Hydraulic piston design

Abstract

A system for engaging clutch plate packs using hydraulic pistons has been developed. The system may be used with an automatic transmission or other parts of a powertrain of a vehicle. The system includes a piston, a clutch plate pack, and a housing containing the piston and the clutch plate pack. To engage and disengage the piston from the clutch plate set, the system is configured to fill and empty a hydraulic chamber on a hydraulic side of the piston such that hydraulic fluid moves the piston toward and away from the clutch plate set. The piston includes one or more shims or spacer posts forming a flow gap. The piston is also configured to position a seal on the piston closer to the hydraulic side.

Description

Background Technology

[0001] Hydraulic pistons are used in a variety of applications. For example, they are commonly used to actuate clutch plates in vehicle transmissions. The hydraulic pistons in the transmission need to engage and disengage with the clutch plates in a consistent and timely manner. Otherwise, poor performance or even damage may result.

[0002] Therefore, improvements are needed in this area. Summary of the Invention

[0003] A unique hydraulic piston design has been developed that actuates the clutch plates quickly and consistently, addressing other issues. During the transition between the engaged and disengaged states of the clutch plates in the clutch assembly, some piston designs have been found to operate inconsistently and / or slowly. For example, a newer, or intermediate, piston design was developed to simplify piston sealing. During development, this intermediate piston design was found to engage and disengage the clutch assembly too slowly and / or in an unreliable manner compared to older designs. Inconsistent and slow piston operation can affect vehicle performance quality, typically resulting in poor shifting and / or clutch performance.

[0004] After analyzing the performance of earlier piston designs and intermediate piston designs, it was unexpectedly found that the return performance of the hydraulic fluid (such as oil) in the newer intermediate design was worse than that of the older piston design. To actuate or push the piston to engage the clutch plates of the clutch assembly, pressurized hydraulic fluid is supplied to the piston within the cylinder bore of the transmission (or other device) through one or more hydraulic fluid channels. Typically, but not always, the piston is biased by one or more return springs to disengage from the clutch plate assembly. The pressurized hydraulic fluid needs to overcome this spring force to press and clamp the piston onto the clutch plate assembly in this engaged or applied position. To disengage the piston from the clutch plate assembly, hydraulic fluid is discharged through the same hydraulic fluid channels that supplied the hydraulic fluid, and the return spring pushes the piston back into the piston cylinder bore, entering the disengaged state or reaching the disengaged position (i.e., the installed position). In examining the intermediate piston design, it was found that the piston presents a generally flat surface or area at the opening of the hydraulic fluid channel. Essentially, the piston primarily covers the opening to restrict the flow of hydraulic fluid within the cylinder bore during introduction and discharge. In other words, the intermediate piston design was found to reduce the effective area or volume of the cylinder bore.

[0005] In a transmission, the clutch assembly housing or hub defines a cylinder bore in which a piston is slidably disposed. In one form, the piston is annular, and so is the cylinder bore. To enhance hydraulic fluid flow within the piston cylinder bore, the piston includes one or more shims or spacers that form one or more flow gaps along the piston head. The shims separate the piston head from the closed end of the cylinder bore, where openings in the hydraulic fluid passage supply hydraulic fluid to the cylinder bore. During piston retraction, hydraulic fluid can flow through the flow gaps between the shims. When the piston is in the disengaged or mounted position, any hydraulic fluid in the cylinder bore is at a relatively lower pressure compared to when the piston is in the engaged or applied position. When the piston disengages from the clutch plate assembly, a return spring presses the piston shims against the surface of the closed end of the piston cylinder bore. The flow gaps between the shims allow hydraulic fluid to flow freely back into the hydraulic fluid passages. In one form, the shims are positioned to generally prevent obstruction of the openings in the hydraulic fluid passages. The shims are typically aligned with the corresponding walls of the hydraulic fluid passages. By positioning the shim in this manner, hydraulic fluid can flow freely into and out of the piston cylinder bore, promoting a generally laminar flow of the hydraulic fluid. In one configuration, the shim and the corresponding flow clearance are located radially inward on the piston head. It should be recognized that this piston configuration facilitates the free flow of hydraulic fluid, which in turn promotes rapid and consistent actuation of the clutch plate assembly, regardless of temperature or other environmental conditions.

[0006] The piston also includes an inner sealing ring or washer and an outer sealing ring or washer, which slidably seal against the cylinder bore wall. The seals are designed to reduce hydraulic leakage around the piston when hydraulic fluid is pressurized. The piston is constructed such that the sealing rings are recessed as far as possible within the piston cylinder bore, reducing the piston's weight. To reduce weight, the piston head defines a channel between the sealing recesses. The base of the channel is typically flush with the inner surface of the seal. Alternatively, the piston head essentially rises from the base of the channel to provide sufficient material to structurally support the seal. Recessing the piston seals reduces the volume of hydraulic fluid required to actuate the piston, which in turn improves the piston's responsiveness and reliability.

[0007] The systems and technologies described and illustrated in this article involve many unique and innovative aspects. Some of these unique aspects are outlined below, but by no means all.

[0008] Aspect 1 typically involves a system.

[0009] Aspect 2 typically relates to systems described in accordance with any of the preceding aspects, including transmissions.

[0010] Aspect 3 typically relates to systems described in accordance with any of the preceding aspects, including clutch assemblies.

[0011] Aspect 4 typically relates to systems described in any of the preceding aspects, wherein the transmission includes a clutch assembly.

[0012] Aspect 5 generally relates to a system according to any of the preceding aspects, wherein the clutch assembly has a clutch side and a hydraulic side opposite to the clutch side.

[0013] Aspect 6 typically relates to systems described in accordance with any of the preceding aspects, including housings.

[0014] Aspect 7 generally relates to a system according to any of the preceding aspects, wherein the housing defines the cylinder bore.

[0015] Aspect 8 generally relates to a system according to any of the preceding aspects, wherein the housing defines a flow passage to the cylinder bore.

[0016] Aspect 9 generally relates to a system according to any of the preceding aspects, wherein the flow channel is configured to deliver hydraulic fluid.

[0017] Aspect 10 generally relates to a system according to any of the preceding aspects, wherein the flow passage has an opening leading to the cylinder bore.

[0018] Aspect 11 generally relates to a system according to any of the preceding aspects, wherein the flow channel has a channel wall.

[0019] Aspect 12 generally relates to a system according to any of the preceding aspects, wherein the housing includes a clutch drum hub.

[0020] Aspect 13 typically relates to systems described in accordance with any of the preceding aspects, including clutch plate assemblies.

[0021] Aspect 14 generally relates to a system according to any of the preceding aspects, wherein the clutch plate assembly includes one or more reactive plates and one or more friction plates.

[0022] Aspect 15 typically relates to systems described in accordance with any of the preceding aspects, including pistons.

[0023] Aspect 16 generally relates to a system according to any of the preceding aspects, wherein a piston is slidably disposed in a cylinder bore.

[0024] Aspect 17 generally relates to a system according to any of the preceding aspects, wherein the piston is configured to actuate a clutch plate assembly.

[0025] Aspect 18 generally relates to a system according to any of the preceding aspects, wherein the piston has an engaged position in which the piston engages a clutch plate assembly.

[0026] Aspect 19 generally relates to a system according to any of the preceding aspects, wherein the piston has a disengaged position in which the piston is separated from the clutch plate assembly.

[0027] Aspect 20 generally relates to systems described in accordance with any of the preceding aspects, including springs.

[0028] Aspect 21 generally relates to a system according to any of the preceding aspects, wherein a spring contacts a piston.

[0029] Aspect 22 generally relates to a system according to any of the preceding aspects, wherein a spring is configured to bias a piston toward a disengaged position.

[0030] Aspect 23 generally relates to a system according to any of the preceding aspects, wherein a spring is configured to bias a piston toward the hydraulic side.

[0031] Aspect 24 typically relates to a system as described in any of the preceding aspects, wherein the clutch plate assembly is located on the clutch side.

[0032] Aspect 25 typically relates to a system according to any of the preceding aspects, wherein the flow passage is located on the hydraulic side.

[0033] Aspect 26 typically relates to a system according to any of the preceding aspects, in which a piston defines a hydraulic chamber in a cylinder bore.

[0034] Aspect 27 typically relates to systems described in any of the preceding aspects, in which the hydraulic chamber is located on the hydraulic side.

[0035] Aspect 28 generally relates to a system according to any of the preceding aspects, wherein the piston has a head.

[0036] Aspect 29 generally relates to a system according to any of the preceding aspects, wherein the piston has an engaging member extending relative to the head.

[0037] Aspect 30 generally relates to a system according to any of the preceding aspects, wherein the engaging member is configured to engage a clutch plate assembly.

[0038] Aspect 31 generally relates to a system according to any of the preceding aspects, wherein the engagement member is disposed on the clutch side.

[0039] Aspect 32 generally relates to a system according to any of the preceding aspects, wherein the head is positioned on the hydraulic side.

[0040] Aspect 33 generally relates to a system according to any of the preceding aspects, wherein the head includes an inner head and an outer head.

[0041] Aspect 34 generally relates to a system according to any of the preceding aspects, wherein the inner head is disposed radially inward relative to the outer head.

[0042] Aspect 35 generally relates to a system according to any of the preceding aspects, wherein the head defines a groove configured to receive a seal to seal a cylinder bore.

[0043] Aspect 36 generally relates to a system according to any of the preceding aspects, wherein the head is configured to recess the seal toward the hydraulic side.

[0044] Aspect 37 generally relates to systems described in any of the preceding aspects, wherein the seals include gaskets.

[0045] Aspect 38 generally relates to a system according to any of the preceding aspects, wherein the inner head defines an inner recess.

[0046] Aspect 39 generally relates to systems described in any of the preceding aspects, including an inner gasket received in an inner groove.

[0047] Aspect 40 generally relates to a system according to any of the preceding aspects, wherein the inner gasket is configured to seal the cylinder bore.

[0048] Aspect 41 typically relates to a system according to any of the preceding aspects, wherein the outer head defines an outer recess.

[0049] Aspect 42 generally relates to systems described in any of the preceding aspects, including an outer gasket received in an outer recess.

[0050] Aspect 43 generally relates to a system according to any of the preceding aspects, wherein an outer gasket is configured to seal the cylinder bore.

[0051] Aspect 44 generally relates to a system according to any of the preceding aspects, wherein the head of the piston is configured to further recess the inner and outer gaskets into the cylinder bore.

[0052] Aspect 45 typically relates to systems described in any of the preceding aspects, wherein the head defines the channel.

[0053] Aspect 46 typically relates to a system according to any of the preceding aspects, in which the channel is defined between the inner head and the outer head.

[0054] Aspect 47 generally relates to a system according to any of the preceding aspects, wherein the head of the piston is configured to reduce the flow restriction of hydraulic fluid from the flow passage.

[0055] Aspect 48 generally relates to a system according to any of the preceding aspects, wherein the piston is configured to engage and disengage with the clutch plate assembly in a rapid manner.

[0056] Aspect 49 generally relates to a system according to any of the preceding aspects, wherein the piston is configured to engage and disengage from the clutch plate assembly in a consistent manner.

[0057] Aspect 50 generally relates to a system according to any of the preceding aspects, wherein the head has one or more pads extending from the head.

[0058] Aspect 51 generally relates to a system according to any of the preceding aspects, wherein a gasket defines a gap in which one or more hydraulic fluids flow.

[0059] Aspect 52 generally relates to a system as described in any of the preceding aspects, wherein a gasket is positioned in the inner head.

[0060] Aspect 53 generally relates to systems according to any of the preceding aspects, wherein a gasket is aligned with the channel wall of a flow passage to reduce throttling of the hydraulic fluid flow.

[0061] Aspect 54 generally relates to a system according to any of the preceding aspects, wherein the cylinder bore has a cylinder bore bottom wall.

[0062] Aspect 55 generally relates to a system according to any of the preceding aspects, wherein the gasket is configured to contact the bottom wall of the cylinder bore when in the disengaged position.

[0063] Aspect 56 generally relates to a system according to any of the preceding aspects, wherein the joining member has an inner ridge and an outer ridge.

[0064] Aspect 57 generally relates to a system according to any of the preceding aspects, wherein the engaging member defines a cavity between the inner ridge and the outer ridge.

[0065] Aspect 58 generally relates to a system according to any of the preceding aspects, wherein the inner ridge is positioned radially inward relative to the outer ridge.

[0066] Aspect 59 typically relates to a system as described in any of the preceding aspects, wherein the channel has a base plate.

[0067] Aspect 60 generally relates to a system according to any of the preceding aspects, wherein the inner and outer gaskets have surfaces aligned in a planar manner with the base plate of the channel.

[0068] Other forms, objectives, features, aspects, benefits, advantages, and embodiments of the invention will become apparent from the detailed description and accompanying drawings provided herein. Attached Figure Description

[0069] Figure 1 This is a cross-sectional view of the clutch assembly in its separated configuration.

[0070] Figure 2 This is a cross-sectional view of the clutch assembly in its engagement configuration.

[0071] Figure 3 Is Figure 1 A three-dimensional view of the piston found in the clutch assembly.

[0072] Figure 4 yes Figure 3 Side view of the piston on the hydraulic side.

[0073] Figure 5 yes Figure 3 Side view of the piston on the clutch side.

[0074] Figure 6 It is along Figure 5 The line 6-6 in the middle is cut off Figure 3 Cross-sectional view of the piston.

[0075] Figure 7 It is along Figure 6 The middle section 7-7 is cut off Figure 3 Enlarged view of the piston. Detailed Implementation

[0076] To facilitate understanding of the principles of the invention, reference will now be made to the embodiments shown in the accompanying drawings, and they will be described using specific language. However, it should be understood that this is not intended to limit the scope of the invention. Any changes and further modifications to the described embodiments, as well as any further application of the principles of the invention described herein, are contemplated for those skilled in the art to which this invention pertains. One embodiment of the invention is shown in great detail; although it will be apparent to those skilled in the art that some features unrelated to the invention may not be shown for clarity.

[0077] The reference numerals in the following description have been organized to help readers quickly identify the figures that first show various components. In particular, the figure in which an element first appears is usually indicated by the leftmost number in the corresponding reference numeral. For example, an element marked by the "100" series of reference numerals may first appear in... Figure 1 In the figures, elements marked by the "200" series reference numerals may first appear in the figures. Figure 2 And so on.

[0078] refer to Figure 1 Clutch assembly 100 is typically configured to selectively engage a component of a vehicle's powertrain. For example, clutch assembly 100 can engage the output of an engine and / or motor to a transmission, gearbox, and / or other device in the powertrain. Clutch assembly 100 can be used in gasoline-powered vehicles and electric vehicles. In one form, clutch assembly 100 is included in an automatic transmission.

[0079] In the illustrated embodiment, the clutch assembly 100 includes a piston 105, a clutch plate assembly 110, and a hub or housing 115. The housing 115 defines a cylinder bore 117 in which the piston 105 is slidably disposed. The piston 105 and cylinder bore 117 in the depicted example have annular or ring-shaped shapes, and the clutch plate assembly 110 typically has an annular shape. In one embodiment, the piston 105 and / or clutch plate assembly 110 are radially positioned about a hub and / or shaft of the transmission. The piston 105 is configured to selectively engage the clutch plate assembly 110. For example, the clutch plate assembly 110 may mechanically engage individual components of a vehicle's powertrain, allowing selective engagement of these components via the clutch assembly 100. The clutch assembly 100 utilizes hydraulic fluid to move or push the piston 105, thereby actuating the clutch plate assembly 110. In one example, the hydraulic fluid is oil, but other types of fluid may be used in other examples. The housing 115 contains the components of the clutch assembly 100 and the hydraulic fluid. In one example, housing 115 is integrated with housings for another part of a vehicle's powertrain, such as housings for a transmission, motor, and / or engine. Piston 105 and housing 115 are typically made of a rigid material, such as steel, aluminum, and / or another metallic material. Furthermore, the cylinder bore 117 of housing 115 is typically formed to mate at least a portion of piston 105, such that piston 105 and housing 115 fit together within certain tolerances. Within housing 115, clutch plate assembly 110 is positioned relative to piston 105 on clutch side 120. Hydraulic side 125 is defined on the opposite side of clutch side 120 relative to piston 105.

[0080] On the hydraulic side 125 of the clutch assembly 100, piston 105 and housing 115 define a hydraulic chamber 130 in cylinder bore 117. Hydraulic chamber 130 is configured to contain hydraulic fluid. Furthermore, housing 115 defines a hydraulic fluid passage 135 that provides a path for hydraulic fluid to enter and exit hydraulic chamber 130. It can be seen that passage 135 has an opening 136 at cylinder bore 117, and walls 138 surround passage 135. For example, hydraulic fluid can travel from a reservoir, pump, and / or other device containing hydraulic fluid through passage 135 and enter hydraulic chamber 130 through opening 136.

[0081] It should be understood that the housing 115 may be initially cast or otherwise formed to create the cylinder bore 117 and / or channel 135. Alternatively or additionally, the housing 115 may be modified to form the cylinder bore 117 and / or channel 135, for example, by machining, drilling, and / or other techniques. Figure 1In the diagram, piston 105 is shown in either the disengaged or mounted position. In the disengaged position, piston 105 is positioned toward the hydraulic side 125 such that piston 105 does not contact clutch plate assembly 110. When in the disengaged position, hydraulic fluid is at a relatively low pressure within hydraulic chamber 130, or in some cases, hydraulic chamber 130 is partially or completely devoid of hydraulic fluid. By depressurizing the hydraulic fluid in hydraulic chamber 130, the pressure in hydraulic chamber 130 decreases, and piston 105 is biased toward hydraulic side 125 by a return spring, which will be discussed in more detail below.

[0082] At the hydraulic side 125, the piston 105 includes a head 139. The head 139 includes an outer head 140, an inner head 145, and a channel 150 defined between the outer head 140 and the inner head 145. In the illustrated embodiment, the piston 105 is integrally formed such that the outer head 140 and the inner head 145 are parts of the same piece of material. In one form, the channel 150 is formed in the head 139 by casting and / or machining, but the channel 150 can be formed in other ways. The outer head 140 is positioned radially outward from the inner head 145. At the hydraulic side 125, the head 139 has a spacer post in the form of a gasket 152 extending from the inner head 145, which is configured to contact the bottom wall 154 of the cylinder bore 117 at the hydraulic side 125 when the piston 105 is in the disengaged position. It can be seen that at the hydraulic side 125, the gasket 152 on the inner head 145 extends higher than the surface of the outer head 140. The outer head 140 and the inner head 145 can be shaped in such a way as to facilitate the rapid and consistent flow of hydraulic fluid into and / or out of the hydraulic chamber 130.

[0083] like Figure 1 As shown, channel 150 is located on the hydraulic side 125 of piston 105, and channel 150 is recessed towards clutch side 120. Channel 150 has a base plate 155, and walls 157 are positioned on opposite sides of channel 150. It can be seen that the wall 157 along the gasket 152 at the inner head 145 is generally aligned with the wall 138 of channel 135. This alignment reduces obstruction of hydraulic fluid flow through opening 136 of channel 135, thereby reducing throttling of fluid flow.

[0084] As shown, piston 105 defines an outer recess 160 and an inner recess 165. The outer recess 160 is located on the outer head 140 and opens radially outward. Similarly, the inner recess 165 is located on the inner head 145 and opens radially inward. The outer recess 160 is configured to retain an outer washer 170, and the inner recess 165 is configured to retain an inner washer 175. The outer and inner washers 170 and 175 are configured to fill the gap between piston 105 and housing 115. By filling the gap, the outer and inner washers 170 and 175 are configured to form a seal between hydraulic chamber 130 and clutch plate assembly 110 to prevent the flow of hydraulic fluid. The outer and inner washers 170 and 175 may include one or more types of gasket members. It should be appreciated that the radial position of the components can be reversed. In one example, piston 105 is inverted, such that... Figure 1 In the example, the inner head 145 is positioned radially outward from the outer head 140. In another example, Figure 1 In the example, the outer washer 170 and the inner washer 175 are arranged such that the inner washer 175 is positioned radially outward from the outer washer 170.

[0085] The clutch assembly 100 is designed such that the outer washer 170 and inner washer 175 are recessed as far as possible into the cylinder bore 117, thereby minimizing the volume of the hydraulic chamber 130, which in turn improves performance. A smaller volume of hydraulic fluid is required to actuate or push the piston 105. It can be seen that the surfaces of the outer washer 170 and inner washer 175 facing the hydraulic side 125 are generally aligned flush or planar with the base plate 155 of the channel 150. In other words, portions of the outer head 140 and inner head 145 are bent toward the hydraulic side 125 such that the outer recess 160 and inner recess 165 for the outer washer 170 and inner washer 175 are properly supported by sufficient material in the head 139 of the piston 105. The channel 150 in the head 139 helps reduce the amount of material used and the overall weight of the piston 105, which in turn helps improve the responsiveness of the clutch assembly 100.

[0086] The clutch assembly 100 also includes a return spring 180, which is positioned on the clutch side 120 relative to the piston 105. The return spring 180 is configured to bias the piston 105 to... Figure 1 The shown separation or installation position. When hydraulic fluid leaves the hydraulic chamber 130, the return spring 180 provides a force in the direction toward the hydraulic side 125, causing the piston 105 to move away from the clutch plate assembly 110. For example, the return spring 180 can apply a force to the piston 105, causing the gasket 152 to contact the cylinder bore bottom wall 154 on the hydraulic side 125.

[0087] refer to Figure 2When piston 105 compresses clutch plate assembly 110, clutch assembly 100 is in an engaged configuration or position. In the engaged state, hydraulic fluid 201, such as oil, in hydraulic chamber 130 exerts force on piston 105 and return spring 180. Piston 105 then presses clutch plate assembly 110. A pump and / or another device can force hydraulic fluid 201 through passage 135 to fill and pressurize hydraulic chamber 130. Similar to release piston 105, passage 150 can support reliable and rapid operation of piston 105 when piston 105 is engaged. For example, the shape, position, surface, and / or other characteristics of piston 105 compared to earlier designs allow hydraulic fluid 201 to fill hydraulic chamber 130 more quickly and / or in a more desirable manner.

[0088] In the example shown, piston 105 includes an engagement member 202 having an outer ridge 205 and an inner ridge 210. The outer ridge 205 is positioned on the radially outward portion of the engagement member 202 of piston 105 and toward the clutch side 120. Similarly, the inner ridge 210 is positioned on the radially inward portion of the engagement member 202 and toward the clutch side 120. As shown, piston 105 contacts clutch plate assembly 110 via engagement member 202 (i.e., via outer ridge 205 and inner ridge 210). Piston 105 also defines a cavity 215 between the outer ridge 205 and the inner ridge 210. Cavity 215 opens toward the clutch side 120. In one embodiment, cavity 215 reduces the weight of piston 105 without significantly reducing the strength and / or stiffness of piston 105 compared to a solid piston 105.

[0089] As shown in the figure, the clutch plate assembly 110 includes at least one friction plate 220 and at least one reactive plate 225. The friction plate 220 is configured to provide friction between the reactive plates 225. When the piston 105 contacts the clutch plate assembly 110, the friction plate 220 and the reactive plate 225 are mechanically engaged by friction. As previously described, the clutch plate assembly 110 allows components of the vehicle's powertrain to be selectively engaged and disengaged by the piston 105 from the clutch plate assembly 110.

[0090] Figure 3 , Figure 4 and Figure 5A complete view of a single piston 105 is shown. As shown, piston 105 is annular and defines a powertrain opening 305 in its radially inward portion. When piston 105 is mounted in clutch assembly 100, one or more components of the vehicle's powertrain, such as wheel hubs, can be positioned within the powertrain opening 305. Furthermore, piston 105 extends fully circumferentially around the powertrain opening 305. In one form, piston 105 is made of a rigid material such that piston 105 retains its shape under pressure from hydraulic fluid. For example, piston 105 can be made of steel, aluminum, and / or other metals. In one embodiment, piston 105 is formed from a mold casting and / or using machining to shape piston 105. In another embodiment, piston 105 is 3D printed to form the desired shape of channel 150.

[0091] Channel 150 extends along the entire circumference of piston 105. The shape of channel 150 remains unchanged along the circumference. Similarly, the shape of outer head 140 remains unchanged along the circumference of piston 105. In other variations, channel 150 is discontinuous, forming discrete arcs along head 139.

[0092] In some cases, the inner head 145 is not necessarily consistent around the circumference. In the example shown, the inner head 145 includes multiple gaskets 152 positioned at multiple points circumferentially. The gaskets 152 may be integrally formed with the inner head 145 and the entire piston 105. Due to the gaskets 152, the shape of the inner head 145 varies around the circumference of the piston 105. Furthermore, the cavity 215 is not necessarily consistent around the circumference. As shown, the shape of the cavity 215 varies around the circumference of the piston 105. For example, the cavity 215 includes support features that facilitate casting and / or forming the piston 105 in another manner. It should be understood that the gaskets 152 may be positioned at different points on the piston 105, the circumference of the piston 105 may include additional discontinuous features, and / or the shape of the piston 105 may vary around the circumference in various other ways.

[0093] In the example shown, gaskets 152 are circumferentially spaced around piston 105. Gaskets 152 define one or more flow gaps 310. Gap 310 facilitates contact between the entire surface of the head 139 of piston 105 and hydraulic fluid 201. The larger exposed surface area provided by the gaps 310 contributes to improved responsiveness of piston 105.

[0094] refer to Figure 6 and Figure 7 The cross-sectional view of piston 105 depicts Figure 1 and Figure 2 Similar features to the piston 105 shown. However, Figure 6 and Figure 7The cross section in the diagram shows the relationship with Figure 1 and Figure 2 The cross-section of the inner head 145 is different. Figure 6 and Figure 7 The cross-section of the inner head 145 does not include the gasket 152. In other words, this cross-section is taken at the gap 310 located between the gaskets 152. As shown, the wall 157 of the channel 150 smoothly transitions to the base plate 155 in a curved manner.

[0095] refer to Figure 1 , Figure 2 , Figure 3 , Figure 6 and Figure 7 The gasket 152, in conjunction with the flow clearance 310 on the piston 105, provides a larger area for the hydraulic fluid 201 to flow to the head 139 of the piston 105. The design of the clutch assembly 100 facilitates reduced throttling of the hydraulic fluid 201 as the piston 105 moves between the engaged and disengaged positions. Compared to previous designs, the hydraulic fluid 201 can flow into and out of the hydraulic chamber 130 more quickly and consistently. By employing the illustrated design, the performance of the piston 105 is highly reliable and consistent during the transition between the engaged and disengaged states.

[0096] During actuation of piston 105, clutch assembly 100 fills or pressurizes hydraulic chamber 130 with hydraulic fluid 201. As previously described, hydraulic fluid 201 flows from a pump and / or reservoir and through passage 135. When hydraulic fluid 201 fills hydraulic chamber 130, it applies force to piston 105 to compress return spring 180. Piston 105 moves toward clutch side 120 to compress clutch plate assembly 110. Piston 105 and clutch plate assembly 110 are then engaged or in a specific position.

[0097] When piston 105 disengages from clutch plate assembly 110, clutch assembly 100 discharges hydraulic fluid 201 from hydraulic chamber 130 through passage 135. Return spring 180 pushes piston 105 against hydraulic side 125 of cylinder bore 117. As hydraulic fluid 201 exits hydraulic chamber 130, its flow through opening 136 of passage 135 is generally unobstructed. Due to the configuration of the depicted clutch assembly 100, hydraulic fluid 201 can flow rapidly and / or uniformly into passage 135.

[0098] Piston 105 is configured to repeatedly perform the operation with the same level of mass. Specifically, piston 105 and the hydraulic device are configured to perform nearly identical operations during multiple strokes of piston 105. In one example, piston 105 can repeatedly discharge most or all of the hydraulic fluid 201 from hydraulic chamber 130 within a certain time period. For example, at least 90% of the hydraulic fluid can leave hydraulic chamber 130 within one second. In another example, piston 105 can repeatedly discharge hydraulic fluid at a constant or near-constant rate until a certain amount of hydraulic fluid has left hydraulic chamber 130. For example, 90% of the hydraulic fluid can leave hydraulic chamber 130 at a constant rate. In another instance, the rate fluctuation is less than 10% until at least 90% of the hydraulic fluid has left hydraulic chamber 130.

[0099] Piston 105 is further configured to operate consistently under different environmental conditions. In one example, piston 105 can operate continuously at different operating temperatures, such as 20, 40, and 80 degrees Celsius. For example, piston 105 can discharge all or almost all of the hydraulic fluid from hydraulic chamber 130 at multiple temperatures within the same time period, and / or piston 105 can discharge hydraulic fluid at a constant or nearly constant rate at multiple temperatures. The performance of piston 105 is repeatable, ensuring that the quality of clutch engagement and disengagement is consistent across multiple instances.

[0100] Glossary The language used in the claims and description shall have only its ordinary and common meaning, except where expressly defined below. The words in these definitions shall have only their ordinary and common meaning. This ordinary and common meaning encompasses all consistent dictionary definitions found in the most recently published Webster's Dictionary and the Random House Dictionary. As used in the description and claims, the following definitions apply to these terms and their common variations listed below.

[0101] "And / or" is typically a grammatical conjunction indicating that one or more of the conditions it connects may occur. For example, it can mean one or both of the two conditions mentioned above may occur. Generally, "and / or" includes any combination of the listed sets. For example, "X, Y, and / or Z" includes: any single letter (e.g., {X}, {Y}, {Z}); any combination of two letters (e.g., {X, Y}, {X, Z}, {Y, Z}); and all three letters (e.g., {X, Y, Z}). Such combinations may also include other elements not listed.

[0102] A "cylinder bore" typically refers to a long, hollow channel in a mechanical component or other object. Usually, but not always, a cylinder bore has a cylindrical shape. In one form, a cylinder bore is typically formed by the rotational or torsional motion of a tool (such as a drilling machine), but cylinder bores can be formed in other ways.

[0103] A "cavity" typically refers to an empty space within a solid object. A cavity can be completely or partially surrounded by a solid object. For example, a cavity can be connected to its surrounding environment.

[0104] A "channel" usually refers to a narrow groove on the surface of an object.

[0105] "Circumferential uninterrupted loop" here refers to a portion or surface of any shape with a continuously closed boundary. It can be circular or non-circular, including meandering around various openings, elements, or obstacles.

[0106] A "clutch" generally refers to a device that engages and disengages a mechanical power transmission between two or more rotating shafts or other moving parts. While the motion involved is typically rotary, linear clutches are also used to engage and disengage parts that move in a linear or near-linear motion. For example, clutch components can be engaged and disengaged by mechanical, hydraulic, and / or electrical actuation. Clutches can include engagement clutches and friction clutches. Wet clutches are typically immersed in a cooling lubricant or other liquid, while dry clutches are not. Some non-limiting examples of clutches include conical clutches, centrifugal clutches, torque limiter clutches, axial clutches, disc clutches, claw clutches, and flange clutches, to name just a few.

[0107] "Flow" generally refers to the movement of a fluid. In some cases, fluid flow is contained within a channel or other space defined by one or more solid objects. For example, fluid flow can be contained within a pipe, vent, hose, container, space defined between multiple objects, and / or another space. Typically, fluid flow is contained such that the fluid is guided along a desired path in a desired direction. The flow direction at a point is the overall direction in which the various parts of the fluid move at that point. For example, the flow direction might be the average of the directions in which different parts of the fluid body move. In one example, the fluid may flow in a smooth laminar manner, such that all or almost all of the fluid body flows in the same overall direction. In another example, the fluid may flow in a turbulent manner, where one or more parts of the fluid body recirculate, swirl, move randomly, and / or move in another manner against the usual direction of flow.

[0108] "Fluid" generally refers to a substance that does not have a fixed shape. For example, fluids include liquids and / or gases. Typically, fluids are easily flowable; for example, air flows over an airplane wing, blood flows in a circulatory system, water flows in pipes, or oil flows in a motor. In some cases, a fluid refers to a mixture of solids, liquids, and / or gases. For example, a slurry of solids and water, droplets mixed with air, aerated solid particles, mixtures of solids with liquids and gases, and / or mixtures of other different materials can all be fluids.

[0109] "Gasket component" here refers to an object designed to seal the joint between two surfaces. Gasket components can be of various shapes, such as, but not limited to, circular, square, or hexagonal. Gasket components can be made of any material that effectively seals the joint between two materials, such as rubber, plastic, or other types of polymers. It can be single or multi-material. It can be made of one material or more materials.

[0110] "Casing" generally refers to a component that covers, protects, or supports another object. For example, the casing of a desktop computer is its outer casing component, which can be made of various materials to protect the internal components.

[0111] "Hydraulic fluid" generally refers to a fluid used to transmit power in various devices. Hydraulic fluids are used in devices such as brakes, power steering, transmissions, and industrial machinery, to name just a few. Typically, but not always, hydraulic fluids are incompressible. In other words, when the pressure on the fluid changes, its volume does not change. Hydraulic fluids can be water-based and / or oil-based. For example, a hydraulic fluid can be an oil, such as mineral oil. In some cases, hydraulic fluids serve secondary purposes, such as lubricating and / or cooling moving parts of a device.

[0112] "One-piece molding" typically refers to components and / or multiple components that are fused into a single piece. One-piece molded components cannot be disassembled without compromising their integrity.

[0113] "Metallic" generally refers to materials that contain metals or are predominantly (50% or more by weight) metals. Metallic materials can be a single pure metal, an alloy of two or more metals, or any other suitable combination of metals. The term can also be used to refer to materials that include non-metallic substances. For example, a metallic cable may include one or more strands of conductor, primarily copper coated in a polymer or other non-conductive material.

[0114] An "opening" usually refers to a space or hole through which something can pass.

[0115] A "power system" generally refers to a device and / or system for converting stored energy into kinetic energy for propulsion purposes. A power system may include multiple power sources and can be used in non-wheeled vehicles. By way of non-limiting examples, the stored energy may include chemical, solar, nuclear, electrical, electrochemical, kinetic, and / or other potential energy sources. For example, a power system of a motor vehicle includes devices that generate power and deliver that power to a road surface, water, and / or air. These devices in a power system include engines, electric motors, transmissions, driveshafts, differentials, and / or final drive components (e.g., drive wheels, continuous tracks, propellers, thrusters, etc.).

[0116] "Radially outward" typically refers to a relative position at a greater distance from a defined center point or axis. If an object has a starting point at a given distance from a defined center or axis and then moves further away from that center point or axis, the object can extend radially outward.

[0117] A "spring" generally refers to an elastic object that stores mechanical energy. A spring may include a resilient mechanism that can be pressed, pulled, and / or twisted, but returns to its original shape when released. Springs may be made of resilient or elastic materials, such as metals and / or plastics. Springs can resist or withstand a variety of loads and apply a constant or variable level of force. For example, springs may include tension springs, compression springs, torsion springs, constant springs, and / or variable springs. Springs may take many forms, such as flat springs, machined springs, and / or serpentine springs. By way of non-limiting examples, springs may include various helical springs, pocket springs, Bonnell coils, bias coils, continuous coils, cantilever springs, spiral springs, thin springs, leaf springs, V-springs, gas springs, leaf blade springs, torsion springs, rubber bands, spring washers, and / or wave springs, to name just a few.

[0118] A "transmission" generally refers to a power system that provides mechanical power to a controlled application. Transmissions use gears and / or gear trains to provide speed, direction, and / or torque conversion from a rotational power source to another device.

[0119] "Turbulence" generally refers to the chaotic, unstable, and / or non-uniform nature of fluid motion. For example, a flow can be turbulent when parts of a fluid recirculate, swirl, move randomly, and / or move in an alternative direction against the usual flow direction. Turbulence increases when more parts of the fluid move erratically and / or when the velocity of the erratic parts of the fluid increases. Turbulence is caused by pressure changes and / or physical disturbances in the flow of a fluid. For example, the shape of an object in the flow path of a fluid can disturb the flow and cause it to become turbulent.

[0120] It should be noted that, unless otherwise explicitly discussed, singular articles (“a,” “an,” “the,” etc.) used in the specification and / or claims include plural forms. For example, if the specification and / or claims refer to “an apparatus” or “the apparatus,” it includes one or more such apparatuses.

[0121] It should be noted that directional terms, such as “upward,” “downward,” “top,” “bottom,” “lateral,” “longitudinal,” “radial,” “circumferential,” “horizontal,” “vertical,” etc., are used herein only to facilitate the reader’s understanding of the illustrated embodiments, and their use in any way is not intended to limit the described, illustrated, and / or claimed features to a particular direction and / or orientation.

[0122] While the invention has been illustrated and described in detail in the accompanying drawings and the foregoing description, the drawings and the foregoing description should be considered illustrative rather than restrictive. It should be understood that only preferred embodiments have been shown and described, and protection is intended for all variations, equivalents, and modifications falling within the spirit of the invention as defined by the following claims. All publications, patents, and patent applications referenced in this specification are incorporated herein by reference, just as each individual publication, patent, or patent application is expressly and individually indicated by reference and is fully set forth herein.

[0123] Figure Labels 100 Clutch Assembly 105 Piston 110 Clutch Plate Assembly 115 Outer shell 117 Cylinder Bore 120 Clutch side 125 Hydraulic side 130 hydraulic chamber 135 channels 136 Opening 138 wall 139 Head 140 External head 145 Inner head 150 channels 152 gasket 154 Cylinder Bore Bottom Wall 155 base plate 157 wall 160 External Groove 165 Inner Groove 170 outer washer 175 Inner Washer 180° return spring 201 Hydraulic Fluid 202 Jointing Components 205 External ridge 210 Inner spine 215 Cavity 220 friction plate 225 reaction tablets 305 Powertrain System Opening 310 gap

Claims

1. A system comprising: Clutch assembly, including Clutch plate assembly, The outer casing defines the cylinder bore. The piston is slidably disposed in the cylinder bore. The piston is configured to actuate the clutch plate assembly. The piston described herein has a head, and The head has one or more pads extending from it.

2. The system according to claim 1, further comprising: The outer casing defines a flow passage to the cylinder bore; The flow channel is configured to deliver hydraulic fluid; as well as The head of the piston is configured to reduce flow restriction of the hydraulic fluid from the flow passage.

3. The system of claim 2, wherein the gasket defines one or more gaps through which the hydraulic fluid flows.

4. The system according to claim 3, wherein: The head includes an inner head and an outer head; The inner head is radially inward relative to the outer head; and The gasket is positioned on the inner head.

5. The system according to claim 2, wherein: The flow channel has an opening leading to the cylinder bore; The flow channel has a channel wall; and The gasket is aligned with the channel wall of the flow channel to reduce the flow throttling of the hydraulic fluid.

6. The system according to claim 2, wherein: The piston has an engagement position where it engages the clutch plate assembly. The piston has a disengaged position, at which the piston is separated from the clutch plate assembly; The cylinder bore has a bottom wall; as well as The gasket is configured to contact the bottom wall of the cylinder bore when it is in the separated position.

7. The system according to claim 6, further comprising: A spring is configured to bias the piston to the disengaged position.

8. The system according to claim 1, wherein: The clutch assembly has a clutch side and a hydraulic side positioned opposite to the clutch side; The head defines a groove, which is configured to receive a seal to seal the cylinder bore; The head is configured to recess the seal toward the hydraulic side; as well as The seal includes a gasket.

9. The system according to claim 1, wherein: The head includes an inner head and an outer head; and The inner head is arranged radially inward relative to the outer head.

10. The system according to claim 9, further comprising: The inner head defines an inner groove; The inner washer is received within the inner groove; The inner gasket is configured to seal the cylinder bore; The outer head defines an outer groove; The outer washer is received within the outer groove; The outer gasket is configured to seal the cylinder bore; and The head of the piston is configured to further recess the inner and outer gaskets into the cylinder bore.

11. The system according to claim 10, wherein: The head-defined channel; and The channel is defined between the inner head and the outer head.

12. The system according to claim 1, wherein: The piston has a engagement member extending opposite to the head; and The engagement member is configured to engage the clutch plate assembly.

13. The system according to claim 12, wherein: The connecting member has an inner ridge and an outer ridge; The inner ridge is positioned radially inward relative to the outer ridge; and The connecting member defines a cavity between the inner ridge and the outer ridge.

14. The system according to claim 1, wherein: The outer casing defines a flow channel to the cylinder bore; The piston has an engagement position where it engages the clutch plate assembly. The piston has a disengaged position, at which the piston is separated from the clutch plate assembly; The head includes an inner head and an outer head; The inner head is arranged radially inward relative to the outer head; The head-defined channel; The channel is defined between the inner head and the outer head; The gasket defines one or more gaps through which the hydraulic fluid flows; The cylinder bore has a bottom wall; The gasket is configured to contact the bottom wall of the cylinder bore when it is in the separated position; The flow channel is configured to both supply hydraulic fluid to and discharge hydraulic fluid from the cylinder bore; The bottom wall of the cylinder bore faces the head of the piston; The gasket extends from the inner head to form a spacer post; The inner head and the outer head each have a surface facing the bottom wall of the cylinder bore, and the surfaces are flush with each other. as well as The gasket extends further from the surface of the inner head towards the bottom wall of the cylinder bore than the surface of the outer head.

15. The system according to claim 14, wherein: The channel has a bottom plate and walls extending from opposite sides of the bottom plate; The wall of the channel along the gasket at the inner head is aligned with the channel wall of the flow channel; The bottom wall of the cylinder bore defines the opening of the flow channel into the cylinder bore; as well as The flow channel has a channel wall at the opening on the bottom wall of the cylinder bore.

16. A system comprising: Clutch assembly, including The outer casing defines the cylinder bore; Clutch plate assembly, A piston is configured to actuate the clutch plate assembly, wherein the piston has a head, wherein the head includes an inner head and an outer head, wherein the piston has an engaged position in which the piston engages the clutch plate assembly, and wherein the piston has a disengaged position in which the piston disengages from the clutch plate assembly. A spring is configured to bias the piston to the disengaged position; The head of the piston is configured to further recess the inner and outer gaskets into the cylinder bore. The inner head defines an inner groove; The inner washer is received in the inner groove; The inner gasket is configured to seal the cylinder bore; The outer head defines an outer groove; The outer washer is received in the outer groove, and The outer gasket is configured to seal the cylinder bore.

17. The system of claim 16, wherein the head defines a channel, the channel being defined between the inner head and the outer head.

18. The system according to claim 17, wherein: The channel has a base plate; and The inner washer and the outer washer have surfaces that are aligned with the bottom plate of the channel in a planar manner.

19. The system according to claim 16, wherein: The outer casing defines a flow channel to the cylinder bore; The flow channel is configured to deliver hydraulic fluid; and The head of the piston is configured to reduce flow restriction of the hydraulic fluid from the flow passage.

20. The system of claim 19, wherein: The head has one or more pads extending from the head; and The gasket defines one or more gaps through which the hydraulic fluid flows.

21. The system of claim 16, wherein the inner washer and the outer washer overlap axially in a direction orthogonal to the rotation axis of the clutch assembly.

22. The system according to claim 16, wherein: The head-defined channel; The channel is defined between the inner head and the outer head; The outer casing defines a flow channel to the cylinder bore; The clutch assembly has a clutch side and a hydraulic side positioned opposite to the clutch side; The clutch plate assembly is positioned on the clutch side; The flow channel is located on the hydraulic side; The channel has a bottom plate and walls extending from opposite sides of the bottom plate; The outer washer and the inner washer have surfaces facing the hydraulic side; as well as The surfaces of the outer washer and the inner washer are aligned with the bottom plate of the channel in a planar manner.

23. The system of claim 22, wherein the inner head and the outer head are each bent from the bottom plate of the channel toward the hydraulic side to provide material for supporting the inner groove of the inner washer and the outer groove of the outer washer.

24. The system according to any one of claims 1 to 23, further comprising: The outer casing defines a flow passage to the cylinder bore; The flow channel is configured to deliver hydraulic fluid; as well as The head of the piston is configured to reduce flow restriction of the hydraulic fluid from the flow channel.

25. The system according to any one of claims 1 to 24, wherein the gasket defines one or more gaps through which the hydraulic fluid flows.

26. The system according to any one of claims 1 to 25, wherein: The head includes an inner head and an outer head; The inner head is radially inward relative to the outer head; and The gasket is positioned on the inner head.

27. The system according to any one of claims 1 to 26, wherein: The flow channel has an opening leading to the cylinder bore; The flow channel has a channel wall; and The gasket is aligned with the channel wall of the flow channel to reduce the flow throttling of the hydraulic fluid.

28. The system according to any one of claims 1 to 27, wherein: The piston has an engagement position where it engages the clutch plate assembly. The piston has a disengaged position, at which the piston is separated from the clutch plate assembly; The cylinder bore has a bottom wall; as well as The gasket is configured to contact the bottom wall of the cylinder bore when it is in the separated position.

29. The system according to any one of claims 1 to 28, further comprising: A spring is configured to bias the piston to the disengaged position.

30. The system according to any one of claims 1 to 29, wherein: The clutch assembly has a clutch side and a hydraulic side positioned opposite to the clutch side; The head defines a groove, which is configured to receive a seal to seal the cylinder bore; The head is configured to recess the seal toward the hydraulic side; as well as The seal includes a gasket.

31. The system according to any one of claims 1 to 30, wherein: The head includes an inner head and an outer head; and The inner head is arranged radially inward relative to the outer head.

32. The system according to any one of claims 1 to 31, further comprising: The inner head defines an inner groove; The inner washer is received within the inner groove; The inner gasket is configured to seal the cylinder bore; The outer head defines an outer groove; The outer washer is received within the outer groove; The outer gasket is configured to seal the cylinder bore; and The head of the piston is configured to further recess the inner and outer gaskets into the cylinder bore.

33. The system according to any one of claims 1 to 32, wherein: The head-defined channel; and The channel is defined between the inner head and the outer head.

34. The system according to any one of claims 1 to 33, wherein: The piston has a engagement member extending opposite to the head; and The engagement member is configured to engage the clutch plate assembly.

35. The system according to any one of claims 1 to 34, wherein The connecting member has an inner ridge and an outer ridge; The inner ridge is positioned radially inward relative to the outer ridge; and The connecting member defines a cavity between the inner ridge and the outer ridge.

36. The system according to any one of claims 1 to 35, wherein The outer casing defines a flow channel to the cylinder bore; The piston has an engagement position where it engages the clutch plate assembly. The piston has a disengaged position, at which the piston is separated from the clutch plate assembly; The head includes an inner head and an outer head; The inner head is arranged radially inward relative to the outer head; The head-defined channel; The channel is defined between the inner head and the outer head; The gasket defines one or more gaps through which the hydraulic fluid flows; The cylinder bore has a bottom wall; The gasket is configured to contact the bottom wall of the cylinder bore when it is in the separated position; The flow channel is configured to both supply hydraulic fluid to and discharge hydraulic fluid from the cylinder bore; The bottom wall of the cylinder bore faces the head of the piston; The gasket extends from the inner head to form a spacer post; The inner head and the outer head each have a surface facing the bottom wall of the cylinder bore, and the surfaces are flush with each other. as well as The gasket extends further from the surface of the inner head towards the bottom wall of the cylinder bore than the surface of the outer head.

37. The system according to any one of claims 1 to 36, wherein: The channel has a bottom plate and walls extending from opposite sides of the bottom plate; The wall of the channel along the gasket at the inner head is aligned with the channel wall of the flow channel; The bottom wall of the cylinder bore defines the opening of the flow channel into the cylinder bore; as well as The flow channel has a channel wall at the opening on the bottom wall of the cylinder bore.

38. The system according to any one of claims 1 to 37, wherein the head defines a channel, the channel being defined between the inner head and the outer head.

39. The system according to any one of claims 1 to 38, wherein: The channel has a base plate; and The inner washer and the outer washer have surfaces that are aligned with the bottom plate of the channel in a planar manner.

40. The system according to any one of claims 1 to 39, wherein: The outer casing defines a flow channel to the cylinder bore; The flow channel is configured to deliver hydraulic fluid; as well as The head of the piston is configured to reduce flow restriction of the hydraulic fluid from the flow passage.

41. The system according to any one of claims 1 to 40, wherein: The head has one or more pads extending from the head; and The gasket defines one or more gaps through which the hydraulic fluid flows.

42. The system according to any one of claims 1 to 41, wherein the inner washer and the outer washer overlap axially in a direction orthogonal to the rotation axis of the clutch assembly.

43. The system according to any one of claims 1 to 42, wherein: The head-defined channel; The channel is defined between the inner head and the outer head; The outer casing defines a flow channel to the cylinder bore; The clutch assembly has a clutch side and a hydraulic side positioned opposite to the clutch side; The clutch plate assembly is positioned on the clutch side; The flow channel is located on the hydraulic side; The channel has a bottom plate and walls extending from opposite sides of the bottom plate; The outer washer and the inner washer have surfaces facing the hydraulic side; as well as The surfaces of the outer washer and the inner washer are aligned with the bottom plate of the channel in a planar manner.

44. The system according to any one of claims 1 to 43, wherein the inner head and the outer head are each bent from the bottom plate of the channel toward the hydraulic side to provide material for supporting the inner groove of the inner washer and the outer groove of the outer washer.

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