# US 2019/0170030 A1 · Variable cam timing phaser utilizing hydraulic logic element

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2019/0170030 A1
- Document ID: US20190170030A1
- Status: Published application
- Kind: A1
- Application number: 16/306,660
- Filed: 2017-05-10
- Published: 2019-06-06
- Earliest claimed: 2016-06-08
- Assignees: Scania CV AB
- Applicants: Scania CV AB
- Inventors: Daniel OLOVSSON; Mikael ERIKSSON
- Web page: https://patentgrep.com/patent/US20190170030A1

## CPC

- F01L 1/34409: {by torque-responsive means}
- F01L 1/3442: {using hydraulic chambers with variable volume to transmit the rotating force}
- F01L 2001/34426: {Oil control valves}
- F01L 2001/34483: {Phaser return springs}
- F01L: CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES

## Abstract

A variable cam timing phaser arrangement is disclosed, comprising: a rotor having at least one vane; a stator co-axially surrounding the rotor, having at least one recess for receiving the at least one vane of the rotor, wherein the at least one vane divides the at least one recess into a first chamber and a second chamber; and a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa. The control assembly comprises a cam torque actuation control valve comprising a valve body and a hydraulic shuttle element. The HSE shuttles between two positions in response to overpressure in the first or second chamber, which prevents flow between the chambers. Deploying a blocking device blocks the HSE from attaining one of the two positions, thereby allowing unidirectional flow between the two chambers. By timing the deployment of the blocking device, the direction of flow can be controlled.

## Claims

### Claim 1

A variable cam timing phaser arrangement for an internal combustion engine comprising:
a rotor having at least one vane, the rotor arranged to be connected to a camshaft;
a stator co-axially surrounding the rotor, having at least one recess for receiving the at least one vane of the rotor and allowing rotational movement of the rotor with respect to the stator, the stator having an outer circumference arranged for accepting drive force;
wherein the at least one vane divides the at least one recess into a first chamber and a second chamber, the first chamber and the second chamber being arranged to receive hydraulic fluid under pressure, wherein the introduction of hydraulic fluid into the first chamber causes the rotor to move in a first rotational direction relative to the stator and the introduction of hydraulic fluid into the second chamber causes the rotor to move in a second rotational direction relative to the stator, the second rotational direction being opposite the first rotational direction; and
a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa, wherein the control assembly comprises:
a cam torque actuation control valve located centrally within the rotor and/or camshaft, the CTA control valve comprising a valve body having a first port arranged in fluid communication with the first chamber, a second port arranged in fluid communication with the second chamber, and a hydraulic shuttle element arranged in the valve body; and
a blocking device arranged in conjunction with the valve body;
wherein the hydraulic shuttle element is configured to be moved in a first direction to a first closed position by overpressure in the first chamber and moved in the second direction to a second closed position by overpressure in the second chamber;
whereby in the first closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the first chamber to the second chamber; and
whereby in the second closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the second chamber to the first chamber; and
wherein the blocking device comprises at least one blocking element that is deployable between a disengaged position and an engaged position, wherein the at least one blocking element is in the engaged position configured to prevent the hydraulic shuttle element from moving to the first closed position or the second closed position depending on the position of the hydraulic shuttle element when the blocking device is deployed, whereby the hydraulic shuttle element is configured to move either between the first closed position in response to overpressure in the first chamber and a second open position in response to overpressure in the second chamber, or between the second closed position in response to overpressure in the second chamber and a first open position in response to overpressure in the first chamber;
whereby in the second open position the hydraulic shuttle element allows fluid flow from the second chamber to the first chamber; and
whereby in the first open position the hydraulic shuttle element allows fluid flow from the first chamber to the second chamber.

### Claim 2 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the hydraulic shuttle element is arranged to move by translational motion along a longitudinal axis of the valve body in response to pressure differences between the first chamber and the second chamber.

### Claim 3 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the CTA control valve comprises:
a valve body having the first port arranged at a first end of the valve body and the second port arranged at a second end of the valve body, wherein a first valve seat is arranged in the valve body between the first end and a middle portion of the body, and a second valve seat is arranged in the valve body between the middle portion of the body and the second end; and
a hydraulic shuttle element comprising a first valve member arranged between the first end and the first valve seat, and arranged to be able to form a seal with the first valve seat, a second valve member arranged between the second valve seat and the second end and arranged to be able to form a seal with the second valve seat, and a valve stem passing through the first valve seat and second valve seat and arranged to attach the first valve member to the second valve member, wherein the valve stem has a length such that when the first valve member forms a seal with the first valve seat the second valve member cannot be seated on the second valve seat, and vice-versa when the second valve member forms a seal with the second valve seat the first valve member cannot be seated on the first valve seat.

### Claim 4 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the blocking device comprises:
a cylinder having a first end in fluid communication with the first chamber and a second end in fluid communication with the second chamber;
a cylinder member arranged in the cylinder and arranged to be moveable in a direction along a longitudinal axis of the cylinder between a first cylinder position by fluid pressure whenever the hydraulic shuttle element is in a first closed position, and a second cylinder position by fluid pressure whenever the hydraulic shuttle element is in a second closed position, wherein the cylinder member is arranged to be moveable in a radial direction relative to the longitudinal axis of the cylinder when in the first cylinder position or second cylinder position whenever the blocking device is deployed;
a first blocking element arranged to be moveable to an engaged position by the radial motion of the cylinder member whenever the blocking device is deployed with the cylinder member in the second position, wherein the engaged position blocks the hydraulic shuttle element from attaining the first closed position; and
a second blocking element arranged to be moveable to an engaged position by the radial motion of the cylinder member whenever the blocking device is deployed with the cylinder member in the first position, wherein the engaged position blocks the hydraulic shuttle element from attaining the second closed position.

### Claim 5 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the hydraulic shuttle element is arranged to move by rotational motion around a central rotational axis of the valve body in response to pressure differences between the first chamber and the second chamber.

### Claim 6 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the hydraulic shuttle element comprises two or more hollows arranged to receive the at least one blocking element when engaged.

### Claim 7 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the at least one blocking element is deployed by increased external hydraulic pressure, by increased external pneumatic pressure, or by energization of a solenoid.

### Claim 8 (depends on 7)

A variable cam timing phaser arrangement according to claim 7, wherein the at least one blocking element is deployed by increased external hydraulic pressure and the external hydraulic pressure is regulated by a solenoid-controlled actuator located remotely from any rotating components of the cam timing phaser arrangement.

### Claim 9 (depends on 8)

A variable cam timing phaser arrangement according claim 8, wherein the solenoid-controlled actuator is a 3/2 way on/off solenoid valve having an inlet port in fluid communication with a source of increased fluid pressure an outlet port in fluid communication with the blocking device, and a vent port, wherein the primary state of the solenoid valve is a de-energized state preventing fluid communication from the source of increased fluid pressure to blocking device and allowing fluid communication from the blocking device to the vent port, and wherein the secondary state of the solenoid valve is an energized state allowing fluid communication from the source of increased fluid pressure to the blocking device and deploying the at least one blocking element.

### Claim 10 (depends on 8)

A variable cam timing phaser arrangement according to claim 8, wherein the solenoid-controlled actuator comprises a solenoid-driven plunger arranged in a barrel, the barrel being arranged in fluid communication with the blocking device, wherein the primary state of the solenoid-driven plunger is a retracted de-energized state and the secondary state of the solenoid-driven plunger is an extended energized state, the extended state increasing the pressure of the fluid at the blocking device and deploying the at least one blocking element.

### Claim 11 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein a source of increased fluid pressure is arranged in fluid communication with the first chamber and/or the second chamber via a refill channel.

### Claim 12 (depends on 1)

A variable cam timing phaser arrangement according to claim 1, wherein the hydraulic fluid is hydraulic oil.

### Claim 13

A method for controlling the timing of a camshaft in an internal combustion engine comprising a variable cam timing phaser arrangement comprising
a rotor having at least one vane, the rotor arranged to be connected to a camshaft;
a stator co-axially surrounding the rotor, having at least one recess for receiving the at least one vane of the rotor and allowing rotational movement of the rotor with respect to the stator, the stator having an outer circumference arranged for accepting drive force;
wherein the at least one vane divides the at least one recess into a first chamber and a second chamber, the first chamber and the second chamber being arranged to receive hydraulic fluid under pressure, wherein the introduction of hydraulic fluid into the first chamber causes the rotor to move in a first rotational direction relative to the stator and the introduction of hydraulic fluid into the second chamber causes the rotor to move in a second rotational direction relative to the stator, the second rotational direction being opposite the first rotational direction; and
a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa, wherein the control assembly comprises:
a cam torque actuation control valve located centrally within the rotor and/or camshaft, the CTA control valve comprising a valve body having a first port arranged in fluid communication with the first chamber, a second port arranged in fluid communication with the second chamber, and a hydraulic shuttle element arranged in the valve body; and
a blocking device arranged in conjunction with the valve body;
wherein the hydraulic shuttle element is configured to be moved in a first direction to a first closed position by overpressure in the first chamber and moved in the second direction to a second closed position by overpressure in the second chamber;
whereby in the first closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the first chamber to the second chamber; and
whereby in the second closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the second chamber to the first chamber; and
wherein the blocking device comprises at least one blocking element that is deployable between a disengaged position and an engaged position, wherein the at least one blocking element is in the engaged position configured to prevent the hydraulic shuttle element from moving to the first closed position or the second closed position depending on the position of the hydraulic shuttle element when the blocking device is deployed, whereby the hydraulic shuttle element is configured to move either between the first closed position in response to overpressure in the first chamber and a second open position in response to overpressure in the second chamber, or between the second closed position in response to overpressure in the second chamber and a first open position in response to overpressure in the first chamber;
whereby in the second open position the hydraulic shuttle element allows fluid flow from the second chamber to the first chamber; and
whereby in the first open position the hydraulic shuttle element allows fluid flow from the first chamber to the second chamber,
the method comprising the steps:
i. providing the variable cam timing phaser arrangement having the blocking device in a disengaged position, thereby preventing fluid communication between the first chamber and the second chamber;
ii. deploying the blocking device at a time to coincide with the hydraulic shuttle element being in the first position thereby engaging the at least one blocking element to block the second position; or deploying the blocking device at a time to coincide with the hydraulic shuttle element being in the second position thereby engaging the at least one blocking element to block the first position;
iii. maintaining the deployment of the blocking device thereby allowing fluid to periodically flow in a single direction between the first chamber and the second chamber due to camshaft torque, and preventing fluid flow in the opposite direction, thus rotating the rotor relative to the stator in a chosen direction; and
iv. once the desired rotation of the rotor relative to the stator is obtained, disengaging the blocking device, thereby preventing further fluid communication between the first chamber and the second chamber.

### Claim 14

An internal combustion engine comprising a variable cam timing phaser arrangement comprising
a rotor having at least one vane, the rotor arranged to be connected to a camshaft;
a stator co-axially surrounding the rotor, having at least one recess for receiving the at least one vane of the rotor and allowing rotational movement of the rotor with respect to the stator, the stator having an outer circumference arranged for accepting drive force;
wherein the at least one vane divides the at least one recess into a first chamber and a second chamber, the first chamber and the second chamber being arranged to receive hydraulic fluid under pressure, wherein the introduction of hydraulic fluid into the first chamber causes the rotor to move in a first rotational direction relative to the stator and the introduction of hydraulic fluid into the second chamber causes the rotor to move in a second rotational direction relative to the stator, the second rotational direction being opposite the first rotational direction; and
a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa, wherein the control assembly comprises:
a cam torque actuation control valve located centrally within the rotor and/or camshaft, the CTA control valve comprising a valve body having a first port arranged in fluid communication with the first chamber, a second port arranged in fluid communication with the second chamber, and a hydraulic shuttle element arranged in the valve body; and
a blocking device arranged in conjunction with the valve body;
wherein the hydraulic shuttle element is configured to be moved in a first direction to a first closed position by overpressure in the first chamber and moved in the second direction to a second closed position by overpressure in the second chamber;
whereby in the first closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the first chamber to the second chamber; and
whereby in the second closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the second chamber to the first chamber; and
wherein the blocking device comprises at least one blocking element that is deployable between a disengaged position and an engaged position, wherein the at least one blocking element is in the engaged position configured to prevent the hydraulic shuttle element from moving to the first closed position or the second closed position depending on the position of the hydraulic shuttle element when the blocking device is deployed, whereby the hydraulic shuttle element is configured to move either between the first closed position in response to overpressure in the first chamber and a second open position in response to overpressure in the second chamber, or between the second closed position in response to overpressure in the second chamber and a first open position in response to overpressure in the first chamber;
whereby in the second open position the hydraulic shuttle element allows fluid flow from the second chamber to the first chamber; and
whereby in the first open position the hydraulic shuttle element allows fluid flow from the first chamber to the second chamber.

### Claim 15

A vehicle comprising a variable cam timing phaser arrangement comprising
a rotor having at least one vane, the rotor arranged to be connected to a camshaft;
a stator co-axially surrounding the rotor, having at least one recess for receiving the at least one vane of the rotor and allowing rotational movement of the rotor with respect to the stator, the stator having an outer circumference arranged for accepting drive force;
wherein the at least one vane divides the at least one recess into a first chamber and a second chamber, the first chamber and the second chamber being arranged to receive hydraulic fluid under pressure, wherein the introduction of hydraulic fluid into the first chamber causes the rotor to move in a first rotational direction relative to the stator and the introduction of hydraulic fluid into the second chamber causes the rotor to move in a second rotational direction relative to the stator, the second rotational direction being opposite the first rotational direction; and
a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa, wherein the control assembly comprises:
a cam torque actuation control valve located centrally within the rotor and/or camshaft, the CTA control valve comprising a valve body having a first port arranged in fluid communication with the first chamber, a second port arranged in fluid communication with the second chamber, and a hydraulic shuttle element arranged in the valve body; and
a blocking device arranged in conjunction with the valve body;
wherein the hydraulic shuttle element is configured to be moved in a first direction to a first closed position by overpressure in the first chamber and moved in the second direction to a second closed position by overpressure in the second chamber;
whereby in the first closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the first chamber to the second chamber; and
whereby in the second closed position the hydraulic shuttle element forms a seal together with an inner wall of the valve body or a valve seat located in the valve body, thereby preventing fluid flow from the second chamber to the first chamber; and
wherein the blocking device comprises at least one blocking element that is deployable between a disengaged position and an engaged position, wherein the at least one blocking element is in the engaged position configured to prevent the hydraulic shuttle element from moving to the first closed position or the second closed position depending on the position of the hydraulic shuttle element when the blocking device is deployed, whereby the hydraulic shuttle element is configured to move either between the first closed position in response to overpressure in the first chamber and a second open position in response to overpressure in the second chamber, or between the second closed position in response to overpressure in the second chamber and a first open position in response to overpressure in the first chamber;
whereby in the second open position the hydraulic shuttle element allows fluid flow from the second chamber to the first chamber; and
whereby in the first open position the hydraulic shuttle element allows fluid flow from the first chamber to the second chamber.