflow of the driving fluid from the rear cylinder chamber space 102 through the longitudinal connecting hole 121 to the rear fluid inlet and outlet 12 is limited by the gap flow channel C and reduced, thereby slowing down the retraction speed of the shaft 2.

As shown in Figures 2 to 5, a double-acting cylinder 100 with retraction buffer according to an embodiment of the present invention, wherein the buffer portion 4 includes a support block 41 and an elastic member 42, the support block 41 longitudinally corresponds to the longitudinal connecting hole 121, the gap groove 411 is formed on the rear side of the support block 41, and the elastic member 42 is elastically connected between the support block 41 and the piston portion 3, so that when the piston portion 3 moves backward, the support block 41 elastically abuts against the longitudinal connecting hole 121 accordingly.

As shown in FIGS. 2 to 5, in a double-acting cylinder 100 with retraction buffer according to an embodiment of the present invention, the gap groove 411 extends transversely inward from a peripheral position of the rear side of the abutment block 41 to an inner position of the rear side of the abutment block 41, and the radius Ro of the peripheral position is greater than half of the longitudinal through hole 121. The radius Rh of the inner position is smaller than the radius Rh of the longitudinal connecting hole 121, so that when the abutment block 41 elastically abuts against the longitudinal connecting hole 121, the gap flow channel C is horizontally connected to the rear cylinder chamber space 102 at the peripheral position and is connected to the longitudinal connecting hole 121 at the inner position.

As shown in Figures 2 to 5, according to an embodiment of the double-acting cylinder 100 with retraction buffering of the present invention, an indented groove 31 is formed on the rear side of the piston part 3 for correspondingly accommodating the piston part 3. The abutting block 41 allows the piston part 3 to move backward to a position where the rear side of the piston part 3 abuts the front side of the longitudinal communication hole 121 (as shown in Figure 5).

As shown in FIGS. 2 to 5, according to an embodiment of the present invention, a double-acting cylinder 100 with retraction buffer, the buffer portion 4 further includes a guide rod 43, which longitudinally corresponds to the longitudinal connecting hole 121 and extends longitudinally backward from the piston portion 3, and the abutment block 41 is slidably disposed on the guide rod 43, so that the longitudinal sliding of the abutment block 41 is ensured by the guide rod 43, wherein when the axis 2 retracts longitudinally backward, the guide rod 43 is displaced into the longitudinal connecting hole 121 in a manner that the guide rod 43 and the cylinder chamber 10 do not abut against each other as the piston portion 3 moves backward (as shown in FIGS. 3, 4, and 5).

As shown in Figures 2 to 5, according to an embodiment of the double-acting cylinder 100 with retraction buffering of the present invention, the elastic member 42 is a compression spring, which is sleeved on the guide rod 43 and elastically It is connected between the resisting block 41 and the piston part 3 .

As shown in FIGS. 2 to 5 , according to an embodiment of the double-acting cylinder 100 with retraction buffering of the present invention, the buffering part 4 further includes a guide 44 longitudinally corresponding to the longitudinal communication hole 121 The side surface further protrudes rearward from the buffer portion 4, and the guide member 44 has a tapered shape with a radius tapering from front to back. When the axis 2 retracts longitudinally backward, the guide member 44 is As the buffer portion 4 moves backward into the longitudinal communication hole 121 , the buffer portion 4 is guided to correspondingly elastically abut against the longitudinal communication hole 121 through the tapered surface shape.

As shown in Figures 2 to 5, in a double-acting cylinder 100 with retraction buffer according to an embodiment of the present invention, the abutment block 41 is a buffer pad. Specifically, the buffer pad refers to a pad made of a buffer material, which absorbs and reduces the impact force when the abutment block 41 abuts against the longitudinal through hole 121, and can help the rear side of the abutment block 41 and the front side of the longitudinal through hole 121 to fit more closely to reduce the generation of gaps.

As shown in Figures 2 to 5, according to an embodiment of the present invention, the double-acting cylinder 100 with retraction buffer, the front fluid inlet and outlet 11 passes through the outer peripheral wall of the cylinder body 1 and is horizontally connected to the front cylinder chamber space 101. Of course, the present invention is not limited to this. In other embodiments, the front fluid inlet and outlet 11 can also be connected to the front cylinder chamber space 101 in other ways. For example, the front fluid inlet and outlet 11 can pass through the end wall of the cylinder body 1 and be vertically connected to the front cylinder chamber space 101.

Next, referring to Figures 2 to 5, the actuation of the double-acting cylinder 100 with retraction buffer of an embodiment of the present invention will be described as follows.

As shown in Figure 2 and shown in Figures 3 to 5, when the driving fluid is input from the rear fluid inlet and outlet 12, the driving fluid flows into the rear of the cylinder chamber 10 through the longitudinal communication hole 121. The cylinder chamber space 102 causes the piston part 3 to be pushed forward by the driving fluid from the rear cylinder chamber space 102 to displace forward. At the same time, the driving fluid in the front cylinder chamber space 101 is pushed by the piston part 3 and flows out to the front fluid inlet and outlet 11 . Thereby, the piston part 3 drives the axis 2 to extend forward longitudinally.

As shown in Figure 3, when the driving fluid is input from the front fluid inlet and outlet 11, the driving fluid flows into the front cylinder chamber space 101 of the cylinder chamber 10, causing the piston part 3 to receive pressure from the front cylinder chamber space 101. The driving fluid within the body pushes it toward the rearward displacement. At the same time, the driving fluid in the rear cylinder chamber space 102 is pushed by the piston part 3 and flows out to the rear fluid inlet and outlet 12 through the longitudinal communication hole 121 . Therefore, the piston part 3 drives the axis 2 to retract longitudinally together.

As shown in Figure 3 and combined with Figures 2, 4 and 5, when the axis 2 is longitudinally retracted backward and displaced to a position in contact with the longitudinal communication hole 121, the buffer portion 4 It will correspondingly abut against the longitudinal communication hole 121 , thereby sealing the front side of the longitudinal communication hole 121 . Moreover, because the gap groove 411 is provided on the rear side of the buffer portion 4, the longitudinal communication hole 121 will not be completely closed, but the gap groove 411 and the longitudinal communication hole will be left in the buffer portion 4. The gap flow channel C sandwiched between the front sides of 121 allows the rear cylinder chamber space 102 to communicate with the rear fluid inlet and outlet 12 only through the gap flow channel C.

As shown in Figures 4 and 5 and in conjunction with Figures 2 and 3, the communication between the rear fluid inlet and outlet 12 and the rear cylinder chamber space 102 changes from the original large diameter of the longitudinal communication hole 121. After the flow channel cross-sectional area is reduced to the small flow channel cross-sectional area of the gap flow channel C, the outflow of the driving fluid in the rear cylinder chamber space 102 to the rear fluid inlet and outlet 12 will be reduced due to the reduction in the flow channel cross-sectional area. decrease. In this case, the rearward displacement speed of the piston part 3 will also slow down as the outflow of the driving fluid in the rear cylinder chamber space 102 decreases, thereby slowing down the retraction speed of the axis 2 to reach Retract the role of buffering.

With the above structure, the double-acting cylinder 100 with retraction buffering of the present invention can seal the longitudinal communication hole 121 at the rear end of the cylinder 1 with the buffering portion 4 when the axis 2 is longitudinally retracted rearward. Leaving only the gap flow channel C limits and reduces the outflow of the driving fluid through the longitudinal communication hole 121 , thereby slowing down the retraction speed of the shaft 2 to solve the problems of the conventional technology. Moreover, the double-acting cylinder 100 with retraction buffering of the present invention can effectively provide a retraction buffering function without requiring precise external flow control of the driving fluid, thereby making it more convenient to apply to various mechanisms. middle.

The above descriptions and explanations are only descriptions of the preferred embodiments of the present invention. Those with ordinary knowledge of this technology may make other modifications based on the patent scope defined below and the above explanations, but these modifications should still be made. It is for the spirit of the present invention and within the scope of rights of the present invention.

100: Double-acting cylinder with retraction buffer

1: Cylinder body

10: Tank room

101: Front cylinder room space

102: Rear cylinder room space

11: Front fluid inlet and outlet

12: Rear fluid inlet and outlet

121: Longitudinal connecting hole

2: Axis

3: Piston part

31:Inner shrink groove

4: Buffer part

41: against block

42: Elastic parts

43:Guide rod

44: Guide parts

C: Gap flow channel

Claims (9)

A double-acting cylinder with retraction buffer, including: A cylinder body has a cylinder chamber, a front fluid inlet and outlet, and a rear fluid inlet and outlet. The front fluid inlet and outlet is connected to the front side of the cylinder chamber. The rear end of the cylinder chamber has a longitudinal communication hole. The rear fluid inlet and outlet The outlet is connected to the cylinder chamber through the longitudinal communication hole; and An axis has a piston part and a buffer part. The piston part is located at one end of the axis. The axis slides longitudinally in such a way that the outer diameter surface of the piston part corresponds to the inner diameter surface of the cylinder. It is sleeved in the cylinder chamber of the cylinder body, and the piston part divides the cylinder chamber into a front cylinder chamber space and a rear cylinder chamber space. The front cylinder chamber space is connected to the front fluid inlet and outlet, and the rear cylinder chamber space is connected to the front fluid inlet and outlet. The cylinder chamber space is connected to the rear fluid inlet and outlet through the longitudinal communication hole, so that a driving fluid is input from the rear fluid inlet and outlet to the rear cylinder chamber space of the cylinder chamber, so that the piston portion is pushed to drive the The axis extends forward longitudinally, and at the same time, the driving fluid in the front cylinder chamber space of the cylinder chamber flows out to the front fluid inlet and outlet, and the driving fluid is input from the front fluid inlet and outlet to the cylinder chamber. The front cylinder chamber space causes the piston portion to be pushed to drive the axis to retract longitudinally backward, and at the same time, the driving fluid in the rear cylinder chamber space of the cylinder chamber flows out to the rear fluid inlet and outlet. The buffer portion is The longitudinal communication hole protrudes longitudinally and rearward from the piston portion and corresponds longitudinally to the longitudinal communication hole of the cylinder chamber. A clearance groove is provided on the rear side of the buffer portion, wherein the buffer portion is configured to: When the axis retracts longitudinally backward, the buffer portion elastically abuts the longitudinal communication hole as the piston moves rearward, and the rear side surface of the buffer portion is pressed by the elastic force caused by the elastic abutment. Close to the front side of the longitudinal communication hole, the longitudinal communication hole is closed in a manner that only leaves a gap flow channel sandwiched between the gap groove of the buffer portion and the front side of the longitudinal communication hole, the The flow channel cross-sectional area of the gap flow channel is smaller than the flow channel cross-sectional area of the longitudinal communication hole, so that the outflow of the driving fluid from the rear cylinder chamber space to the rear fluid inlet through the longitudinal communication hole is limited by the gap flow and decreases, thereby slowing down the retraction speed of the axis. The double-acting cylinder with retraction buffering as claimed in claim 1, wherein the buffering part includes a resisting block and an elastic member, the resisting block longitudinally corresponds to the longitudinal communication hole, and the gap groove is formed in the On the rear side of the abutment block, the elastic member is elastically connected between the abutment block and the piston part, so that when the piston part is displaced backward, the abutment block correspondingly elastically abuts the longitudinal communication hole. The double-acting cylinder with retraction buffer as described in claim 2, wherein the clearance groove extends laterally inward from a circumferential position of the rear side of the abutment block to an inner position of the rear side of the abutment block, The radius distance where the peripheral edge is located is greater than the radius size of the longitudinal communication hole, and the radius distance where the inner position is located is smaller than the radius size of the longitudinal communication hole, so that the abutment block can correspondingly elastically abut against the longitudinal communication hole. At this time, the gap flow channel is laterally connected to the rear cylinder chamber space at the peripheral position and connected to the longitudinal communication hole at the inner position. As described in claim 2, a double-acting cylinder with retraction buffer is formed with a retraction groove on the rear side of the piston portion for correspondingly accommodating the abutment block to allow the piston portion to move backward to a position where the rear side of the piston portion abuts against the front side of the longitudinal connecting hole. A double-acting cylinder with a retraction buffer as described in any one of claims 2 to 4, wherein the buffer portion further includes a guide rod, which longitudinally corresponds to the longitudinal connecting hole and extends longitudinally backward from the piston portion, and the abutment block is slidably arranged on the guide rod to ensure the longitudinal sliding of the abutment block by the guide rod, wherein when the axis retracts longitudinally backward, the guide rod is displaced into the longitudinal connecting hole in a corresponding manner with the backward displacement of the piston portion in a manner that the guide rod and the cylinder chamber do not abut against each other. A double-acting cylinder with retraction buffer as described in claim 5, wherein the elastic member is a compression spring, which is sleeved on the guide rod and elastically connected between the abutment block and the piston part. The double-acting cylinder with retraction buffering according to any one of claims 1 to 3, wherein the buffering part further includes a guide member, the longitudinal direction corresponding to the longitudinal communication hole and the side surface further protruding backward from the rear side of the buffering part. Extending, the guide member has a tapered shape with a radius tapering from front to back, wherein when the axis is retracted longitudinally backward, the guide member is displaced backward along with the buffer portion and enters the longitudinal communication hole, And the tapered surface shape guides the buffer portion to correspondingly elastically abut the longitudinal communication hole. A double-acting cylinder with retraction buffer as described in claim 2, wherein the abutment block is a buffer pad. A double-acting cylinder with retraction buffer as described in claim 1, wherein the front fluid inlet and outlet passes through the outer peripheral wall of the cylinder body and is laterally connected to the front cylinder chamber space.

Images